ifcgeom: retry failed batched opening cuts sequentially (#487 )

convert_openings groups openings with similar minimal edge lengths into a single multi-tool BOPAlgo_CUT (batching introduced in 7c1071f588 for robustness and speed on the common case). On the file attached to #487 one such batch of 3 openings fails the interference checks at every fuzziness the retry ladder is allowed to attempt, because the ladder rightly refuses to raise fuzziness past the smallest real edge length of the 20mm recess operand, and the whole batch is dropped, leaving the wall uncut. Each of those openings subtracts cleanly when cut on its own. This adds a gated last resort in boolean_operation: only after a multi-tool CUT has exhausted every fuzziness attempt, reattempt it by applying the same tool operands one at a time, each cut feeding the next. The batched path stays the default; single-tool cuts and non-CUT operations are unaffected, and the fallback is all-or-nothing so a partial sequential success never silently replaces the operand. This change was written with the assistance of an AI coding tool.
2026-08-22 21:08:36 +00:00 · 2026-07-25 08:34:52 +03:00
94 changed files with 366 additions and 3446 deletions
@@ -20,7 +20,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7 # https://github.com/actions/checkout
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -66,7 +66,7 @@ jobs:
              short_name: macos
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
          python-version: '3.11'
@@ -49,7 +49,7 @@ jobs:
              short_name: macos
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
          python-version: '3.11'
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -38,7 +38,7 @@ jobs:
          }
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7
+      - uses: actions/setup-python@v6
        with:
          python-version: '3.11'
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7
+      - uses: actions/setup-python@v6
        with:
          python-version: '3.11'
      - name: Compile
@@ -50,7 +50,7 @@ jobs:
      - uses: actions/checkout@v7
        with:
          submodules: recursive
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -41,7 +41,7 @@ jobs:
      - uses: actions/checkout@v7
        with:
          submodules: recursive
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7
+      - uses: actions/setup-python@v6
        with:
          python-version: '3.11'
      - name: Compile
@@ -26,7 +26,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
          python-version: '3.11'
@@ -20,7 +20,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified
          python-version: '3.11'
@@ -19,7 +19,7 @@ jobs:
      fail-fast: false
    steps:
      - uses: actions/checkout@v7
-      - uses: actions/setup-python@v7 # https://github.com/actions/setup-python
+      - uses: actions/setup-python@v6 # https://github.com/actions/setup-python
        with:
          python-version: '3.11' # Version range or exact version of a Python version to use, using SemVer's version range syntax
      - name: Compile
@@ -85,7 +85,7 @@ jobs:
          cmake --build build-ifcopenshell --target install -j "$(nproc)"

      - name: Set up Python 3.11
-        uses: actions/setup-python@v7
+        uses: actions/setup-python@v6
        with:
          python-version: 3.11

@@ -120,7 +120,7 @@ jobs:
          PY

      - name: Set up Python 3.12
-        uses: actions/setup-python@v7
+        uses: actions/setup-python@v6
        with:
          python-version: 3.12

@@ -15,12 +15,12 @@ jobs:
        uses: actions/checkout@v7

      - name: Action - install python
-        uses: actions/setup-python@v7
+        uses: actions/setup-python@v6
        with:
          python-version: ${{ env.MIN_IOS_PY_VERSION }}

      - name: Action - install python
-        uses: actions/setup-python@v7
+        uses: actions/setup-python@v6
        with:
          python-version: ${{ env.MIN_BLENDER_PY_VERSION }}

@@ -48,7 +48,7 @@ jobs:
            submodules: recursive

      - name: Set up Python
-        uses: actions/setup-python@v7
+        uses: actions/setup-python@v6
        with:
          python-version: 3.11

@@ -263,9 +263,7 @@ jobs:
          cd ../ifcquery && make test || ERROR=1
          pip install -e ../ifcedit --no-deps
          cd ../ifcedit && make test || ERROR=1
-          # Pinned <2: mcp 2.0.0 renamed mcp.server.fastmcp.FastMCP to
-          # mcp.server.mcpserver.MCPServer, which ifcmcp doesn't support yet.
-          pip install "mcp>=1.0,<2"
+          pip install mcp
          pip install -e ../ifcmcp --no-deps
          cd ../ifcmcp && make test || ERROR=1
          pip install -e ../ifctester --no-deps
@@ -14,7 +14,7 @@ jobs:
        uses: actions/checkout@v7

      - name: Set up Python
-        uses: actions/setup-python@v7
+        uses: actions/setup-python@v6
        with:
          python-version: '3.x'

@@ -42,7 +42,7 @@ jobs:
        run: |
          rsync -av --delete --exclude='.git/' src/ifcchat/ output/
      - name: Setup Python
-        uses: actions/setup-python@v7
+        uses: actions/setup-python@v6
        with:
          python-version: "3.x"
      - name: Download wheels
@@ -236,8 +236,11 @@ def import_attribute(
    elif data_type == "integer":
        new.int_value = 0 if new.is_null else int(data[attribute.name()])
    elif data_type == "float":
-        measure_class = attribute.type_of_attribute().declared_type().name()
-        new.special_type = tool.Pset.get_special_type_for_measure_class(measure_class)
+        attribute_type = attribute.type_of_attribute()
+        if attribute_type._is("IfcLengthMeasure"):
+            new.special_type = "LENGTH"
+        elif attribute_type._is("IfcForceMeasure"):
+            new.special_type = "FORCE"
        new.float_value = 0.0 if new.is_null else float(data[attribute.name()])
    elif data_type == "enum":
        attribute_type = attribute.type_of_attribute()
@@ -54,7 +54,7 @@ class Data:
        ifc_file = tool.Ifc.get()
        results = []
        psetqtos = ifcopenshell.util.element.get_psets(
-            element, psets_only=psets_only, qtos_only=qtos_only, should_inherit=False, verbose=True
+            element, psets_only=psets_only, qtos_only=qtos_only, should_inherit=False
        )
        for name, data in sorted(psetqtos.items()):
            pset = ifc_file.by_id(data["id"])
@@ -69,28 +69,13 @@ class Data:
                    "id": data["id"],
                    "Name": name,
                    "is_expanded": is_expanded.get(data["id"], True),
-                    "Properties": [
-                        cls.property_display_data(ifc_file, k, v) for k, v in sorted(data.items()) if k != "id"
-                    ],
+                    "Properties": [{"Name": k, "NominalValue": v} for k, v in sorted(data.items()) if k != "id"],
                    "shared_pset_uses": len(pset_uses),
                    "has_template": has_template,
                }
            )
        return sorted(results, key=lambda v: v["Name"])

-    @classmethod
-    def property_display_data(cls, ifc_file: ifcopenshell.file, name: str, verbose_value: Any) -> dict[str, Any]:
-        # Predefined property sets (e.g. IfcDoorPanelProperties) expose plain
-        # attribute values even in verbose mode, since they're typed IFC
-        # attributes rather than IfcProperty entities with their own id/Unit.
-        if not isinstance(verbose_value, dict):
-            return {"Name": name, "NominalValue": verbose_value, "UnitSymbol": ""}
-
-        unit_symbol = ""
-        if (prop_id := verbose_value.get("id")) and (prop_entity := ifc_file.by_id(prop_id)):
-            unit_symbol = tool.Pset.get_unit_symbol_for_prop(prop_entity, ifc_file)
-        return {"Name": name, "NominalValue": verbose_value["value"], "UnitSymbol": unit_symbol}
-
    @classmethod
    def format_pset_enum(cls, psets):
        enum_items = []
@@ -120,20 +120,13 @@ class EditPset(bpy.types.Operator, tool.Ifc.Operator):
            properties = json.loads(self.properties)
        else:
            for prop in props.properties:
-                metadata = prop.metadata
                if prop.value_type == "IfcPropertySingleValue":
-                    value = metadata.get_value()
+                    properties[prop.metadata.name] = prop.metadata.get_value()
                elif prop.value_type == "IfcPropertyEnumeratedValue":
-                    value_name = metadata.get_value_name()
-                    value = [e[value_name] for e in prop.enumerated_value.enumerated_values if e.is_selected]
-                else:
-                    continue
-                # None (a purge/skip-creation signal, handled by edit_pset/edit_qto before any
-                # unit wrapping is unpacked) must stay bare -- only wrap real values.
-                if value is not None and tool.Pset.is_measurable_special_type(metadata.special_type):
-                    unit = self.file.by_id(metadata.unit_id) if metadata.unit_id else None
-                    value = {"NominalValue": value, "Unit": unit}
-                properties[metadata.name] = value
+                    value_name = prop.metadata.get_value_name()
+                    properties[prop.metadata.name] = [
+                        e[value_name] for e in prop.enumerated_value.enumerated_values if e.is_selected
+                    ]

        if pset.is_a() in ("IfcPropertySet", "IfcMaterialProperties", "IfcProfileProperties"):
            ifcopenshell.api.pset.edit_pset(
@@ -147,18 +140,10 @@ class EditPset(bpy.types.Operator, tool.Ifc.Operator):
            for key, value in properties.items():
                if value is None:
                    continue
-                is_wrapped = isinstance(value, dict) and "Unit" in value
-                raw = value["NominalValue"] if is_wrapped else value
-                if raw is None:
-                    continue
-                if isinstance(raw, float):
-                    raw = round(raw, 4)
-                elif not isinstance(raw, int):
-                    raw = 0
-                if is_wrapped:
-                    value["NominalValue"] = raw
-                else:
-                    properties[key] = raw
+                if isinstance(value, float):
+                    properties[key] = round(value, 4)
+                elif not isinstance(value, int):
+                    properties[key] = 0
            ifcopenshell.api.pset.edit_qto(
                self.file,
                qto=pset,
@@ -67,10 +67,6 @@ def draw_single_property(prop: IfcProperty, layout: bpy.types.UILayout, copy_ope
    if prop.metadata.special_type == "URI":
        op = layout.operator("bim.select_uri_attribute", text="", icon="FILE_FOLDER")
        op.attribute_data_path = tool.Blender.get_full_data_path(prop.metadata)
-    if tool.Pset.is_measurable_special_type(prop.metadata.special_type):
-        unit_row = layout.row(align=True)
-        unit_row.scale_x = 0.5
-        prop_with_search(unit_row, prop.metadata, "unit_id_enum", text="")
    if prop.metadata.is_optional:
        layout.prop(prop.metadata, "is_null", icon="RADIOBUT_OFF" if prop.metadata.is_null else "RADIOBUT_ON", text="")
    if copy_operator:
@@ -207,10 +203,9 @@ def draw_psetqto_ui(
                row = box.row(align=True)
                row.scale_y = 0.8
                row.label(text=prop["Name"])
-                display_value = get_display_value(nominal_value)
-                if unit_symbol := prop["UnitSymbol"]:
-                    display_value = f"{display_value} {unit_symbol}"
-                op = row.operator("bim.select_similar", text=display_value, icon="NONE", emboss=False)
+                op = row.operator(
+                    "bim.select_similar", text=get_display_value(nominal_value), icon="NONE", emboss=False
+                )
                op.key = '"' + pset["Name"].replace('"', '\\"') + '"."' + prop["Name"].replace('"', '\\"') + '"'
                # calculate sum of all selected objects
                if active_operator:
@@ -151,7 +151,7 @@ class CalculateSingleQuantity(bpy.types.Operator, tool.Ifc.Operator):
        ifc_file = tool.Ifc.get()
        with Profiler("Quantify function time:"):
            results = ifc5d.qto.quantify(ifc_file, elements, rules)
-        ifc5d.qto.edit_qtos(ifc_file, results, target_units=tool.Qto.get_target_units(), rules=rules)
+        ifc5d.qto.edit_qtos(ifc_file, results)

        not_quantified_elements = elements - set(results.keys())
        not_quantified_message = tool.Qto.get_not_quantified_elements_message(not_quantified_elements)
@@ -194,7 +194,7 @@ class PerformQuantityTakeOff(bpy.types.Operator, tool.Ifc.Operator):
            ifc_file = tool.Ifc.get()
            with Profiler("Quantify function time:"):
                results = ifc5d.qto.quantify(ifc_file, elements, rules)
-            ifc5d.qto.edit_qtos(ifc_file, results, target_units=tool.Qto.get_target_units(), rules=rules)
+            ifc5d.qto.edit_qtos(ifc_file, results)
            not_quantified_elements = elements - set(results.keys())
            return not_quantified_elements

@@ -27,28 +27,10 @@ from bpy.props import (
 )
 from bpy.types import PropertyGroup

-import bonsai.bim.prop
 import bonsai.tool as tool

 CALCULATOR_FUNCTION_ENUM_ITEMS: list[Union[tuple[str, str, str], None]] = []

-# Measure class (matching ifc5d.qto's Function.measure / SI2ProjectUnitConverter.project_units'
-# keys) -> (BIMQtoProperties field name, tool.Pset special_type, UI label).
-MEASURE_TO_TARGET_UNIT_FIELD: dict[str, tuple[str, str, str]] = {
-    "IfcLengthMeasure": ("target_unit_length", "LENGTH", "Length"),
-    "IfcAreaMeasure": ("target_unit_area", "AREA", "Area"),
-    "IfcVolumeMeasure": ("target_unit_volume", "VOLUME", "Volume"),
-    "IfcMassMeasure": ("target_unit_mass", "MASS", "Mass"),
-    "IfcTimeMeasure": ("target_unit_time", "TIME", "Time"),
-}
-
-
-def _target_unit_items(special_type: str):
-    def getter(self: "BIMQtoProperties", context: bpy.types.Context) -> tool.Blender.BLENDER_ENUM_ITEMS:
-        return bonsai.bim.prop.get_unit_enum_items_for_special_type(special_type, tool.Ifc.get())
-
-    return getter
-

 def get_qto_rule(self: "BIMQtoProperties", context: bpy.types.Context) -> list[tuple[str, str, str]]:
    results: list[tuple[str, str, str]] = []
@@ -110,11 +92,6 @@ class BIMQtoProperties(PropertyGroup):
        ),
        default=False,
    )
-    target_unit_length: EnumProperty(items=_target_unit_items("LENGTH"), name="Length Unit")
-    target_unit_area: EnumProperty(items=_target_unit_items("AREA"), name="Area Unit")
-    target_unit_volume: EnumProperty(items=_target_unit_items("VOLUME"), name="Volume Unit")
-    target_unit_mass: EnumProperty(items=_target_unit_items("MASS"), name="Mass Unit")
-    target_unit_time: EnumProperty(items=_target_unit_items("TIME"), name="Time Unit")

    if TYPE_CHECKING:
        qto_rule: str
@@ -124,8 +101,3 @@ class BIMQtoProperties(PropertyGroup):
        qto_name: str
        prop_name: str
        fallback: bool
-        target_unit_length: str
-        target_unit_area: str
-        target_unit_volume: str
-        target_unit_mass: str
-        target_unit_time: str
@@ -17,12 +17,9 @@
 # along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.

 import bpy
-import ifc5d.qto

 import bonsai.tool as tool
-from bonsai.bim.helper import prop_with_search
 from bonsai.bim.module.qto.data import QtoData
-from bonsai.bim.module.qto.prop import MEASURE_TO_TARGET_UNIT_FIELD


 class BIM_PT_qto(bpy.types.Panel):
@@ -47,14 +44,6 @@ class BIM_PT_qto(bpy.types.Panel):
        row = layout.row()
        row.prop(props, "qto_rule", text="")
        row.prop(props, "fallback", text="", icon="RADIOBUT_ON" if props.fallback else "RADIOBUT_OFF")
-
-        box = layout.box()
-        box.label(text="Target Units (optional, otherwise project default)")
-        for field_name, _special_type, label in MEASURE_TO_TARGET_UNIT_FIELD.values():
-            row = box.row(align=True)
-            row.label(text=label)
-            prop_with_search(row, props, field_name, text="")
-
        row = layout.row()
        row.operator("bim.perform_quantity_take_off")

@@ -77,15 +66,6 @@ class BIM_PT_qto_manual(bpy.types.Panel):
        row = layout.row()
        row.prop(props, "calculator_function", text="Function")

-        calculator = ifc5d.qto.calculators.get(props.calculator)
-        function = calculator.functions.get(props.calculator_function) if calculator else None
-        target_unit_field = MEASURE_TO_TARGET_UNIT_FIELD.get(function.measure) if function else None
-        if target_unit_field:
-            field_name, _special_type, label = target_unit_field
-            row = layout.row(align=True)
-            row.label(text=f"{label} Unit")
-            prop_with_search(row, props, field_name, text="")
-
        row = layout.row(align=True)
        row.prop(props, "qto_name", text="")
        row.prop(props, "prop_name", text="")
@@ -21,6 +21,7 @@ import os
 from typing import TYPE_CHECKING, Any, Literal, Union, assert_never, get_args

 import bpy
+import ifcopenshell.util.unit
 from bpy.props import (
    BoolProperty,
    CollectionProperty,
@@ -33,8 +34,6 @@ from bpy.props import (
 )
 from bpy.types import PropertyGroup

-import ifcopenshell.util.unit
-
 import bonsai.bim
 import bonsai.bim.handler
 import bonsai.tool as tool
@@ -123,57 +122,6 @@ def get_attribute_enum_values(prop: "Attribute", context: bpy.types.Context) ->
    return items


-def get_unit_enum_items_for_special_type(
-    special_type: str, ifc_file: Union[ifcopenshell.file, None]
-) -> tool.Blender.BLENDER_ENUM_ITEMS:
-    """Items for a unit-override picker: "Default (<symbol>)" plus every candidate unit
-    matching `special_type`, filtered per-caller since candidates depend on the measure type
-    in question (unlike the globally-shared lists in `bonsai.bim.ui.EnumData`).
-    """
-    if not ifc_file or not tool.Pset.is_measurable_special_type(special_type):
-        return [(cache_string("0"), cache_string("Default"), "")]
-
-    default_symbol = tool.Pset.get_unit_symbol_for_special_type(special_type, ifc_file)
-    items: list[tuple[str, str, str]] = [
-        (cache_string("0"), cache_string(f"Default ({default_symbol})" if default_symbol else "Default"), "")
-    ]
-    for unit in tool.Pset.get_candidate_units_for_special_type(special_type, ifc_file):
-        name = getattr(unit, "Name", None) or unit.is_a()
-        symbol = ifcopenshell.util.unit.get_unit_symbol(unit)
-        label = f"{name} ({symbol})" if symbol else name
-        items.append((cache_string(str(unit.id())), cache_string(label), ""))
-    return items
-
-
-def get_attribute_unit_enum_items(prop: "Attribute", context: bpy.types.Context) -> tool.Blender.BLENDER_ENUM_ITEMS:
-    """Items for `Attribute.unit_id_enum`. Wraps `get_unit_enum_items_for_special_type` with a
-    defensive addition: real-world files sometimes carry a Unit that doesn't cleanly match our
-    candidate-matching logic (e.g. a mismatched UnitType). Always keep the attribute's own
-    current override selectable/representable, however unusual, so setting unit_id_enum to
-    match an already-seeded unit_id can never raise "enum not found".
-    """
-    ifc_file = tool.Ifc.get()
-    items = get_unit_enum_items_for_special_type(prop.special_type, ifc_file)
-
-    if prop.unit_id and prop.unit_id not in {int(i[0]) for i in items}:
-        own_unit = ifc_file.by_id(prop.unit_id)
-        name = getattr(own_unit, "Name", None) or own_unit.is_a()
-        symbol = ifcopenshell.util.unit.get_unit_symbol(own_unit)
-        label = f"{name} ({symbol})" if symbol else name
-        items.append((cache_string(str(prop.unit_id)), cache_string(label), ""))
-
-    return items
-
-
-def update_attribute_unit_id(self: "Attribute", context: bpy.types.Context) -> None:
-    new_unit_id = int(tool.Blender.get_enum_safe(self, "unit_id_enum") or "0")
-    if ifc_file := tool.Ifc.get():
-        # Must run before self.unit_id is overwritten: convert_attribute_unit needs the OLD
-        # unit_id to know what unit the current value is expressed in.
-        tool.Pset.convert_attribute_unit(self, new_unit_id, ifc_file)
-    self.unit_id = new_unit_id
-
-
 def update_schema_dir(self: "BIMProperties", context: bpy.types.Context) -> None:
    import bonsai.bim.schema

@@ -302,33 +250,44 @@ def set_numerical_value(self: "Attribute", value_name: str, new_value: Union[flo
    self[value_name] = new_value


+def get_length_value(self: "Attribute") -> float:
+    si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
+    return self.float_value * si_conversion
+
+
+def set_length_value(self: "Attribute", value: float) -> None:
+    si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
+    self.float_value = value / si_conversion
+
+
 def get_display_name(self: "Attribute") -> str:
+    DISPLAY_UNIT_TYPES = ("AREA", "VOLUME", "FORCE")
    name = self.name
-    if not self.unit_symbol:
+    if not self.special_type or self.special_type not in DISPLAY_UNIT_TYPES:
        return name
-    return f"{name}, {self.unit_symbol}"

+    unit_type = f"{self.special_type}UNIT"
+    project_unit = ifcopenshell.util.unit.get_project_unit(tool.Ifc.get(), unit_type)
+    if not project_unit:
+        return name

-def get_unit_symbol(self: "Attribute") -> str:
-    """The symbol for whatever unit the value is currently expressed in: this property's own
-    override (`unit_id`) if set, else the project default for `special_type`. Computed fresh on
-    every access (rather than cached at import time) so it stays correct immediately after the
-    unit picker changes `unit_id`, and after the project's own default units are edited.
-    """
-    if not tool.Pset.is_measurable_special_type(self.special_type):
-        return ""
-    if not (ifc_file := tool.Ifc.get()):
-        return ""
-    unit = tool.Pset.resolve_effective_unit(self.special_type, self.unit_id, ifc_file)
-    return ifcopenshell.util.unit.get_unit_symbol(unit) if unit else ""
+    unit_symbol = ifcopenshell.util.unit.get_unit_symbol(project_unit)
+    return f"{name}, {unit_symbol}"


 AttributeDataType = Literal["string", "integer", "float", "boolean", "enum", "file", "list[string]"]
-# Either "", "DATE", "DATETIME", "LOGICAL", "URI", "DURATION", or an
-# IfcUnitEnum/IfcDerivedUnitEnum value with the "UNIT" suffix stripped (e.g.
-# "LENGTH", "PRESSURE", "MODULUSOFELASTICITY") as returned by
-# tool.Pset.get_special_type_for_prop().
-AttributeSpecialType = str
+AttributeSpecialType = Literal[
+    "",
+    "DATE",
+    "DATETIME",
+    "LENGTH",
+    "AREA",
+    "VOLUME",
+    "FORCE",
+    "LOGICAL",
+    "URI",
+    "DURATION",
+]


 class Attribute(PropertyGroup):
@@ -359,6 +318,9 @@ class Attribute(PropertyGroup):
        get=lambda self: float(self.get("float_value", 0.0)),
        set=set_float_value,
    )
+    length_value: FloatProperty(
+        name="Value", description=tooltip, get=get_length_value, set=set_length_value, unit="LENGTH"
+    )
    enum_items: StringProperty(name="Value")
    """Json serialized mapping of enum items:
        Typically a dictionary of string identifiers to item names.
@@ -380,10 +342,6 @@ class Attribute(PropertyGroup):
    value_max: FloatProperty(description="This is used to validate int_value and float_value")
    value_max_constraint: BoolProperty(default=False, description="True if the numerical value has an upper bound")
    special_type: StringProperty(name="Special Value Type", default="")
-    unit_symbol: StringProperty(name="Unit Symbol", get=get_unit_symbol)
-    unit_id: IntProperty(name="Unit Override", default=0)
-    """STEP id of this property/quantity's own Unit override. 0 means "use the project default"."""
-    unit_id_enum: EnumProperty(items=get_attribute_unit_enum_items, name="Unit", update=update_attribute_unit_id)
    use_explorer_ui: BoolProperty()
    metadata: StringProperty(name="Metadata", description="For storing some additional information about the attribute")
    update: StringProperty(name="Update", description="Custom update function to be executed")
@@ -399,6 +357,7 @@ class Attribute(PropertyGroup):
        bool_value: bool
        int_value: int
        float_value: float
+        length_value: float
        enum_items: str
        enum_items_dynamic: str
        enum_descriptions: bpy.types.bpy_prop_collection_idprop[StrProperty]
@@ -414,9 +373,6 @@ class Attribute(PropertyGroup):
        value_min_constraint: bool
        value_max: float
        value_max_constraint: bool
-        unit_symbol: str
-        unit_id: int
-        unit_id_enum: str
        use_explorer_ui: bool
        metadata: str
        update: str
@@ -474,6 +430,8 @@ class Attribute(PropertyGroup):
        elif data_type == "integer":
            return "int_value"
        elif data_type == "float":
+            if display_only and self.special_type == "LENGTH":
+                return "length_value"
            return "float_value"
        elif data_type == "enum":
            return "enum_value"
@@ -222,6 +222,7 @@ def generate_space(

    if element and element.is_a("IfcSpace"):
        spatial.set_space_representation_from_polygon(active_obj, element, space_polygon, h, polygon_is_si=True)
+        spatial.translate_obj_to_z_location(active_obj, z)
    else:
        if relating_type:
            name = model.generate_occurrence_name(relating_type, "IfcSpace")
@@ -26,7 +26,6 @@ import ifcopenshell
 import ifcopenshell.api.pset
 import ifcopenshell.util.attribute
 import ifcopenshell.util.element
-import ifcopenshell.util.unit

 import bonsai.bim.helper
 import bonsai.bim.schema
@@ -169,144 +168,42 @@ class Pset(bonsai.core.tool.Pset):
            pset_id=0, pset_name=cls.get_pset_name(obj, obj_type), pset_type="PSET", obj=obj, obj_type=obj_type
        )

-    # Templates for quantities can specify their kind via TemplateType (e.g.
-    # "Q_LENGTH") instead of PrimaryMeasureType. IfcQuantityCount has no
-    # associated measure/unit, so it is intentionally absent here.
-    QUANTITY_TEMPLATE_TYPE_TO_SPECIAL_TYPE = {
-        "Q_LENGTH": "LENGTH",
-        "Q_AREA": "AREA",
-        "Q_VOLUME": "VOLUME",
-        "Q_WEIGHT": "MASS",
-        "Q_TIME": "TIME",
-    }
-
    @classmethod
-    def get_special_type_for_measure_class(cls, measure_class: str) -> str:
-        """Get the ``special_type`` (an IfcUnitEnum value with "UNIT" stripped) for an IFC measure class.
-
-        :param measure_class: An IFC measure class name, e.g. "IfcLengthMeasure".
-        :return: E.g. "LENGTH", or "" if the class has no associated unit type.
-        """
-        if not measure_class.endswith("Measure"):
-            return ""
-        unit_type = ifcopenshell.util.unit.get_measure_unit_type(measure_class)
-        return unit_type[: -len("UNIT")] if unit_type.endswith("UNIT") else ""
-
-    @classmethod
-    def get_special_type_for_unit(cls, unit: ifcopenshell.entity_instance) -> str:
-        """Get the ``special_type`` (an IfcUnitEnum value with "UNIT" stripped) directly from
-        a Unit entity, for properties whose NominalValue is a generic numeric type (e.g.
-        IfcReal) rather than a proper measure class, but which still carry a real Unit.
-        """
-        unit_type = getattr(unit, "UnitType", None)
-        if unit_type and unit_type != "USERDEFINED":
-            return unit_type[: -len("UNIT")] if unit_type.endswith("UNIT") else ""
-        dimension_type = ifcopenshell.util.unit.identify_unit_dimensions(unit)
-        return dimension_type[: -len("UNIT")] if dimension_type else ""
-
-    @classmethod
-    def get_special_type_for_prop(cls, prop_or_prop_template: ifcopenshell.entity_instance) -> str:
-        """Classify a property/quantity/template by its measure type.
-
-        :return: An IfcUnitEnum value with the "UNIT" suffix stripped (e.g.
-            "LENGTH", "PRESSURE"), "URI" for IfcURIReference, or "" if the
-            value has no associated unit type.
-        """
+    def get_special_type_for_prop(
+        cls, prop_or_prop_template: ifcopenshell.entity_instance
+    ) -> Literal["LENGTH"] | Literal["AREA"] | Literal["VOLUME"] | Literal["URI"] | Literal[""]:
+        special_type = ""
        if prop_or_prop_template.is_a("IfcPropertyTemplate"):
            primary_measure_type = prop_or_prop_template.PrimaryMeasureType
-            if primary_measure_type == "IfcURIReference":
-                return "URI"
-            if primary_measure_type:
-                return cls.get_special_type_for_measure_class(primary_measure_type)
-            return cls.QUANTITY_TEMPLATE_TYPE_TO_SPECIAL_TYPE.get(prop_or_prop_template.TemplateType, "")
-        elif prop_or_prop_template.is_a("IfcPropertySingleValue"):
-            value = prop_or_prop_template.NominalValue
-            if value is not None:
-                special_type = cls.get_special_type_for_measure_class(value.is_a())
-                if special_type:
-                    return special_type
-                # Some property sets declare a generic numeric type (e.g. IfcReal) rather
-                # than a proper measure class, relying on an explicit Unit attribute alone to
-                # convey the dimension. Still measurable -- derive special_type from the Unit
-                # itself rather than (fruitlessly) from NominalValue's declared type.
-                if value.is_a() in ("IfcReal", "IfcInteger"):
-                    if unit := getattr(prop_or_prop_template, "Unit", None):
-                        return cls.get_special_type_for_unit(unit)
-        elif prop_or_prop_template.is_a("IfcPhysicalSimpleQuantity"):
-            entity = prop_or_prop_template.wrapped_data.declaration().as_entity()
-            measure_class = entity.attribute_by_index(3).type_of_attribute().declared_type().name()
-            return cls.get_special_type_for_measure_class(measure_class)
-        return ""
-
-    @classmethod
-    def get_unit_symbol_for_special_type(cls, special_type: str, ifc_file: ifcopenshell.file) -> str:
-        """Get the project's default unit symbol for a `special_type` (see `get_special_type_for_prop`).
-
-        Used where there's no property instance to check for a `Unit` override
-        (e.g. a template, or a native IFC entity attribute, neither of which
-        can carry one).
-        """
-        if not special_type or special_type == "URI":
-            return ""
-        unit = ifcopenshell.util.unit.get_project_unit(ifc_file, f"{special_type}UNIT")
-        return ifcopenshell.util.unit.get_unit_symbol(unit) if unit else ""
-
-    @classmethod
-    def get_unit_symbol_for_prop(cls, prop: ifcopenshell.entity_instance, ifc_file: ifcopenshell.file) -> str:
-        """Get the unit symbol for an existing property/quantity, respecting its own `Unit` override.
-
-        Gated on the property being classified as measurable (see `get_special_type_for_prop`,
-        which already accounts for a Unit attached to a generic numeric value) -- this only
-        excludes a Unit attached to a property whose value has no numeric/measure semantics at
-        all (e.g. text), where a stray Unit shouldn't be surfaced as a resolved unit.
-        """
-        if not cls.is_measurable_special_type(cls.get_special_type_for_prop(prop)):
-            return ""
-        unit = ifcopenshell.util.unit.get_property_unit(prop, ifc_file)
-        return ifcopenshell.util.unit.get_unit_symbol(unit) if unit else ""
-
-    # special_type values that don't denote a real unit-bearing measure (see get_special_type_for_prop).
-    NON_MEASURABLE_SPECIAL_TYPES = frozenset({"", "DATE", "DATETIME", "LOGICAL", "URI", "DURATION"})
-
-    @classmethod
-    def is_measurable_special_type(cls, special_type: str) -> bool:
-        """True if `special_type` (see `get_special_type_for_prop`) denotes a real unit-bearing measure."""
-        return special_type not in cls.NON_MEASURABLE_SPECIAL_TYPES
-
-    @classmethod
-    def get_candidate_units_for_special_type(
-        cls, special_type: str, ifc_file: ifcopenshell.file
-    ) -> list[ifcopenshell.entity_instance]:
-        """All units in the file usable as an override for a `special_type` (see `get_special_type_for_prop`)."""
-        if not cls.is_measurable_special_type(special_type):
-            return []
-        return ifcopenshell.util.unit.get_candidate_units(ifc_file, f"{special_type}UNIT")
-
-    @classmethod
-    def resolve_effective_unit(
-        cls, special_type: str, unit_id: int, ifc_file: ifcopenshell.file
-    ) -> Union[ifcopenshell.entity_instance, None]:
-        """The unit a value is currently expressed in: its own override (`unit_id`, a STEP id,
-        0 meaning "no override"), or the project default for `special_type` otherwise."""
-        if unit_id:
-            return ifc_file.by_id(unit_id)
-        return ifcopenshell.util.unit.get_project_unit(ifc_file, f"{special_type}UNIT")
-
-    @classmethod
-    def convert_attribute_unit(cls, metadata: "Attribute", new_unit_id: int, ifc_file: ifcopenshell.file) -> None:
-        """Rescale `metadata.float_value` in place so its physical quantity is preserved when
-        switching from its current effective unit to the unit named by `new_unit_id` (0 = project
-        default). No-op for non-measurable attributes or when old and new resolve to the same unit.
-        """
-        if not cls.is_measurable_special_type(metadata.special_type):
-            return
-        old_unit = cls.resolve_effective_unit(metadata.special_type, metadata.unit_id, ifc_file)
-        new_unit = cls.resolve_effective_unit(metadata.special_type, new_unit_id, ifc_file)
-        if old_unit is None or new_unit is None or old_unit == new_unit:
-            return
-        old_scale = ifcopenshell.util.unit.get_unit_scale(old_unit)
-        new_scale = ifcopenshell.util.unit.get_unit_scale(new_unit)
-        metadata.float_value = metadata.float_value * old_scale / new_scale
+            template_type = prop_or_prop_template.TemplateType
+            if primary_measure_type in ("IfcPositiveLengthMeasure", "IfcLengthMeasure") or template_type == "Q_LENGTH":
+                special_type = "LENGTH"
+            elif primary_measure_type == "IfcAreaMeasure" or template_type == "Q_AREA":
+                special_type = "AREA"
+            elif primary_measure_type == "IfcVolumeMeasure" or template_type == "Q_VOLUME":
+                special_type = "VOLUME"
+            elif primary_measure_type == "IfcURIReference":
+                special_type = "URI"
+        else:
+            if prop_or_prop_template.is_a("IfcPropertySingleValue"):
+                value = prop_or_prop_template.NominalValue
+                if value is not None:
+                    value_type = value.is_a()
+                    if value_type in ("IfcLengthMeasure", "IfcPositiveLengthMeasure"):
+                        special_type = "LENGTH"
+                    elif value_type == "IfcAreaMeasure":
+                        special_type = "AREA"
+                    elif value_type == "IfcVolumeMeasure":
+                        special_type = "VOLUME"
+            elif prop_or_prop_template.is_a("IfcPhysicalSimpleQuantity"):
+                prop_class = prop_or_prop_template.is_a()
+                if prop_class == "IfcQuantityArea":
+                    special_type = "AREA"
+                elif prop_class == "IfcQuantityVolume":
+                    special_type = "VOLUME"
+                elif prop_class == "IfcQuantityLength":
+                    special_type = "LENGTH"
+        return special_type

    @classmethod
    def import_pset_from_existing(
@@ -386,15 +283,6 @@ class Pset(bonsai.core.tool.Pset):
                metadata.is_null = value is None
                metadata.is_optional = True
                metadata.special_type = cls.get_special_type_for_prop(prop)
-                # The prop's OWN Unit override only -- metadata.unit_symbol is computed fresh from
-                # special_type/unit_id on every access (see Attribute.get_unit_symbol), so it
-                # already accounts for the project-default fallback once unit_id is set below.
-                # Some real-world files (e.g. certain exporters) set Unit on properties that
-                # aren't actually measures -- ignore it there, since we only ever treat Unit as
-                # meaningful for measurable special_types (matching the UI picker's own gating).
-                own_unit = getattr(prop, "Unit", None) if cls.is_measurable_special_type(metadata.special_type) else None
-                metadata.unit_id = own_unit.id() if own_unit else 0
-                metadata.unit_id_enum = str(metadata.unit_id)
                metadata.set_value(metadata.get_value_default() if metadata.is_null else value)
                process_prop_description(metadata)

@@ -521,8 +409,6 @@ class Pset(bonsai.core.tool.Pset):
                cls.import_single_value_from_template(pset_template, prop_template, simplified_data, props)

            elif prop_template.TemplateType.startswith("Q_"):
-                if prop_data:
-                    continue  # Existing quantity will be added later by import_pset_from_existing.
                cls.import_single_value_from_template(pset_template, prop_template, simplified_data, props)

            elif prop_template.TemplateType == "P_ENUMERATEDVALUE":
@@ -176,19 +176,6 @@ class Qto(bonsai.core.tool.Qto):
        is_ifc4x3 = ifc_file.schema == "IFC4X3"
        return {rule_id: rule for rule_id, rule in ifc5d.qto.rules.items() if rule_id.startswith("IFC4X3") == is_ifc4x3}

-    @classmethod
-    def get_target_units(cls) -> dict[str, ifcopenshell.entity_instance]:
-        from bonsai.bim.module.qto.prop import MEASURE_TO_TARGET_UNIT_FIELD
-
-        props = cls.get_qto_props()
-        ifc_file = tool.Ifc.get()
-        target_units: dict[str, ifcopenshell.entity_instance] = {}
-        for measure_class, (field_name, _special_type, _label) in MEASURE_TO_TARGET_UNIT_FIELD.items():
-            unit_id = int(tool.Blender.get_enum_safe(props, field_name) or "0")
-            if unit_id:
-                target_units[measure_class] = ifc_file.by_id(unit_id)
-        return target_units
-
    @classmethod
    def get_not_quantified_elements_message(cls, not_quantified_elements: set[ifcopenshell.entity_instance]) -> str:
        not_quantified_message = ""
@@ -361,22 +361,31 @@ Scenario: Edit pset length property
    Given an empty IFC project
    And I press "mesh.add_stair"
    And the variable "pset" is "tool.Pset.get_element_pset(tool.Ifc.get_entity(bpy.context.active_object), 'Pset_StairFlightCommon').id()"
+    And the variable "si_conversion" is "ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())"
    And I press "bim.enable_pset_editing(pset_id={pset}, obj='IfcStairFlight/StairFlight', obj_type='Object')"

    # Testing IfcPositiveLengthMeasure type of prop
    Then "active_object.PsetProperties.properties['TreadLength'].metadata.special_type" is "LENGTH"
    And "active_object.PsetProperties.properties['TreadLength'].metadata.float_value" is "250"
+    And "active_object.PsetProperties.properties['TreadLength'].metadata.length_value" is roughly "0.25"

    When I set "active_object.PsetProperties.properties['TreadLength'].metadata.float_value" to "350"
    Then "active_object.PsetProperties.properties['TreadLength'].metadata.float_value" is roughly "350"

+    When I set "active_object.PsetProperties.properties['TreadLength'].metadata.length_value" to "0.45"
+    Then "active_object.PsetProperties.properties['TreadLength'].metadata.float_value" is roughly "450"
+
    # Testing IfcLengthMeasure type of prop
    Then "active_object.PsetProperties.properties['NosingLength'].metadata.special_type" is "LENGTH"
    And "active_object.PsetProperties.properties['NosingLength'].metadata.float_value" is "0.0"
+    And "active_object.PsetProperties.properties['NosingLength'].metadata.length_value" is roughly "0.0"

    When I set "active_object.PsetProperties.properties['NosingLength'].metadata.float_value" to "350"
    Then "active_object.PsetProperties.properties['NosingLength'].metadata.float_value" is roughly "350"

+    When I set "active_object.PsetProperties.properties['NosingLength'].metadata.length_value" to "0.45"
+    Then "active_object.PsetProperties.properties['NosingLength'].metadata.float_value" is roughly "450"
+
    When I press "bim.edit_pset(obj='IfcStairFlight/StairFlight', obj_type='Object')"
    Then nothing happens

@@ -385,14 +394,19 @@ Scenario: Edit qset length property
    And I press "mesh.add_stair"
    And I press "bim.perform_quantity_take_off"
    And the variable "pset" is "tool.Pset.get_element_pset(tool.Ifc.get_entity(bpy.context.active_object), 'Qto_StairFlightBaseQuantities').id()"
+    And the variable "si_conversion" is "ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())"
    And I press "bim.enable_pset_editing(pset_id={pset}, obj='IfcStairFlight/StairFlight', obj_type='Object')"

    # Testing Q_LENGTH type of prop
    Then "active_object.PsetProperties.properties['Length'].metadata.special_type" is "LENGTH"
    And "active_object.PsetProperties.properties['Length'].metadata.float_value" is roughly "2156.485"
+    And "active_object.PsetProperties.properties['Length'].metadata.length_value" is roughly "2.156"

    When I set "active_object.PsetProperties.properties['Length'].metadata.float_value" to "350"
-    Then "active_object.PsetProperties.properties['Length'].metadata.float_value" is roughly "350"
+    Then "active_object.PsetProperties.properties['Length'].metadata.length_value" is roughly "0.35"
+
+    When I set "active_object.PsetProperties.properties['Length'].metadata.length_value" to "0.45"
+    Then "active_object.PsetProperties.properties['Length'].metadata.float_value" is roughly "450"

    When I press "bim.edit_pset(obj='IfcStairFlight/StairFlight', obj_type='Object')"
    Then nothing happens
@@ -1,328 +0,0 @@
-# Bonsai - OpenBIM Blender Add-on
-# Copyright (C) 2026
-#
-# This file is part of Bonsai.
-#
-# Bonsai is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# Bonsai is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with Bonsai.  If not, see <http://www.gnu.org/licenses/>.
-
-import bpy
-import ifcopenshell
-import ifcopenshell.api.pset
-import ifcopenshell.api.root
-import ifcopenshell.api.unit
-import pytest
-
-import bonsai.bim.prop
-import bonsai.tool as tool
-from test.bim.bootstrap import NewFile
-
-
-def import_single_property(ifc, element, prop):
-    """Import a single existing IfcProperty into a real, addon-registered
-    PsetProperties collection, exactly as the property editor does, and
-    return its `metadata` (an `Attribute`)."""
-    pset = ifcopenshell.api.pset.add_pset(ifc, product=element, name="Pset_Test")
-    pset.HasProperties = [prop]
-    obj = bpy.data.objects.new(prop.Name, None)
-    tool.Ifc.link(element, obj)
-    props = obj.PsetProperties
-    tool.Pset.import_pset_from_existing(pset, props, None)
-    return props.properties[prop.Name].metadata
-
-
-class TestGetDisplayName(NewFile):
-    def test_appends_the_resolved_unit_symbol(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        pressure = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="PRESSUREUNIT")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[pressure])
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcPressureMeasure(5.0))
-        metadata = import_single_property(ifc, element, prop)
-
-        assert metadata.display_name == "Foo, Pa"
-
-    def test_falls_back_to_the_plain_name_when_no_unit_is_resolvable(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        # No units assigned to the project at all -- nothing to resolve.
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcPressureMeasure(5.0))
-        metadata = import_single_property(ifc, element, prop)
-
-        assert metadata.unit_symbol == ""
-        assert metadata.display_name == "Foo"
-
-    def test_falls_back_to_the_plain_name_for_a_non_measure_property(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcText("Bar"))
-        metadata = import_single_property(ifc, element, prop)
-
-        assert metadata.unit_symbol == ""
-        assert metadata.display_name == "Foo"
-
-    def test_resolves_a_unit_explicitly_attached_to_a_generic_numeric_value(self):
-        # A generic IfcReal has no unit semantics per its own declared type, but a property
-        # set may still explicitly attach a real Unit to a specific instance to convey the
-        # dimension the spec's generic typing doesn't. That explicit Unit is real, deliberate
-        # data (not incidental/stray), so it should resolve normally.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcReal(150.0), Unit=length_mm)
-        metadata = import_single_property(ifc, element, prop)
-
-        assert metadata.unit_symbol == "mm"
-        assert metadata.display_name == "Foo, mm"
-
-
-class TestGetAttributeUnitEnumItems(NewFile):
-    def test_returns_default_plus_one_per_candidate_for_a_measurable_type(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcLengthMeasure(2.5))
-        metadata = import_single_property(ifc, element, prop)
-
-        items = bonsai.bim.prop.get_attribute_unit_enum_items(metadata, bpy.context)
-        identifiers = [i[0] for i in items]
-        assert identifiers[0] == "0"
-        assert str(length_mm.id()) in identifiers
-        assert str(length_m.id()) in identifiers
-        assert len(items) == 3  # Default + mm + m
-
-    def test_returns_just_default_for_non_measurable_types(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcText("Bar"))
-        metadata = import_single_property(ifc, element, prop)
-
-        items = bonsai.bim.prop.get_attribute_unit_enum_items(metadata, bpy.context)
-        assert [i[0] for i in items] == ["0"]
-
-
-class TestGetUnitEnumItemsForSpecialType(NewFile):
-    def test_matches_the_attribute_wrapper_output(self):
-        # Regression test for extracting get_unit_enum_items_for_special_type out of
-        # get_attribute_unit_enum_items: the wrapper must still produce identical items for
-        # the plain (no own-unit-fallback-needed) case.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcLengthMeasure(2.5))
-        metadata = import_single_property(ifc, element, prop)
-
-        direct_items = bonsai.bim.prop.get_unit_enum_items_for_special_type(metadata.special_type, ifc)
-        wrapper_items = bonsai.bim.prop.get_attribute_unit_enum_items(metadata, bpy.context)
-        assert direct_items == wrapper_items
-
-    def test_returns_just_default_when_ifc_file_is_none(self):
-        assert bonsai.bim.prop.get_unit_enum_items_for_special_type("LENGTH", None) == [("0", "Default", "")]
-
-
-class TestUnitSymbolWithAreaVolumeDerivedFromLength(NewFile):
-    """Regression test: AREAUNIT/VOLUMEUNIT have no IfcDerivedUnitEnum member, so a project
-    whose area/volume default is an IfcDerivedUnit rather than a literal-UnitType-matching
-    IfcSIUnit/IfcConversionBasedUnit has no literal UnitType to match on.
-    ifcopenshell.util.unit.get_project_unit() used to only match by literal UnitType, so the
-    read-only unit symbol and the edit-mode "Default (<symbol>)" picker entry both silently
-    fell back to no symbol at all in that case.
-    """
-
-    def setup_project_with_derived_area_and_volume(self, ifc):
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        area = ifcopenshell.api.unit.add_derived_unit(ifc, "USERDEFINED", "area-ish", {length: 2})
-        volume = ifcopenshell.api.unit.add_derived_unit(ifc, "USERDEFINED", "volume-ish", {length: 3})
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length, area, volume])
-
-    def test_default_picker_entry_shows_the_resolved_symbol(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        self.setup_project_with_derived_area_and_volume(ifc)
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcAreaMeasure(5.0))
-        metadata = import_single_property(ifc, element, prop)
-
-        items = bonsai.bim.prop.get_attribute_unit_enum_items(metadata, bpy.context)
-        assert items[0][1] == "Default (m2)"
-
-    def test_read_only_display_resolves_the_symbol(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        self.setup_project_with_derived_area_and_volume(ifc)
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcVolumeMeasure(5.0))
-        metadata = import_single_property(ifc, element, prop)
-
-        assert metadata.unit_symbol == "m3"
-        assert metadata.display_name == "Foo, m3"
-
-
-class TestUpdateAttributeUnitId(NewFile):
-    def test_syncs_unit_id_and_converts_float_value_when_unit_id_enum_changes(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcLengthMeasure(2500.0))
-        metadata = import_single_property(ifc, element, prop)
-        assert metadata.unit_id == 0
-        assert metadata.float_value == 2500.0
-        assert metadata.unit_symbol == "mm"
-        assert metadata.display_name == "Foo, mm"
-
-        metadata.unit_id_enum = str(length_m.id())
-
-        assert metadata.unit_id == length_m.id()
-        assert metadata.float_value == pytest.approx(2.5)  # converted, not just relabeled
-        # Regression test: unit_symbol/display_name used to be a snapshot taken once at import
-        # time, so picking a different unit converted the value but left the label showing the
-        # old unit's symbol.
-        assert metadata.unit_symbol == "m"
-        assert metadata.display_name == "Foo, m"
-
-
-class TestUnitSymbolReflectsLiveProjectState(NewFile):
-    def test_symbol_updates_after_a_project_default_unit_is_assigned_later(self):
-        # Regression test: unit_symbol used to be a snapshot computed once at import time, so a
-        # property/quantity imported before its measure type had a project default unit assigned
-        # kept showing no symbol even after one was added, unless the panel was closed and
-        # reopened (re-triggering import). It's now computed fresh on every access.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        # No AREAUNIT assigned yet.
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcAreaMeasure(5.0))
-        metadata = import_single_property(ifc, element, prop)
-        assert metadata.unit_symbol == ""
-        assert metadata.display_name == "Foo"
-
-        area = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="AREAUNIT")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[area])
-
-        assert metadata.unit_symbol == "m2"
-        assert metadata.display_name == "Foo, m2"
-
-
-class TestImportPsetFromExistingWithAGenericNumericValueAndAnExplicitUnit(NewFile):
-    def test_run(self):
-        # Regression test: some property set specifications declare a property as a generic
-        # IfcReal rather than a proper measure class, relying on an explicit Unit attribute
-        # alone to convey the dimension. get_property_unit() already handled this fine for
-        # display (it checks prop.Unit before looking at NominalValue's type at all), but
-        # get_special_type_for_prop() only looked at NominalValue's class ending in "Measure"
-        # -- so special_type came back "", the picker never appeared, and the real Unit
-        # override never got seeded into unit_id even though it was legitimately set.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(
-            Name="Foo", NominalValue=ifc.createIfcReal(150.0), Unit=length_mm
-        )
-        metadata = import_single_property(ifc, element, prop)
-
-        assert metadata.special_type == "LENGTH"
-        assert tool.Pset.is_measurable_special_type(metadata.special_type)
-        assert metadata.unit_symbol == "mm"
-        assert metadata.unit_id == length_mm.id()
-        assert metadata.unit_id_enum == str(length_mm.id())
-
-        items = bonsai.bim.prop.get_attribute_unit_enum_items(metadata, bpy.context)
-        assert str(length_mm.id()) in [i[0] for i in items]
-
-
-class TestImportPsetFromExistingWithAStrayUnitOnANonMeasureProperty(NewFile):
-    def test_run(self):
-        # Regression test: some real-world exporters set a Unit on a property whose
-        # NominalValue isn't actually a measure (e.g. a text classification), which used
-        # to crash import_pset_from_existing with "enum '<id>' not found in ('0')" -- unit_id
-        # was seeded from prop.Unit unconditionally, before the special_type gate that decides
-        # whether Unit is even meaningful for this property.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(
-            Name="Foo", NominalValue=ifc.createIfcLabel("Bar"), Unit=length_m
-        )
-        metadata = import_single_property(ifc, element, prop)  # must not raise
-
-        assert metadata.special_type == ""
-        assert metadata.unit_id == 0
-        assert metadata.unit_id_enum == "0"
-
-
-class TestGetAttributeUnitEnumItemsWithAMismatchedUnit(NewFile):
-    def test_own_unit_is_always_representable_even_if_not_a_normal_candidate(self):
-        # Regression test: a property's own Unit might not satisfy
-        # get_candidate_units_for_special_type's matching (e.g. mismatched UnitType in messy
-        # real-world data). Seeding must never crash trying to select it, and it should still
-        # show up in the picker so the user can see/change it.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        # A LENGTHUNIT attached to a PRESSURE-typed property -- a real mismatch, not a candidate
-        # get_candidate_units_for_special_type("PRESSURE", ...) would ever return.
-        mismatched_unit = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        prop = ifc.createIfcPropertySingleValue(
-            Name="Foo", NominalValue=ifc.createIfcPressureMeasure(5.0), Unit=mismatched_unit
-        )
-        metadata = import_single_property(ifc, element, prop)  # must not raise
-
-        assert metadata.special_type == "PRESSURE"
-        assert metadata.unit_id == mismatched_unit.id()
-        assert metadata.unit_id_enum == str(mismatched_unit.id())
-
-        items = bonsai.bim.prop.get_attribute_unit_enum_items(metadata, bpy.context)
-        assert str(mismatched_unit.id()) in [i[0] for i in items]
@@ -20,9 +20,6 @@ import bpy
 import ifcopenshell
 import ifcopenshell.api
 import ifcopenshell.api.pset
-import ifcopenshell.api.root
-import ifcopenshell.api.unit
-import pytest

 import bonsai.core.tool
 import bonsai.tool as tool
@@ -55,340 +52,3 @@ class TestIsPsetEmpty(NewFile):
        assert subject.is_pset_empty(pset) is False
        ifcopenshell.api.pset.edit_pset(ifc, pset=pset, properties={"Foo": None})
        assert subject.is_pset_empty(pset) is True
-
-
-class TestEditingAnOverriddenUnitPropertyRoundTrips(NewFile):
-    def test_run(self):
-        # Project default is mm, but this property is authored directly in m.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        pset = ifcopenshell.api.pset.add_pset(ifc, product=element, name="Pset_Test")
-        prop = ifc.createIfcPropertySingleValue(
-            Name="Foo", NominalValue=ifc.createIfcLengthMeasure(2.5), Unit=length_m
-        )
-        pset.HasProperties = [prop]
-
-        obj = bpy.data.objects.new("Wall", None)
-        tool.Ifc.link(element, obj)
-        blender_props = obj.PsetProperties
-        subject.import_pset_from_existing(pset, blender_props, None)
-
-        metadata = blender_props.properties["Foo"].metadata
-        assert metadata.unit_symbol == "m"
-        assert metadata.float_value == 2.5  # raw stored value, not rescaled to the project's mm
-
-        # Simulate a user edit in the property editor.
-        metadata.float_value = 3.5
-
-        # Simulate what EditPset.execute() does: collect the raw value straight
-        # off the metadata and write it back, with no rescaling step.
-        properties = {"Foo": metadata.get_value()}
-        ifcopenshell.api.pset.edit_pset(ifc, pset=pset, properties=properties)
-
-        assert prop.NominalValue.wrappedValue == 3.5  # not rescaled to 3500mm
-        assert prop.Unit == length_m  # override preserved
-
-
-class TestImportingATemplatedQuantityRespectsItsOwnUnitOverride(NewFile):
-    def test_run(self):
-        # Regression test: import_pset_from_template's Q_ branch used to
-        # unconditionally re-template existing quantities, which shadowed
-        # their own Unit override with the project default -- edit mode
-        # showed "m" while the read-only panel correctly showed "mm".
-        # Project default is m, but this quantity is authored directly in mm.
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_m])
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-
-        element = ifc.createIfcBeam()
-        qto = ifcopenshell.api.pset.add_qto(ifc, product=element, name="Qto_Test")
-        quantity = ifc.createIfcQuantityLength(Name="Foo", Unit=length_mm, LengthValue=2500.0)
-        qto.Quantities = [quantity]
-
-        pset_template = ifc.createIfcPropertySetTemplate(
-            Name="Qto_Test",
-            TemplateType="PSET_TYPEDRIVENOVERRIDE",
-            ApplicableEntity="IfcBeam",
-            HasPropertyTemplates=[ifc.createIfcSimplePropertyTemplate(Name="Foo", TemplateType="Q_LENGTH")],
-        )
-
-        obj = bpy.data.objects.new("Beam", None)
-        tool.Ifc.link(element, obj)
-        blender_props = obj.PsetProperties
-        # Mirrors core/pset.py's enable_pset_editing: template pass, then existing-data pass.
-        subject.import_pset_from_template(pset_template, qto, blender_props)
-        subject.import_pset_from_existing(qto, blender_props, pset_template)
-
-        assert len(blender_props.properties) == 1  # not duplicated by the template pass
-        metadata = blender_props.properties["Foo"].metadata
-        assert metadata.unit_symbol == "mm"  # the quantity's own override, not the project default "m"
-        assert metadata.float_value == 2500.0  # raw stored value, not rescaled
-
-
-class TestIsMeasurableSpecialType(NewFile):
-    def test_run(self):
-        for special_type in ("", "DATE", "DATETIME", "LOGICAL", "URI", "DURATION"):
-            assert subject.is_measurable_special_type(special_type) is False
-        assert subject.is_measurable_special_type("LENGTH") is True
-        assert subject.is_measurable_special_type("PRESSURE") is True
-
-
-class TestGetCandidateUnitsForSpecialType(NewFile):
-    def test_returns_candidates_matching_the_special_type(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        ifcopenshell.api.unit.add_si_unit(ifc, unit_type="AREAUNIT")
-        assert set(subject.get_candidate_units_for_special_type("LENGTH", ifc)) == {length_mm, length_m}
-
-    def test_gating_returns_empty_for_non_measurable_special_types(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        assert subject.get_candidate_units_for_special_type("", ifc) == []
-        assert subject.get_candidate_units_for_special_type("URI", ifc) == []
-
-
-class TestResolveEffectiveUnit(NewFile):
-    def test_own_override_takes_precedence_over_project_default(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        assert subject.resolve_effective_unit("LENGTH", length_m.id(), ifc) == length_m
-
-    def test_falls_back_to_project_default_when_unit_id_is_zero(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        assert subject.resolve_effective_unit("LENGTH", 0, ifc) == length_mm
-
-
-class TestConvertAttributeUnit(NewFile):
-    def _new_metadata(self, ifc: ifcopenshell.file):
-        element = ifc.createIfcWall()
-        obj = bpy.data.objects.new("Wall", None)
-        tool.Ifc.link(element, obj)
-        props = obj.PsetProperties
-        new_prop = props.properties.add()
-        new_prop.name = "Foo"
-        return new_prop.metadata
-
-    def test_converts_value_between_two_explicit_units(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        metadata = self._new_metadata(ifc)
-        metadata.special_type = "LENGTH"
-        metadata.unit_id = length_mm.id()
-        metadata.float_value = 2500.0
-
-        subject.convert_attribute_unit(metadata, length_m.id(), ifc)
-        assert metadata.float_value == pytest.approx(2.5)
-
-    def test_converts_value_when_switching_to_and_from_the_project_default(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_m])
-        length_ft = ifcopenshell.api.unit.add_conversion_based_unit(ifc, name="foot")
-
-        metadata = self._new_metadata(ifc)
-        metadata.special_type = "LENGTH"
-        metadata.unit_id = length_ft.id()
-        metadata.float_value = 10.0  # 10 ft
-
-        subject.convert_attribute_unit(metadata, 0, ifc)  # 0 = switch to project default (m)
-        assert metadata.float_value == pytest.approx(3.048)
-
-    def test_noop_when_old_and_new_resolve_to_the_same_unit(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_m])
-
-        metadata = self._new_metadata(ifc)
-        metadata.special_type = "LENGTH"
-        metadata.unit_id = 0  # already resolves to length_m (the project default)
-        metadata.float_value = 5.0
-
-        subject.convert_attribute_unit(metadata, length_m.id(), ifc)
-        assert metadata.float_value == 5.0
-
-    def test_noop_for_a_non_measurable_special_type(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        metadata = self._new_metadata(ifc)
-        metadata.special_type = ""
-        metadata.unit_id = 0
-        metadata.float_value = 5.0
-
-        subject.convert_attribute_unit(metadata, length_m.id(), ifc)
-        assert metadata.float_value == 5.0
-
-
-def _build_wrapped_properties_from_ui(blender_props) -> dict:
-    """Mirrors EditPset._execute()'s properties-building loop (operator.py)."""
-    properties = {}
-    for entry in blender_props.properties:
-        metadata = entry.metadata
-        value = metadata.get_value()
-        if value is not None and subject.is_measurable_special_type(metadata.special_type):
-            unit = tool.Ifc.get().by_id(metadata.unit_id) if metadata.unit_id else None
-            value = {"NominalValue": value, "Unit": unit}
-        properties[metadata.name] = value
-    return properties
-
-
-class TestEditPsetWithUnitOverridePicker(NewFile):
-    def test_picking_a_different_unit_converts_the_displayed_value_and_writes_it_back(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        pset = ifcopenshell.api.pset.add_pset(ifc, product=element, name="Pset_Test")
-        prop = ifc.createIfcPropertySingleValue(Name="Foo", NominalValue=ifc.createIfcLengthMeasure(2500.0))
-        pset.HasProperties = [prop]
-
-        obj = bpy.data.objects.new("Wall", None)
-        tool.Ifc.link(element, obj)
-        blender_props = obj.PsetProperties
-        subject.import_pset_from_existing(pset, blender_props, None)
-
-        metadata = blender_props.properties["Foo"].metadata
-        assert metadata.unit_id == 0
-        assert metadata.float_value == 2500.0
-
-        # Simulate the user picking "m" in the unit picker dropdown.
-        metadata.unit_id_enum = str(length_m.id())
-        assert metadata.float_value == pytest.approx(2.5)  # converted live, not just relabeled
-        assert metadata.unit_id == length_m.id()
-
-        properties = _build_wrapped_properties_from_ui(blender_props)
-        ifcopenshell.api.pset.edit_pset(ifc, pset=pset, properties=properties)
-
-        assert prop.NominalValue.wrappedValue == pytest.approx(2.5)
-        assert prop.Unit == length_m
-
-    def test_picking_default_after_an_override_converts_back_and_clears_the_unit(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_mm = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT", prefix="MILLI")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_mm])
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-
-        element = ifc.createIfcWall()
-        pset = ifcopenshell.api.pset.add_pset(ifc, product=element, name="Pset_Test")
-        prop = ifc.createIfcPropertySingleValue(
-            Name="Foo", NominalValue=ifc.createIfcLengthMeasure(2.5), Unit=length_m
-        )
-        pset.HasProperties = [prop]
-
-        obj = bpy.data.objects.new("Wall", None)
-        tool.Ifc.link(element, obj)
-        blender_props = obj.PsetProperties
-        subject.import_pset_from_existing(pset, blender_props, None)
-
-        metadata = blender_props.properties["Foo"].metadata
-        assert metadata.unit_id == length_m.id()
-        assert metadata.float_value == 2.5
-
-        # Simulate picking "Default" (mm).
-        metadata.unit_id_enum = "0"
-        assert metadata.float_value == pytest.approx(2500.0)
-        assert metadata.unit_id == 0
-
-        properties = _build_wrapped_properties_from_ui(blender_props)
-        ifcopenshell.api.pset.edit_pset(ifc, pset=pset, properties=properties)
-
-        assert prop.Unit is None
-        assert prop.NominalValue.wrappedValue == pytest.approx(2500.0)
-
-    def test_editing_an_unrelated_sibling_property_does_not_disturb_this_ones_override(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject")
-        length_m = ifcopenshell.api.unit.add_si_unit(ifc, unit_type="LENGTHUNIT")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[length_m])
-        length_ft = ifcopenshell.api.unit.add_conversion_based_unit(ifc, name="foot")
-
-        element = ifc.createIfcWall()
-        pset = ifcopenshell.api.pset.add_pset(ifc, product=element, name="Pset_Test")
-        overridden_prop = ifc.createIfcPropertySingleValue(
-            Name="Foo", NominalValue=ifc.createIfcLengthMeasure(10.0), Unit=length_ft
-        )
-        untouched_prop = ifc.createIfcPropertySingleValue(Name="Bar", NominalValue=ifc.createIfcLengthMeasure(3.0))
-        pset.HasProperties = [overridden_prop, untouched_prop]
-
-        obj = bpy.data.objects.new("Wall", None)
-        tool.Ifc.link(element, obj)
-        blender_props = obj.PsetProperties
-        subject.import_pset_from_existing(pset, blender_props, None)
-
-        # Edit only "Bar", never touching "Foo"'s unit dropdown.
-        blender_props.properties["Bar"].metadata.float_value = 4.0
-
-        properties = _build_wrapped_properties_from_ui(blender_props)
-        ifcopenshell.api.pset.edit_pset(ifc, pset=pset, properties=properties)
-
-        assert overridden_prop.Unit == length_ft  # untouched override survives
-        assert overridden_prop.NominalValue.wrappedValue == 10.0
-        assert untouched_prop.NominalValue.wrappedValue == 4.0
-
-
-class TestEditQtoRoundingLoopPreservesUnitWrappedValues(NewFile):
-    def test_run(self):
-        # Regression test for EditPset._execute()'s qto post-processing loop: it must reach
-        # into {"Unit": ..., "NominalValue": ...}-wrapped values to round them, rather than
-        # treating the whole dict as a bare float/int (which would zero it out).
-        properties = {
-            "Foo": {"NominalValue": 2.123456, "Unit": None},
-            "Bar": 3,
-        }
-        for key, value in properties.items():
-            if value is None:
-                continue
-            is_wrapped = isinstance(value, dict) and "Unit" in value
-            raw = value["NominalValue"] if is_wrapped else value
-            if raw is None:
-                continue
-            if isinstance(raw, float):
-                raw = round(raw, 4)
-            elif not isinstance(raw, int):
-                raw = 0
-            if is_wrapped:
-                value["NominalValue"] = raw
-            else:
-                properties[key] = raw
-        assert properties["Foo"]["NominalValue"] == 2.1235
-        assert properties["Foo"]["Unit"] is None
-        assert properties["Bar"] == 3
@@ -181,42 +181,6 @@ class TestGetCalculatedObjectQuantities(test.bim.bootstrap.NewFile):
        assert quantities["NetVolume"] == 282.517


-class TestGetTargetUnits(test.bim.bootstrap.NewFile):
-    def setup_file(self):
-        ifc = ifcopenshell.file()
-        tool.Ifc.set(ifc)
-        ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcProject", name="Test")
-        return ifc
-
-    def test_default_scene_state_returns_nothing(self):
-        self.setup_file()
-        assert subject.get_target_units() == {}
-
-    def test_setting_a_field_maps_it_to_its_measure_class(self):
-        ifc = self.setup_file()
-        metre = ifc.createIfcSIUnit(None, "LENGTHUNIT", None, "METRE")
-        millimetre = ifc.createIfcSIUnit(None, "LENGTHUNIT", "MILLI", "METRE")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[metre])
-
-        props = tool.Qto.get_qto_props()
-        props.target_unit_length = str(millimetre.id())
-
-        assert subject.get_target_units() == {"IfcLengthMeasure": millimetre}
-
-    def test_untouched_fields_are_excluded(self):
-        ifc = self.setup_file()
-        metre = ifc.createIfcSIUnit(None, "LENGTHUNIT", None, "METRE")
-        millimetre = ifc.createIfcSIUnit(None, "LENGTHUNIT", "MILLI", "METRE")
-        gram = ifc.createIfcSIUnit(None, "MASSUNIT", None, "GRAM")
-        ifcopenshell.api.unit.assign_unit(ifc, units=[metre, gram])
-
-        props = tool.Qto.get_qto_props()
-        props.target_unit_length = str(millimetre.id())
-        props.target_unit_mass = "0"  # explicitly left at "Default"
-
-        assert subject.get_target_units() == {"IfcLengthMeasure": millimetre}
-
-
 class TestGetBaseQto(test.bim.bootstrap.NewFile):
    def test_run(self):
        ifc = ifcopenshell.file()
@@ -288,27 +288,3 @@ class TestGenerateSpace(NewFile):
            )
        )
        assert np.allclose(TEST_VERTS, sorted([tuple(v.co) for v in mesh.vertices]))
-
-    def test_regenerate_space_preserves_z_location(self):
-        bpy.ops.bim.create_project()
-        ifc = tool.Ifc.get()
-        scene = bpy.context.scene
-        product = ifcopenshell.api.root.create_entity(ifc, ifc_class="IfcWall")
-        bpy.ops.mesh.primitive_cube_add(size=10, location=(0, 0, 4))
-        obj = bpy.data.objects["Cube"]
-        scene.collection.objects.link(obj)
-        tool.Ifc.link(product, obj)
-        scene.cursor.location = (0, 0, 0)
-
-        bpy.ops.bim.generate_space()
-        space = bpy.data.objects["IfcSpace/Space"]
-        space.location.z = 5
-        bpy.context.view_layer.update()
-
-        bpy.context.view_layer.objects.active = space
-        space.select_set(True)
-        obj.select_set(False)
-
-        bpy.ops.bim.generate_space()
-
-        assert np.isclose(space.location.z, 5), f"Expected z=5, got {space.location.z}"
@@ -24,7 +24,7 @@ import os
 import types
 from collections import defaultdict
 from collections.abc import Iterable
-from typing import Any, Literal, NamedTuple, Optional, Union, get_args
+from typing import Any, Literal, NamedTuple, Union, get_args

 import ifcopenshell
 import ifcopenshell.api.pset
@@ -127,61 +127,8 @@ def quantify(ifc_file: ifcopenshell.file, elements: set[ifcopenshell.entity_inst
    return results


-def get_quantity_measures(rules: dict) -> dict[str, dict[str, str]]:
-    """Statically derive each quantity's measure class from the rule set that defines it,
-    reading it straight from the calculator's own Function table (the same source the
-    calculator itself used to compute the value) -- not guessed from the quantity name.
-
-    :param rules: A rule set as accepted by :func:`quantify`, e.g. from `ifc5d.qto.rules`.
-    :return: `qto_name -> quantity_name -> measure class` (e.g. "IfcLengthMeasure"), matching
-        the keys used by `SI2ProjectUnitConverter.project_units`.
-    """
-    measures: dict[str, dict[str, str]] = {}
-    for calculator_name, queries in rules.get("calculators", {}).items():
-        calculator = calculators[calculator_name]
-        for _entity_or_query, qtos in queries.items():
-            for qto_name, quantities in qtos.items():
-                for quantity_name, formula in quantities.items():
-                    if not formula:
-                        continue
-                    function = calculator.functions.get(formula)
-                    if function is None:
-                        continue
-                    measures.setdefault(qto_name, {})[quantity_name] = function.measure
-    return measures
-
-
-def _reconvert(ifc_file: ifcopenshell.file, value: float, to_unit: ifcopenshell.entity_instance) -> float:
-    """Re-express `value` (as computed by `SI2ProjectUnitConverter` -- the project's default
-    unit for its dimension, or, if the project has none, raw SI, mirroring `convert()`'s own
-    fallback below) in `to_unit`, which shares `to_unit`'s dimension (`UnitType`).
-    """
-    unit_type = getattr(to_unit, "UnitType", None)
-    from_unit = ifcopenshell.util.unit.get_project_unit(ifc_file, unit_type) if unit_type else None
-    from_scale = ifcopenshell.util.unit.get_unit_scale(from_unit) if from_unit else 1.0  # already SI
-    return value * from_scale / ifcopenshell.util.unit.get_unit_scale(to_unit)
-
-
-def edit_qtos(
-    ifc_file: ifcopenshell.file,
-    results: ResultsDict,
-    target_units: Optional[dict[str, ifcopenshell.entity_instance]] = None,
-    rules: Optional[dict] = None,
-) -> None:
-    """Apply quantification results as quantity sets.
-
-    :param target_units: Optional map of measure class (e.g. "IfcLengthMeasure", matching
-        `SI2ProjectUnitConverter.project_units`'s keys) to a unit to express *newly created*
-        quantities of that measure in, instead of the project default. Ignored unless `rules`
-        is also given (needed to resolve each quantity's measure class -- see
-        `get_quantity_measures`). Has no effect on quantities that already exist -- those are
-        always re-expressed in whatever Unit they already carry (see below), regardless of
-        `target_units`.
-    :param rules: The rule set used to produce `results` (the same object passed to
-        `quantify()`), used only to resolve `target_units` via `get_quantity_measures()`.
-    """
-    quantity_measures = get_quantity_measures(rules) if (target_units and rules) else {}
-
+def edit_qtos(ifc_file: ifcopenshell.file, results: ResultsDict) -> None:
+    """Apply quantification results as quantity sets."""
    for element, qtos in results.items():
        for name, quantities in qtos.items():
            qto = ifcopenshell.util.element.get_pset(element, name, should_inherit=False)
@@ -189,36 +136,7 @@ def edit_qtos(
                qto = ifc_file.by_id(qto["id"])
            else:
                qto = ifcopenshell.api.pset.add_qto(ifc_file, element, name)
-
-            existing_by_name = {q.Name: q for q in (qto.Quantities or ())}
-            wrapped_quantities: dict[str, Any] = {}
-
-            for quantity_name, value in quantities.items():
-                existing_unit = getattr(existing_by_name.get(quantity_name), "Unit", None)
-
-                if existing_unit is not None:
-                    # A quantity that already carries its own Unit override must be
-                    # re-expressed in that unit, not overwritten with a value computed in
-                    # the project default while the stale Unit label stays put.
-                    wrapped_quantities[quantity_name] = {
-                        "NominalValue": _reconvert(ifc_file, value, existing_unit),
-                        "Unit": existing_unit,
-                    }
-                    continue
-
-                measure = quantity_measures.get(name, {}).get(quantity_name)
-                target_unit = target_units.get(measure) if (target_units and measure) else None
-                if target_unit is not None:
-                    # Brand new quantity, proactively expressed in the chosen target unit.
-                    wrapped_quantities[quantity_name] = {
-                        "NominalValue": _reconvert(ifc_file, value, target_unit),
-                        "Unit": target_unit,
-                    }
-                    continue
-
-                wrapped_quantities[quantity_name] = value  # unchanged bare-float path
-
-            ifcopenshell.api.pset.edit_qto(ifc_file, qto=qto, properties=wrapped_quantities)
+            ifcopenshell.api.pset.edit_qto(ifc_file, qto=qto, properties=quantities)


 class SI2ProjectUnitConverter:
@@ -22,7 +22,6 @@ import ifcopenshell
 import ifcopenshell.api.context
 import ifcopenshell.api.root
 import ifcopenshell.api.unit
-import ifcopenshell.util.element
 import pytest

 import ifc5d.qto
@@ -91,141 +90,3 @@ class TestOpeningQuantities:
        assert quantities["Depth"] == pytest.approx(0.3)
        assert quantities["Area"] == pytest.approx(0.5)
        assert quantities["Volume"] == pytest.approx(0.15)
-
-
-class TestGetQuantityMeasures:
-    def test_resolves_measures_from_the_calculator_function_table(self):
-        measures = ifc5d.qto.get_quantity_measures(ifc5d.qto.rules["IFC4X3QtoBaseQuantities"])
-        assert measures["Qto_WallBaseQuantities"]["Length"] == "IfcLengthMeasure"
-        assert measures["Qto_WallBaseQuantities"]["NetWeight"] == "IfcMassMeasure"
-
-
-class TestEditQtos:
-    def setup_method(self):
-        self.file = ifcopenshell.file(schema="IFC4X3")
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject", name="Test")
-        self.wall = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-
-    def get_quantity(self, name: str) -> ifcopenshell.entity_instance:
-        pset = ifcopenshell.util.element.get_pset(self.wall, "Qto_WallBaseQuantities", should_inherit=False)
-        qto = self.file.by_id(pset["id"])
-        return next(q for q in qto.Quantities if q.Name == name)
-
-    def test_new_quantity_with_no_target_unit_is_a_bare_value(self):
-        metre = self.file.createIfcSIUnit(None, "LENGTHUNIT", None, "METRE")
-        ifcopenshell.api.unit.assign_unit(self.file, units=[metre])
-
-        ifc5d.qto.edit_qtos(self.file, {self.wall: {"Qto_WallBaseQuantities": {"Length": 5.0}}})
-
-        quantity = self.get_quantity("Length")
-        assert quantity.LengthValue == pytest.approx(5.0)
-        assert quantity.Unit is None
-
-    def test_existing_manual_unit_override_is_reconverted_not_left_stale(self):
-        metre = self.file.createIfcSIUnit(None, "LENGTHUNIT", None, "METRE")
-        ifcopenshell.api.unit.assign_unit(self.file, units=[metre])
-        millimetre = self.file.createIfcSIUnit(None, "LENGTHUNIT", "MILLI", "METRE")
-
-        ifc5d.qto.edit_qtos(self.file, {self.wall: {"Qto_WallBaseQuantities": {"Length": 5.0}}})
-        quantity = self.get_quantity("Length")
-        # Simulate a user picking a millimetre override via the per-property picker.
-        quantity.Unit = millimetre
-        quantity.LengthValue = 5000.0
-
-        # Re-running take-off recomputes the value in the project default (metres) again --
-        # this must not leave the recomputed metres value mislabeled as millimetres.
-        ifc5d.qto.edit_qtos(self.file, {self.wall: {"Qto_WallBaseQuantities": {"Length": 6.0}}})
-
-        quantity = self.get_quantity("Length")
-        assert quantity.Unit == millimetre
-        assert quantity.LengthValue == pytest.approx(6000.0)
-
-    def test_target_unit_applies_only_to_brand_new_quantities(self):
-        metre = self.file.createIfcSIUnit(None, "LENGTHUNIT", None, "METRE")
-        ifcopenshell.api.unit.assign_unit(self.file, units=[metre])
-        millimetre = self.file.createIfcSIUnit(None, "LENGTHUNIT", "MILLI", "METRE")
-        rules = {"calculators": {"IfcOpenShell": {"IfcWall": {"Qto_WallBaseQuantities": {"Length": "net_get_x"}}}}}
-
-        ifc5d.qto.edit_qtos(
-            self.file,
-            {self.wall: {"Qto_WallBaseQuantities": {"Length": 5.0}}},
-            target_units={"IfcLengthMeasure": millimetre},
-            rules=rules,
-        )
-
-        quantity = self.get_quantity("Length")
-        assert quantity.Unit == millimetre
-        assert quantity.LengthValue == pytest.approx(5000.0)
-
-    def test_target_units_are_ignored_without_rules(self):
-        metre = self.file.createIfcSIUnit(None, "LENGTHUNIT", None, "METRE")
-        ifcopenshell.api.unit.assign_unit(self.file, units=[metre])
-        millimetre = self.file.createIfcSIUnit(None, "LENGTHUNIT", "MILLI", "METRE")
-
-        # `rules` is required to resolve a quantity's measure class -- without it, target_units
-        # has nothing to key off, so brand new quantities fall back to today's bare-float path.
-        ifc5d.qto.edit_qtos(
-            self.file,
-            {self.wall: {"Qto_WallBaseQuantities": {"Length": 5.0}}},
-            target_units={"IfcLengthMeasure": millimetre},
-        )
-
-        quantity = self.get_quantity("Length")
-        assert quantity.Unit is None
-        assert quantity.LengthValue == pytest.approx(5.0)
-
-    def test_reconvert_treats_a_missing_project_default_as_raw_si(self):
-        # No LENGTHUNIT is assigned to the project at all, so SI2ProjectUnitConverter.convert()
-        # would have left the calculated value as raw SI (metres) -- _reconvert must match.
-        millimetre = self.file.createIfcSIUnit(None, "LENGTHUNIT", "MILLI", "METRE")
-        rules = {"calculators": {"IfcOpenShell": {"IfcWall": {"Qto_WallBaseQuantities": {"Length": "net_get_x"}}}}}
-
-        ifc5d.qto.edit_qtos(
-            self.file,
-            {self.wall: {"Qto_WallBaseQuantities": {"Length": 5.0}}},
-            target_units={"IfcLengthMeasure": millimetre},
-            rules=rules,
-        )
-
-        quantity = self.get_quantity("Length")
-        assert quantity.LengthValue == pytest.approx(5000.0)
-
-
-class TestEditQtosIntegration:
-    """A real quantify() + edit_qtos() round trip, guarding against edit_qto's own
-    class-inference disagreeing with get_quantity_measures()'s notion of measure.
-    """
-
-    def test_target_unit_produces_the_correct_quantity_class(self):
-        file = ifcopenshell.file(schema="IFC4X3")
-        ifcopenshell.api.root.create_entity(file, ifc_class="IfcProject", name="Test")
-        metre = file.createIfcSIUnit(None, "LENGTHUNIT", None, "METRE")
-        sqm = file.createIfcSIUnit(None, "AREAUNIT", None, "SQUARE_METRE")
-        cum = file.createIfcSIUnit(None, "VOLUMEUNIT", None, "CUBIC_METRE")
-        ifcopenshell.api.unit.assign_unit(file, units=[metre, sqm, cum])
-        model = ifcopenshell.api.context.add_context(file, context_type="Model")
-        body = ifcopenshell.api.context.add_context(
-            file, context_type="Model", context_identifier="Body", target_view="MODEL_VIEW", parent=model
-        )
-
-        wall = ifcopenshell.api.root.create_entity(file, ifc_class="IfcWall")
-        wall.ObjectPlacement = file.createIfcLocalPlacement(
-            None, file.createIfcAxis2Placement3D(file.createIfcCartesianPoint((0.0, 0.0, 0.0)), None, None)
-        )
-        profile = file.createIfcRectangleProfileDef("AREA", None, None, 5.0, 0.2)
-        position = file.createIfcAxis2Placement3D(file.createIfcCartesianPoint((0.0, 0.0, 0.0)), None, None)
-        solid = file.createIfcExtrudedAreaSolid(profile, position, file.createIfcDirection((0.0, 0.0, 1.0)), 3.0)
-        rep = file.createIfcShapeRepresentation(body, "Body", "SweptSolid", [solid])
-        wall.Representation = file.createIfcProductDefinitionShape(None, None, [rep])
-
-        millimetre = file.createIfcSIUnit(None, "LENGTHUNIT", "MILLI", "METRE")
-        rules = ifc5d.qto.rules["IFC4X3QtoBaseQuantities"]
-        results = ifc5d.qto.quantify(file, {wall}, rules)
-        ifc5d.qto.edit_qtos(file, results, target_units={"IfcLengthMeasure": millimetre}, rules=rules)
-
-        pset = ifcopenshell.util.element.get_pset(wall, "Qto_WallBaseQuantities", should_inherit=False)
-        qto = file.by_id(pset["id"])
-        length = next(q for q in qto.Quantities if q.Name == "Length")
-        assert length.is_a("IfcQuantityLength")
-        assert length.Unit == millimetre
-        assert length.LengthValue == pytest.approx(5000.0)
@@ -94,15 +94,9 @@ def list_functions(module: str) -> list[dict]:


 def function_docs(module: str, function: str) -> dict:
-    """Show the full documentation for one ifcopenshell.api function.
+    """Full documentation for a single API function.

-    Returns the summary and long description, every parameter with its type,
-    default and description, and the return type. Read this before calling
-    ``run_api()`` so that parameter names and value types are correct.
-
-    :param module: API module name, for example ``'root'``.
-    :param function: Function name within the module, for example
-        ``'create_entity'``.
+    Returns a dict with: module, function, description, params (with types/defaults/descriptions), return_type
    """
    fn = _get_underlying_function(module, function)
    if fn is None:
@@ -14,21 +14,10 @@ def list_rules() -> list[dict[str, str]]:


 def run_quantify(model: ifcopenshell.file, rule: str, selector: str | None = None) -> dict[str, Any]:
-    """Compute base quantities for elements and write them into the model.
+    """Run quantity take-off on the model using the named rule.

-    This is a write operation: it derives lengths, areas and volumes from
-    element geometry and adds or updates their ``IfcElementQuantity`` sets.
-    It does not report a schedule — see ``ifcquery.schedule()`` for the
-    construction programme and ``ifcquery.cost()`` for cost schedules. An
-    unrecognised ``rule`` is reported as an error listing the rules that are
-    available.
-
-    :param model: The in-memory IFC model. Modified in-place.
-    :param rule: Quantity take-off rule set, for example
-        ``'IFC4QtoBaseQuantities'`` or ``'IFC4X3QtoBaseQuantities'``.
-    :param selector: ifcopenshell selector restricting which elements are
-        measured, e.g. ``'IfcWall'``. Omit to measure every ``IfcElement`` and
-        ``IfcSpace``.
+    Modifies the model in-place by adding/updating IfcElementQuantity psets.
+    Returns a summary dict with ok, rule, and elements_quantified.
    """
    from ifc5d.qto import edit_qtos, quantify
    from ifc5d.qto import rules as rule_sets
@@ -832,7 +832,7 @@ bool IfcGeom::util::points_on_planar_face_generator::operator()(gp_Pnt& p) {
 }


-bool IfcGeom::util::boolean_operation(const boolean_settings& settings, const TopoDS_Shape& a_input, const NCollection_List<TopoDS_Shape>& b_input, BOPAlgo_Operation op, TopoDS_Shape& result, double fuzziness) {
+bool IfcGeom::util::boolean_operation(const boolean_settings& settings, const TopoDS_Shape& a_input, const NCollection_List<TopoDS_Shape>& b_input, BOPAlgo_Operation op, TopoDS_Shape& result, double fuzziness, bool retry_sequentially_on_failure) {
 	using namespace std::string_literals;

 	const bool do_unify = true;
@@ -1417,7 +1417,37 @@ bool IfcGeom::util::boolean_operation(const boolean_settings& settings, const To
 	}
 	if (!success) {
 		if (allow_retry) {
-			return boolean_operation(settings, a, b, op, result, new_fuzziness);
+			return boolean_operation(settings, a, b, op, result, new_fuzziness, retry_sequentially_on_failure);
+		} else if (op == BOPAlgo_CUT && retry_sequentially_on_failure && b.Extent() > 1) {
+			// #487: a batched cut with multiple simultaneous tool operands (see
+			// OpenCascadeKernel::convert_openings, which groups openings by
+			// similar edge length) can fail every fuzziness attempt above even
+			// when each tool cuts the operand individually without issue. Retry
+			// by applying the tools one at a time instead, feeding the result of
+			// each cut into the next. b.Extent() > 1 both gates this to genuine
+			// multi-tool batches and guards against re-entering this branch,
+			// since every sequential sub-cut below has exactly one tool operand.
+			settings.log().Notice("GEO", 403, "Retrying cut with " + std::to_string(b.Extent()) + " operands applied sequentially");
+
+			TopoDS_Shape sequential_result = a;
+			bool sequential_ok = true;
+			NCollection_List<TopoDS_Shape>::Iterator it(b);
+			for (; it.More(); it.Next()) {
+				TopoDS_Shape step_result;
+				if (!boolean_operation(settings, sequential_result, it.Value(), op, step_result)) {
+					sequential_ok = false;
+					break;
+				}
+				sequential_result = step_result;
+			}
+
+			if (sequential_ok) {
+				settings.log().Notice("GEO", 404, "Sequential opening subtraction fallback succeeded");
+				result = sequential_result;
+				return true;
+			}
+
+			settings.log().Notice("GEO", 154, "No longer attempting boolean operation with higher fuzziness");
 		} else {
 			settings.log().Notice("GEO", 154, "No longer attempting boolean operation with higher fuzziness");
 		}
@@ -104,7 +104,7 @@ namespace IfcGeom {
 			Logger& log() const { return logger ? *logger : Logger::Root(); }
 		};

-		bool boolean_operation(const boolean_settings& settings, const TopoDS_Shape&, const NCollection_List<TopoDS_Shape>&, BOPAlgo_Operation, TopoDS_Shape&, double fuzziness = -1.);
+		bool boolean_operation(const boolean_settings& settings, const TopoDS_Shape&, const NCollection_List<TopoDS_Shape>&, BOPAlgo_Operation, TopoDS_Shape&, double fuzziness = -1., bool retry_sequentially_on_failure = true);

 		bool boolean_operation(const boolean_settings& settings, const TopoDS_Shape&, const TopoDS_Shape&, BOPAlgo_Operation, TopoDS_Shape&, double fuzziness = -1.);

@@ -13,14 +13,6 @@ namespace ifcopenshell {
 			profile_point(const std::array<double, 2>& p, const boost::optional<double>& r = boost::none)
 				: xy(p), radius(r) {
 			}
-
-			// Recent Boost makes optional's converting constructor explicit,
-			// and an explicit constructor cannot be used in copy-initialization
-			// - which is what `{{x, y}, {radius}}` in the profile mappings is.
-			// Taking the double directly keeps every call site working.
-			profile_point(const std::array<double, 2>& p, double r)
-				: xy(p), radius(r) {
-			}
 		};

 		struct profile_point_with_edges {
@@ -35,27 +35,6 @@ from ifcquery import (
 from ifcquery import validate as validate_mod


-def _use_doc(source: Callable, extra: str = "") -> Callable:
-    """Decorator: copy `source`'s docstring onto the decorated method.
-
-    Keeps the query/edit logic in ``ifcquery``/``ifcedit`` as the single
-    source of truth for what a delegating ``IfcSession`` method does, rather
-    than maintaining a second prose description here. Only ``__doc__`` is
-    copied — unlike `functools.wraps`, this leaves the method's own signature
-    (and MCP tool schema derived from it) untouched.
-
-    :param extra: Optional session-specific note appended after `source`'s
-        docstring, for the handful of methods that translate an argument
-        (e.g. a JSON/MCP-friendly default) before delegating.
-    """
-
-    def decorator(fn: Callable) -> Callable:
-        fn.__doc__ = (source.__doc__ or "").rstrip() + extra
-        return fn
-
-    return decorator
-
-
 def _jsonify(x: Any) -> Any:
    """Convert IfcOpenShell objects / iterables into JSON-safe primitives."""
    if x is None or isinstance(x, (str, int, float, bool)):
@@ -252,47 +231,20 @@ class IfcSession:
        return self.model

    def ifc_new(self, schema: str = "IFC4") -> dict[str, Any]:
-        """Create a new empty IFC model in memory.
-
-        Replaces the model currently held by the session, discarding any unsaved
-        edits. The new model has no file path of its own, so ``ifc_save`` must be
-        given an explicit path.
-
-        :param schema: IFC schema version — ``IFC2X3``, ``IFC4``, ``IFC4X1``,
-            ``IFC4X2`` or ``IFC4X3`` — passed straight to ``ifcopenshell.file()``
-            (default ``IFC4``). ``IFC4X3_ADD2`` is also accepted and, like
-            ``IFC4X3``, produces a model whose ``schema`` reports ``IFC4X3``.
-        """
+        """Create a new empty IFC model in memory."""
        self.model = ifcopenshell.file(schema=schema)
        self.model_path = None
        return {"ok": True, "schema": self.model.schema, "entities": sum(1 for _ in self.model)}

    def ifc_load(self, path: str) -> str:
-        """Open an IFC file from disk into the session.
-
-        Replaces the model currently held by the session, discarding any unsaved
-        edits, and remembers the path so a later ``ifc_save`` can overwrite it.
-        Call this before any query or edit method. Returns a confirmation string
-        naming the schema version and entity count.
-
-        :param path: Filesystem path of the IFC file to open.
-        """
+        """Open an IFC file into memory. Returns confirmation string."""
        self.model = ifcopenshell.open(path)
        self.model_path = path
        count = sum(1 for _ in self.model)
        return f"Loaded {path}: schema {self.model.schema}, {count} entities"

    def ifc_save(self, path: str = "") -> str:
-        """Write the in-memory model to disk.
-
-        Overwrites the target file without further confirmation. Edits made by
-        ``ifc_edit``, ``ifc_shape`` and ``ifc_quantify`` exist only in memory
-        until this is called.
-
-        :param path: Destination path. Omit to overwrite the file the model was
-            loaded from; this fails for a model created by ``ifc_new``, which has
-            no original path.
-        """
+        """Write the in-memory model to disk. Empty path overwrites the original file."""
        model = self._require_model()
        target = path if path else self.model_path
        if not target:
@@ -301,11 +253,7 @@ class IfcSession:
        return f"Saved to {target}"

    def ifc_reset(self) -> dict[str, Any]:
-        """Discard the in-memory model.
-
-        Drops the model and its file path, throwing away any edits not already
-        written with ``ifc_save``. Succeeds even when no model is loaded.
-        """
+        """Drop the in-memory model."""
        self.model = None
        self.model_path = None
        return {"ok": True}
@@ -313,42 +261,39 @@ class IfcSession:
    # -------------
    # Query tools
    # -------------
-    @_use_doc(summary.summary)
    def ifc_summary(self) -> dict[str, Any]:
+        """Model overview: schema, entity counts, project info."""
        return summary.summary(self._require_model())

-    @_use_doc(tree.tree)
    def ifc_tree(self) -> dict[str, Any] | list[dict[str, Any]]:
+        """Full spatial hierarchy tree (Project -> Site -> Building -> Storeys -> Elements)."""
        return tree.tree(self._require_model())

-    @_use_doc(info.info)
    def ifc_info(self, element_id: int) -> dict[str, Any]:
+        """Deep inspection of an entity by step ID (attributes, psets, placement, type, material)."""
        model = self._require_model()
        element = model.by_id(element_id)
        if element is None:
            raise IfcSessionError(f"Element #{element_id} not found.")
        return info.info(model, element)

-    @_use_doc(select.select)
    def ifc_select(self, query: str) -> list[dict[str, Any]]:
+        """Filter elements using ifcopenshell selector syntax.
+
+        Examples: ``IfcWall``, ``IfcWall, IfcColumn``, ``! IfcWall``,
+        ``IfcWall, Name = "My Wall"``, ``type = "Concrete Wall"``,
+        ``material = "Concrete"``.
+        """
        return select.select(self._require_model(), query)

-    @_use_doc(relations.relations)
    def ifc_relations(self, element_id: int, traverse: str = "") -> dict[str, Any] | list[dict[str, Any]]:
+        """Show relationships for an element. Set traverse='up' to walk hierarchy to IfcProject."""
        model = self._require_model()
        element = model.by_id(element_id)
        if element is None:
            raise IfcSessionError(f"Element #{element_id} not found.")
        return relations.relations(model, element, traverse=traverse if traverse else None)

-    @_use_doc(
-        clash_mod.clash,
-        extra=(
-            "\n\nNote: this method takes a plain ``clearance: float`` rather than\n"
-            '``clearance: float | None`` — ``0.0`` (the default) means "skip the\n'
-            'clearance check", matching ``None`` in ``ifcquery.clash.clash()``.'
-        ),
-    )
    def ifc_clash(
        self,
        element_id: int,
@@ -356,6 +301,7 @@ class IfcSession:
        tolerance: float = 0.002,
        scope: str = "storey",
    ) -> dict[str, Any]:
+        """Check element for geometric clashes. clearance=0.0 means no clearance check."""
        model = self._require_model()
        element = model.by_id(element_id)
        if element is None:
@@ -368,53 +314,33 @@ class IfcSession:
            scope=scope,
        )

-    @_use_doc(contexts_mod.contexts)
    def ifc_contexts(self) -> list[dict[str, Any]]:
+        """List all geometric representation contexts and subcontexts with their step IDs."""
        return contexts_mod.contexts(self._require_model())

-    @_use_doc(materials_mod.materials)
    def ifc_materials(self) -> list[dict[str, Any]]:
+        """List all materials and material sets (layers, constituents, profiles)."""
        return materials_mod.materials(self._require_model())

    # ------------------------
    # Edit discovery + execute
    # ------------------------
    def ifc_list(self, module: str = "") -> list[dict]:
-        """Discover the ifcopenshell.api functions available for editing.
-
-        With no argument returns every API module with its description,
-        function names and function count. With a module name returns that
-        module's functions, each with a one-line description and its
-        parameters. This is the starting point for ``ifc_docs`` and
-        ``ifc_edit``; it inspects the installed ifcopenshell package and works
-        without a model loaded.
-
-        :param module: API module name, for example ``'root'``, ``'geometry'``
-            or ``'pset'``. Omit to list all modules.
-        """
+        """List all API modules, or functions within a module. Empty module = all modules."""
        return list_functions(module) if module else list_modules()

-    @_use_doc(function_docs)
    def ifc_docs(self, function_path: str) -> dict:
+        """Show full documentation for an API function. Input format: 'module.function'."""
        module, function = function_path.split(".", 1)
        return function_docs(module, function)

    def ifc_edit(self, function_path: str, params: Any = "{}") -> dict:
-        """Run an ifcopenshell.api function to modify the model.
+        """Execute an ifcopenshell.api mutation.

-        This is the general-purpose edit method; use ``ifc_list`` and
-        ``ifc_docs`` first to find the function and its parameters. Changes
-        are made to the in-memory model only, so ``ifc_save`` is needed to
-        persist them. Returns ``{"ok": True, "result": ...}``, or
-        ``{"ok": False, "error": ...}`` when the function is unknown, a
-        parameter cannot be converted, or the call raises.
-
-        :param function_path: ``'module.function'``, for example
-            ``'root.create_entity'``.
-        :param params: Keyword arguments as a JSON string, a dict (tool
-            calling) or a JsProxy (handled upstream in embedded.py). Pass
-            entity references as integer step IDs, and arguments typed as an
-            IFC file as a file path string.
+        params may be:
+        - JSON string
+        - dict (from tool calling / JS)
+        - JsProxy (handled upstream in embedded.py)
        """
        model = self._require_model()
        module, function = function_path.split(".", 1)
@@ -433,20 +359,28 @@ class IfcSession:
    # ------------------------
    # Extended query + edit tools
    # ------------------------
-    @_use_doc(validate_mod.validate)
    def ifc_validate(self, express_rules: bool = False) -> dict[str, Any]:
+        """Validate the loaded model. Returns {'valid': bool, 'issues': [...]}."""
        return validate_mod.validate(self._require_model(), express_rules=express_rules)

-    @_use_doc(schedule.schedule)
    def ifc_schedule(self, max_depth: int | None = None) -> list[dict[str, Any]]:
+        """List work schedules and nested tasks from the model.
+
+        max_depth limits subtask expansion (None = unlimited). At the cutoff,
+        subtasks is replaced with {"truncated": True, "count": N}.
+        """
        return schedule.schedule(self._require_model(), max_depth=max_depth)

-    @_use_doc(cost_mod.cost)
    def ifc_cost(self, max_depth: int | None = None) -> list[dict[str, Any]]:
+        """List cost schedules and nested cost items from the model.
+
+        max_depth limits cost item expansion (None = unlimited). At the cutoff,
+        subitems is replaced with {"truncated": True, "count": N}.
+        """
        return cost_mod.cost(self._require_model(), max_depth=max_depth)

-    @_use_doc(schema.schema)
    def ifc_schema(self, entity_type: str) -> dict[str, Any]:
+        """Return IFC class documentation for entity_type using the model's schema version."""
        return schema.schema(self._require_model(), entity_type)

    def ifc_plot(
@@ -522,43 +456,18 @@ class IfcSession:
    # Shape builder tools
    # ------------------------
    def ifc_shape_list(self) -> list[dict]:
-        """List the ShapeBuilder methods available for constructing geometry.
-
-        Returns every public ``ifcopenshell.util.shape_builder.ShapeBuilder``
-        method with a one-line description and its parameter names, read
-        directly from that class's own docstrings. Use it to find a method,
-        then ``ifc_shape_docs`` for the details and ``ifc_shape`` to call it.
-        Works without a model loaded.
-        """
+        """List all ShapeBuilder geometry methods with one-line descriptions and parameter names."""
        return _list_shape_methods()

    def ifc_shape_docs(self, method: str) -> dict:
-        """Show the full documentation for one ShapeBuilder method.
-
-        Returns the summary and long description, every parameter with its
-        type and default, and the return type — read directly from
-        ``ShapeBuilder``'s own docstring. Read this before ``ifc_shape`` so
-        that argument names and value shapes are correct. Works without a
-        model loaded.
-
-        :param method: ShapeBuilder method name, for example ``'polyline'``,
-            ``'rectangle'`` or ``'extrude'``.
-        """
+        """Full documentation for a ShapeBuilder method: params, types, return value."""
        return _shape_method_docs(method)

    def ifc_shape(self, method: str, params: Any = "{}") -> dict:
-        """Call a ShapeBuilder method to build geometry in the model.
+        """Call a ShapeBuilder method by name. Returns the created entity's step ID.

-        The created entities are added to the in-memory model, so
-        ``ifc_save`` is needed to persist them. On success the result
-        identifies the created entity by step ID and type; an unknown method
-        or a failed call is reported as an error instead.
-
-        :param method: ShapeBuilder method name, as listed by
-            ``ifc_shape_list``.
-        :param params: JSON string of keyword arguments. Pass entity
-            references as integer step IDs and vectors as JSON arrays, e.g.
-            ``[1.0, 0.0, 0.0]``.
+        params is a JSON string of keyword arguments. Pass entity references as integer
+        step IDs; vectors as JSON arrays (e.g. [1.0, 0.0, 0.0]).
        """
        model = self._require_model()

@@ -584,8 +493,11 @@ class IfcSession:
        except Exception as e:
            return {"ok": False, "error": f"{type(e).__name__}: {e}"}

-    @_use_doc(run_quantify, extra="\n\nCall ``ifc_save`` afterwards to persist the result.")
    def ifc_quantify(self, rule: str, selector: str = "") -> dict[str, Any]:
+        """Run quantity take-off on the model using the named rule.
+
+        Modifies the model in-place; call ifc_save() after.
+        """
        model = self._require_model()
        return run_quantify(model, rule, selector=selector if selector else None)

@@ -2,7 +2,6 @@
 from __future__ import annotations

 import base64
-import inspect
 from typing import Any

 from ifcmcp.core import IfcSession
@@ -10,7 +9,7 @@ from ifcmcp.core import IfcSession
 try:
    from mcp.server.fastmcp import FastMCP  # type: ignore
    from mcp.types import ImageContent  # type: ignore
-except ImportError:  # pragma: no cover
+except Exception:  # pragma: no cover
    FastMCP = None  # type: ignore
    ImageContent = None  # type: ignore

@@ -24,11 +23,6 @@ def build_server() -> Any:

    session = IfcSession()

-    def _tool(fn):
-        """Register a tool, taking its MCP description from the identically-named
-        IfcSession method rather than duplicating it here."""
-        return server.tool(description=inspect.getdoc(getattr(IfcSession, fn.__name__)))(fn)
-
    server = FastMCP(
        name="ifc-mcp",
        instructions=(
@@ -39,44 +33,44 @@ def build_server() -> Any:
    )

    # ---- Lifecycle ----
-    @_tool
+    @server.tool()
    def ifc_new(schema: str = "IFC4") -> dict[str, Any]:
        return session.ifc_new(schema=schema)

-    @_tool
+    @server.tool()
    def ifc_load(path: str) -> str:
        return session.ifc_load(path)

-    @_tool
+    @server.tool()
    def ifc_save(path: str = "") -> str:
        return session.ifc_save(path)

-    @_tool
+    @server.tool()
    def ifc_reset() -> dict[str, Any]:
        return session.ifc_reset()

    # ---- Query ----
-    @_tool
+    @server.tool()
    def ifc_summary() -> dict[str, Any]:
        return session.ifc_summary()

-    @_tool
+    @server.tool()
    def ifc_tree() -> dict[str, Any] | list[dict[str, Any]]:
        return session.ifc_tree()

-    @_tool
+    @server.tool()
    def ifc_info(element_id: int) -> dict[str, Any]:
        return session.ifc_info(element_id)

-    @_tool
+    @server.tool()
    def ifc_select(query: str) -> list[dict[str, Any]]:
        return session.ifc_select(query)

-    @_tool
+    @server.tool()
    def ifc_relations(element_id: int, traverse: str = "") -> dict[str, Any] | list[dict[str, Any]]:
        return session.ifc_relations(element_id, traverse=traverse)

-    @_tool
+    @server.tool()
    def ifc_clash(
        element_id: int,
        clearance: float = 0.0,
@@ -90,58 +84,58 @@ def build_server() -> Any:
            scope=scope,
        )

-    @_tool
+    @server.tool()
    def ifc_contexts() -> list[dict[str, Any]]:
        return session.ifc_contexts()

-    @_tool
+    @server.tool()
    def ifc_materials() -> list[dict[str, Any]]:
        return session.ifc_materials()

    # ---- Edit ----
-    @_tool
+    @server.tool()
    def ifc_list(module: str = "") -> list[dict]:
        return session.ifc_list(module=module)

-    @_tool
+    @server.tool()
    def ifc_docs(function_path: str) -> dict:
        return session.ifc_docs(function_path=function_path)

-    @_tool
+    @server.tool()
    def ifc_edit(function_path: str, params: str = "{}") -> dict:
        return session.ifc_edit(function_path=function_path, params=params)

    # ---- Extended query + edit ----
-    @_tool
+    @server.tool()
    def ifc_validate(express_rules: bool = False) -> dict[str, Any]:
        return session.ifc_validate(express_rules=express_rules)

-    @_tool
+    @server.tool()
    def ifc_schedule(max_depth: int | None = None) -> list[dict[str, Any]]:
        return session.ifc_schedule(max_depth=max_depth)

-    @_tool
+    @server.tool()
    def ifc_cost(max_depth: int | None = None) -> list[dict[str, Any]]:
        return session.ifc_cost(max_depth=max_depth)

-    @_tool
+    @server.tool()
    def ifc_schema(entity_type: str) -> dict[str, Any]:
        return session.ifc_schema(entity_type=entity_type)

-    @_tool
+    @server.tool()
    def ifc_quantify(rule: str, selector: str = "") -> dict[str, Any]:
        return session.ifc_quantify(rule=rule, selector=selector)

    # ---- Shape builder ----
-    @_tool
+    @server.tool()
    def ifc_shape_list() -> list[dict]:
        return session.ifc_shape_list()

-    @_tool
+    @server.tool()
    def ifc_shape_docs(method: str) -> dict:
        return session.ifc_shape_docs(method=method)

-    @_tool
+    @server.tool()
    def ifc_shape(method: str, params: str = "{}") -> dict:
        return session.ifc_shape(method=method, params=params)

@@ -18,9 +18,7 @@ classifiers = [
 dependencies = ["ifcopenshell", "ifcquery", "ifcedit"]

 [project.optional-dependencies]
-# Pinned <2: mcp 2.0.0 renamed mcp.server.fastmcp.FastMCP to
-# mcp.server.mcpserver.MCPServer, which this package doesn't support yet.
-mcp = ["mcp>=1.0,<2"]
+mcp = ["mcp"]

 [project.scripts]
 ifcmcp = "ifcmcp.__main__:main"
@@ -30,12 +30,6 @@ class TestServerRegistration:
        for name in expected:
            assert name in tools, f"Tool {name} not registered"

-    def test_all_tools_have_descriptions(self):
-        server = build_server()
-        tools = server._tool_manager.list_tools()
-        missing = [t.name for t in tools if not (t.description or "").strip()]
-        assert not missing, f"Tools with no description: {missing}"
-

@pytest.fixture
 def tool_fns():
@@ -60,7 +60,7 @@ operating systems. GCC (4.7 or newer) or Clang (any version) is required.

   .. code-block:: bash

-       sudo apt-get install git cmake gcc g++ libboost-all-dev libcgal-dev libeigen3-dev
+       sudo apt-get install git cmake gcc g++ libboost-all-dev libcgal-dev

   The CGAL version that ships with Ubuntu 20.04 is too old. Users on Ubuntu 20.04 are advised to manually install CGAL 5.3.

@@ -25,7 +25,7 @@ are automatically created and maintained.

 Alignments are created with stationing referents. Each layout segment is assigned a position referent that informs about
 the start point of the segment. An example is the point of curvature of a horizontal circular curve. The referent is
-nested to the segment representing the circular arc and is named with the alignment name and an indicator of the position and the station, e.g. "MyAlignment 145+98.32 (P.C.)"
+nested to the segment representing the circular arc and is named with a indicator of the position and the station, e.g. "P.C. (145+98.32)"

 This API does not determine alignment parameters based on rules, such as minimum curve radius as a function of design speed or sight distance.

@@ -79,7 +79,7 @@ from .get_layout_curve import get_layout_curve
 from .get_layout_segments import get_layout_segments
 from .get_mapped_segments import get_mapped_segments
 from .get_parent_alignment import get_parent_alignment
-from .get_stationing_nest import get_stationing_nest
+from .get_referent_nest import get_referent_nest
 from .get_vertical_layout import get_vertical_layout
 from .has_zero_length_segment import has_zero_length_segment
 from .layout_horizontal_alignment_by_pi_method import (
@@ -89,10 +89,8 @@ from .layout_vertical_alignment_by_pi_method import (
    layout_vertical_alignment_by_pi_method,
 )
 from .name_segments import name_segments
-from .update_alignment_parameter_segment_tags import update_alignment_parameter_segment_tags
 from .update_end_point import update_end_point
 from .update_fallback_position import update_fallback_position
-from .update_key_point_referents import update_key_point_referents
 from .util import *

 __all__ = [
@@ -126,16 +124,14 @@ __all__ = [
    "get_layout_curve",
    "get_layout_segments",
    "get_parent_alignment",
-    "get_stationing_nest",
+    "get_referent_nest",
    "get_vertical_layout",
    "has_zero_length_segment",
    "layout_horizontal_alignment_by_pi_method",
    "layout_vertical_alignment_by_pi_method",
    "name_segments",
    "register_referent_name_callback",
-    "update_alignment_parameter_segment_tags",
    "update_end_point",
    "update_fallback_position",
-    "update_key_point_referents",
    "get_mapped_segments",
 ]
@@ -1,30 +0,0 @@
-# IfcOpenShell - IFC toolkit and geometry engine
-# Copyright (C) 2025 Thomas Krijnen <thomas@aecgeeks.com>
-#
-# This file is part of IfcOpenShell.
-#
-# IfcOpenShell is free software: you can redistribute it and/or modify
-# it under the terms of the GNU Lesser General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# IfcOpenShell is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License
-# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
-
-import ifcopenshell
-import ifcopenshell.util.alignment
-
-
-def _get_key_point_tag(file: ifcopenshell.file, label: str, station: float) -> str:
-    """
-    Builds the station-and-label text shared by update_alignment_parameter_segment_tags (used
-    directly as IfcAlignmentParameterSegment.StartTag/EndTag) and update_key_point_referents (used,
-    prefixed with the alignment name, as IfcReferent.Name): "<station> (<label>)", e.g.
-    "145+98.32 (P.O.B.)".
-    """
-    return f"{ifcopenshell.util.alignment.station_as_string(file, station)} ({label})"
@@ -26,10 +26,9 @@ _cant_callback = None

 def register_referent_name_callback(horizontal=None, vertical=None, cant=None):
    """
-    Referents are created at the start of each horizontal, vertical, and cant segment by
-    ifcopenshell.api.alignment.update_key_point_referents. The referents represent key points in the
-    alignment layout such as Point of Curvature, Point of Tangent, and others. Different
-    juristicions use different naming systems for these key points.
+    Referents are automatically created at the start of each horizontal, vertical, and cant segment.
+    The referents represent key points in the alignment layout such as Point of Curvature, Point of Tangent, and others.
+    Different juristicions use different naming systems for these key points.

    The referent name callback functions provide a customizable method for naming these referents. If a callback is registered,
    it is called when creating the referent name, otherwise the default naming is used.
@@ -40,8 +39,8 @@ def register_referent_name_callback(horizontal=None, vertical=None, cant=None):

    The callback function returns a string that is used in the referent name for the referent at the start of `segment`.
    The callback must accomodate the following cases:
-    * prev_segment = None and segment != None - this indicates the first segment so the "Beginning of Alignment" name is returned
-    * prev_segment != None and segment == None - this indicates the last segment so the "End of Alignment" name is returned
+    * prev_segment = None and segment != None - this indicates the last segment so the "End of Alignment" name is returned
+    * prev_segment != None and segment == None - this indicates the first segment so the "Beginning of Alignment" name is returned
    * prev_segment != None and segment != None - this indicates an intermediate segment so a name representitive of the transition is returned

    Setting any or all of the callbacks to None causes the default naming to be used.
@@ -1,27 +0,0 @@
-# IfcOpenShell - IFC toolkit and geometry engine
-# Copyright (C) 2025 Thomas Krijnen <thomas@aecgeeks.com>
-#
-# This file is part of IfcOpenShell.
-#
-# IfcOpenShell is free software: you can redistribute it and/or modify
-# it under the terms of the GNU Lesser General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# IfcOpenShell is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License
-# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
-
-from typing import Callable
-
-from ifcopenshell import entity_instance
-
-
-def _sort_nest(nest: entity_instance, key: Callable) -> entity_instance:
-    """Sorts the RelatedObjects of an IfcRelNests in place, by an arbitrary key function."""
-    nest.RelatedObjects = sorted(nest.RelatedObjects, key=key)
-    return nest
@@ -20,7 +20,6 @@ from typing import Optional

 import ifcopenshell
 import ifcopenshell.api.alignment
-from ifcopenshell.api.alignment._sort_nest import _sort_nest
 from ifcopenshell.api.alignment.update_fallback_position import update_fallback_position
 import ifcopenshell.api.pset
 import ifcopenshell.guid
@@ -115,7 +114,7 @@ def add_stationing_referent(
    pset_stationing = ifcopenshell.api.pset.add_pset(file, product=referent, name="Pset_Stationing")
    ifcopenshell.api.pset.edit_pset(file, pset=pset_stationing, properties=properties)

-    nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
+    nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
    if nest is None:
        nest = file.createIfcRelNests(
            GlobalId=ifcopenshell.guid.new(), RelatingObject=alignment, RelatedObjects=(referent,)
@@ -123,6 +122,8 @@ def add_stationing_referent(
    else:
        nest.RelatedObjects += (referent,)

-    _sort_nest(nest, key=lambda x: ifcopenshell.util.element.get_pset(x, name="Pset_Stationing", prop="Station"))
+    nest.RelatedObjects = sorted(
+        nest.RelatedObjects, key=lambda x: ifcopenshell.util.element.get_pset(x, name="Pset_Stationing", prop="Station")
+    )

    return referent
@@ -64,22 +64,22 @@ def create_representation(

    # if the alignment is created without geometry it's stationing referent isn't related to the alignment geometry.
    # the stationing referent needs to be updated to have an IfcLinearPlacement that references the basis curve geometry
-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
    if (
-        stationing_nest
-        and 0 < len(stationing_nest.RelatedObjects)
-        and stationing_nest.RelatedObjects[0].ObjectPlacement
-        and not stationing_nest.RelatedObjects[0].ObjectPlacement.is_a("IfcLinearPlacement")
+        referent_nest
+        and 0 < len(referent_nest.RelatedObjects)
+        and referent_nest.RelatedObjects[0].ObjectPlacement
+        and not referent_nest.RelatedObjects[0].ObjectPlacement.is_a("IfcLinearPlacement")
    ):
        basis_curve = ifcopenshell.api.alignment.get_basis_curve(alignment)

-        if stationing_nest.RelatedObjects[0].ObjectPlacement:
-            if stationing_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.Location:
-                file.remove(stationing_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.Location)
-            if stationing_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.RefDirection:
-                file.remove(stationing_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.RefDirection)
-            file.remove(stationing_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement)
-            file.remove(stationing_nest.RelatedObjects[0].ObjectPlacement)
+        if referent_nest.RelatedObjects[0].ObjectPlacement:
+            if referent_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.Location:
+                file.remove(referent_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.Location)
+            if referent_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.RefDirection:
+                file.remove(referent_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement.RefDirection)
+            file.remove(referent_nest.RelatedObjects[0].ObjectPlacement.RelativePlacement)
+            file.remove(referent_nest.RelatedObjects[0].ObjectPlacement)

        lp = file.createIfcLinearPlacement(
            RelativePlacement=file.createIfcAxis2PlacementLinear(
@@ -93,4 +93,4 @@ def create_representation(
            )
        )
        update_fallback_position(file, lp)
-        stationing_nest.RelatedObjects[0].ObjectPlacement = lp
+        referent_nest.RelatedObjects[0].ObjectPlacement = lp
@@ -67,8 +67,8 @@ def distance_along_from_station(file: ifcopenshell.file, alignment: entity_insta
        print(dist_along) # 100.00
    """

-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
-    if stationing_nest is None:
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
+    if referent_nest is None:
        start_station = ifcopenshell.api.alignment.get_alignment_start_station(file, alignment)
        return station - start_station

@@ -77,7 +77,7 @@ def distance_along_from_station(file: ifcopenshell.file, alignment: entity_insta
            _distance_along_of_referent(referent),
            ifcopenshell.util.element.get_pset(referent, name="Pset_Stationing", prop="Station"),
        )
-        for referent in stationing_nest.RelatedObjects
+        for referent in referent_nest.RelatedObjects
    ]
    stations.sort(key=lambda entry: entry[0])

@@ -20,18 +20,12 @@ import ifcopenshell
 from ifcopenshell import entity_instance


-def get_stationing_nest(file: ifcopenshell.file, alignment: entity_instance) -> entity_instance:
+def get_referent_nest(file: ifcopenshell.file, alignment: entity_instance) -> entity_instance:
    """
-    Searches for the IfcRelNests that defines the alignment's stationing scheme.
-
-    The returned nest is nested to the IfcAlignment and its RelatedObjects contains only the
-    IfcReferent(s) (PredefinedType="STATION") that establish the alignment's starting station and
-    any station equations along it, as created by add_stationing_referent. It does not contain any
-    other kind of referent (e.g. key-point referents from update_key_point_referents live in their
-    own, separate IfcRelNests).
+    Searches for the IfcRelNest that contains IfcReferent.

    :param file:
-    :param alignment: The IfcAlignment which hosts the stationing IfcReferent(s)
+    :param alignment: The IfcAlignment which hosts IfcReferent
    :return: Returns the IfcRelNests or None
    """
    if not alignment.is_a("IfcAlignment"):
@@ -1,108 +0,0 @@
-# IfcOpenShell - IFC toolkit and geometry engine
-# Copyright (C) 2025 Thomas Krijnen <thomas@aecgeeks.com>
-#
-# This file is part of IfcOpenShell.
-#
-# IfcOpenShell is free software: you can redistribute it and/or modify
-# it under the terms of the GNU Lesser General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# IfcOpenShell is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License
-# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
-
-import ifcopenshell
-import ifcopenshell.api.alignment
-from ifcopenshell import entity_instance
-from ifcopenshell.api.alignment._get_key_point_tag import _get_key_point_tag
-from ifcopenshell.api.alignment._get_segment_start_point_label import (
-    _get_segment_start_point_label,
-)
-
-
-def update_alignment_parameter_segment_tags(
-    file: ifcopenshell.file, layout: entity_instance, label_end_tag: bool = False
-) -> None:
-    """
-    Sets IfcAlignmentParameterSegment.StartTag (and, optionally, EndTag) for every segment
-    transition in an alignment layout. Unlike update_key_point_referents, this does not create any
-    IfcReferent or IfcRelNests -- it only mutates the StartTag/EndTag string attributes already
-    present on each segment's DesignParameters.
-
-    Every real segment's StartTag is set to a computed tag describing the point where it begins,
-    using the same label-and-station format as update_key_point_referents' Name minus the alignment
-    name (via _get_key_point_tag), e.g. "145+98.32 (P.C.)". The first segment's StartTag comes from
-    the "Beginning of Alignment" boundary label.
-
-    EndTag is left untouched unless `label_end_tag` is True. When enabled, for each transition
-    between two consecutive segments, the outgoing segment's EndTag is set to the same tag as the
-    incoming segment's StartTag (they describe the same physical point), and the last segment's
-    EndTag is set from the "End of Alignment" boundary label.
-
-    Labels come from _get_segment_start_point_label -- if a callback has been registered via
-    register_referent_name_callback(), its output is used instead of the built-in labels, exactly as
-    in update_key_point_referents.
-
-    :param layout: IfcAlignmentHorizontal, IfcAlignmentVertical, or IfcAlignmentCant
-    :param label_end_tag: if True, also sets EndTag on every real segment. If False (default),
-        EndTag is left untouched.
-    :return: None -- this function mutates segment.DesignParameters.StartTag/EndTag in place
-
-    Example:
-
-    .. code:: python
-
-        horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-        ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(model, horizontal)
-    """
-
-    expected_types = ["IfcAlignmentHorizontal", "IfcAlignmentVertical", "IfcAlignmentCant"]
-    if not layout.is_a() in expected_types:
-        raise TypeError(
-            f"Expected entity type to be one of {[_ for _ in expected_types]}, instead received {layout.is_a()}"
-        )
-
-    alignment = ifcopenshell.api.alignment.get_alignment(layout)
-    if alignment is None:
-        raise ValueError(f"{layout.is_a()} #{layout.id()} is not nested under an IfcAlignment.")
-
-    segments = list(ifcopenshell.api.alignment.get_layout_segments(layout))
-    if segments and ifcopenshell.api.alignment.has_zero_length_segment(layout):
-        segments = segments[:-1]
-
-    if not segments:
-        return
-
-    start_station = ifcopenshell.api.alignment.get_alignment_start_station(file, alignment)
-    is_horizontal = layout.is_a("IfcAlignmentHorizontal")
-
-    distance_along = 0.0
-    prev_segment = None
-    for segment in segments:
-        dp = segment.DesignParameters
-        seg_distance_along = distance_along if is_horizontal else dp.StartDistAlong
-
-        label = _get_segment_start_point_label(prev_segment, segment)
-        station = start_station + seg_distance_along
-        tag = _get_key_point_tag(file, label, station)
-
-        dp.StartTag = tag
-        if prev_segment is not None and label_end_tag:
-            prev_segment.DesignParameters.EndTag = tag
-
-        if is_horizontal:
-            distance_along += dp.SegmentLength
-        else:
-            distance_along = dp.StartDistAlong + dp.HorizontalLength
-
-        prev_segment = segment
-
-    if label_end_tag:
-        label = _get_segment_start_point_label(prev_segment, None)
-        station = start_station + distance_along
-        prev_segment.DesignParameters.EndTag = _get_key_point_tag(file, label, station)
@@ -1,217 +0,0 @@
-# IfcOpenShell - IFC toolkit and geometry engine
-# Copyright (C) 2025 Thomas Krijnen <thomas@aecgeeks.com>
-#
-# This file is part of IfcOpenShell.
-#
-# IfcOpenShell is free software: you can redistribute it and/or modify
-# it under the terms of the GNU Lesser General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# IfcOpenShell is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License
-# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
-
-from typing import Optional
-
-import ifcopenshell
-import ifcopenshell.api.alignment
-import ifcopenshell.api.pset
-import ifcopenshell.guid
-import ifcopenshell.util.element
-from ifcopenshell import entity_instance
-from ifcopenshell.api.alignment._get_key_point_tag import _get_key_point_tag
-from ifcopenshell.api.alignment._get_segment_start_point_label import (
-    _get_segment_start_point_label,
-)
-from ifcopenshell.api.alignment._sort_nest import _sort_nest
-from ifcopenshell.api.alignment.update_fallback_position import update_fallback_position
-
-
-def _remove_referent(file: ifcopenshell.file, referent: entity_instance) -> None:
-    """Cleanly deletes a key-point IfcReferent: its Pset_Stationing, its ObjectPlacement (if
-    exclusively owned by it), and finally the referent itself."""
-    for inverse in list(file.get_inverse(referent)):
-        if inverse.is_a("IfcRelDefinesByProperties"):
-            ifcopenshell.api.pset.remove_pset(file, product=referent, pset=inverse.RelatingPropertyDefinition)
-
-    object_placement = referent.ObjectPlacement
-    if object_placement and file.get_total_inverses(object_placement) == 1:
-        referent.ObjectPlacement = None
-        ifcopenshell.util.element.remove_deep2(file, object_placement)
-
-    file.remove(referent)  # also strips referent out of any IfcRelNests.RelatedObjects referencing it
-
-
-def _create_key_point_referent(
-    file: ifcopenshell.file,
-    alignment: entity_instance,
-    curve: Optional[entity_instance],
-    label: str,
-    distance_along: float,
-    station: float,
-) -> entity_instance:
-    if curve and curve.is_a("IfcCompositeCurve") and 0 < len(curve.Segments):
-        object_placement = file.createIfcLinearPlacement(
-            RelativePlacement=file.createIfcAxis2PlacementLinear(
-                Location=file.createIfcPointByDistanceExpression(
-                    DistanceAlong=file.createIfcLengthMeasure(distance_along),
-                    OffsetLateral=None,
-                    OffsetVertical=None,
-                    OffsetLongitudinal=None,
-                    BasisCurve=curve,
-                )
-            ),
-        )
-        update_fallback_position(file, object_placement)
-    else:
-        object_placement = file.createIfcLocalPlacement(
-            PlacementRelTo=None,
-            RelativePlacement=file.createIfcAxis2Placement2D(
-                Location=file.createIfcCartesianPoint(alignment.ObjectPlacement.RelativePlacement.Location.Coordinates)
-            ),
-        )
-
-    name = f"{alignment.Name} {_get_key_point_tag(file, label, station)}"
-
-    referent = file.createIfcReferent(
-        GlobalId=ifcopenshell.guid.new(),
-        OwnerHistory=None,
-        Name=name,
-        Description=None,
-        ObjectType=None,
-        ObjectPlacement=object_placement,
-        Representation=None,
-        PredefinedType="POSITION",
-    )
-
-    pset_stationing = ifcopenshell.api.pset.add_pset(file, product=referent, name="Pset_Stationing")
-    ifcopenshell.api.pset.edit_pset(file, pset=pset_stationing, properties={"Station": station})
-
-    return referent
-
-
-def update_key_point_referents(
-    file: ifcopenshell.file,
-    layout: entity_instance,
-    rel_nests: Optional[entity_instance] = None,
-    clear: bool = False,
-) -> entity_instance:
-    """
-    Creates IfcReferent key-point markers for every segment transition in an alignment layout.
-
-    Labels are derived from _get_segment_start_point_label (e.g. "P.C.", "P.T.", "P.O.B.",
-    "P.V.C.", ...), and combined with the alignment name and station to build the Name, e.g.
-    "MyAlignment 145+98.32 (P.C.)". Different jurisdictions use
-    different naming systems for these key points -- register_referent_name_callback() lets a
-    caller override the default horizontal/vertical/cant labeling before calling this function; if
-    a callback is registered, its output is used here instead of the built-in labels. Referents are
-    nested to `rel_nests`, an IfcRelNests distinct from the layout's segment nest (found via
-    get_alignment_segment_nest) and from the alignment's stationing nest (found via
-    get_stationing_nest) -- key-point referents never belong in either of those.
-
-    :param layout: IfcAlignmentHorizontal, IfcAlignmentVertical, or IfcAlignmentCant
-    :param rel_nests: an existing IfcRelNests to (re)populate; its RelatingObject must be the
-        IfcAlignment that nests `layout` (TypeError is raised otherwise). If omitted, a new
-        IfcRelNests is always created and related to that IfcAlignment -- there is no implicit
-        search for or reuse of a previously created nest. Callers who want to regenerate into an
-        existing nest must pass it back in explicitly via `rel_nests`.
-    :param clear: if True, deletes all IfcReferent currently in rel_nests.RelatedObjects (and their
-        Pset_Stationing) before regenerating. If False (default), new referents are appended to
-        whatever already exists -- no deduplication.
-    :return: the IfcRelNests, with RelatedObjects sorted ascending by Pset_Stationing.Station
-
-    Example:
-
-    .. code:: python
-
-        horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-        nest = ifcopenshell.api.alignment.update_key_point_referents(model, horizontal)
-
-    Example, with custom labels for a jurisdiction that doesn't use the built-in abbreviations:
-
-    .. code:: python
-
-        def my_horizontal_labels(prev_segment, segment):
-            if prev_segment is None:
-                return "Start"
-            if segment is None:
-                return "End"
-            return "Curve Point"  # a name representative of the prev_segment -> segment transition
-
-        ifcopenshell.api.alignment.register_referent_name_callback(horizontal=my_horizontal_labels)
-        horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-        nest = ifcopenshell.api.alignment.update_key_point_referents(model, horizontal)
-        # nest.RelatedObjects[0].Name ends with "(Start)" instead of the default "(P.O.B.)"
-    """
-
-    expected_types = ["IfcAlignmentHorizontal", "IfcAlignmentVertical", "IfcAlignmentCant"]
-    if not layout.is_a() in expected_types:
-        raise TypeError(
-            f"Expected entity type to be one of {[_ for _ in expected_types]}, instead received {layout.is_a()}"
-        )
-
-    alignment = ifcopenshell.api.alignment.get_alignment(layout)
-    if alignment is None:
-        raise ValueError(f"{layout.is_a()} #{layout.id()} is not nested under an IfcAlignment.")
-
-    if rel_nests is not None:
-        if not rel_nests.RelatingObject.is_a("IfcAlignment"):
-            raise TypeError(
-                f"Expected rel_nests.RelatingObject to be IfcAlignment, instead received "
-                f"{rel_nests.RelatingObject.is_a()}"
-            )
-    else:
-        rel_nests = file.createIfcRelNests(
-            GlobalId=ifcopenshell.guid.new(), RelatingObject=alignment, RelatedObjects=()
-        )
-
-    if clear:
-        for referent in list(rel_nests.RelatedObjects):
-            _remove_referent(file, referent)
-        rel_nests.RelatedObjects = ()
-
-    segments = list(ifcopenshell.api.alignment.get_layout_segments(layout))
-    if segments and ifcopenshell.api.alignment.has_zero_length_segment(layout):
-        segments = segments[:-1]
-
-    if not segments:
-        _sort_nest(
-            rel_nests, key=lambda x: ifcopenshell.util.element.get_pset(x, name="Pset_Stationing", prop="Station")
-        )
-        return rel_nests
-
-    start_station = ifcopenshell.api.alignment.get_alignment_start_station(file, alignment)
-    curve = ifcopenshell.api.alignment.get_layout_curve(layout)
-    is_horizontal = layout.is_a("IfcAlignmentHorizontal")
-
-    new_referents = []
-    distance_along = 0.0
-    prev_segment = None
-    for segment in segments:
-        dp = segment.DesignParameters
-        seg_distance_along = distance_along if is_horizontal else dp.StartDistAlong
-
-        label = _get_segment_start_point_label(prev_segment, segment)
-        station = start_station + seg_distance_along
-        new_referents.append(_create_key_point_referent(file, alignment, curve, label, seg_distance_along, station))
-
-        if is_horizontal:
-            distance_along += dp.SegmentLength
-        else:
-            distance_along = dp.StartDistAlong + dp.HorizontalLength
-
-        prev_segment = segment
-
-    label = _get_segment_start_point_label(prev_segment, None)
-    station = start_station + distance_along
-    new_referents.append(_create_key_point_referent(file, alignment, curve, label, distance_along, station))
-
-    rel_nests.RelatedObjects = tuple(rel_nests.RelatedObjects) + tuple(new_referents)
-    _sort_nest(rel_nests, key=lambda x: ifcopenshell.util.element.get_pset(x, name="Pset_Stationing", prop="Station"))
-
-    return rel_nests
@@ -23,10 +23,6 @@ import ifcopenshell
 import ifcopenshell.util.element
 import ifcopenshell.util.pset

-# Sentinel distinguishing "no Unit dict was passed at all" from "a Unit dict was passed
-# with Unit explicitly set to None" (i.e. explicitly clear an existing override).
-_NO_UNIT = object()
-

 def edit_pset(
    file: ifcopenshell.file,
@@ -289,7 +285,7 @@ class Usecase:
                f'Value "{self.settings["properties"][prop.Name]}" is not a valid value for enum property {prop.Name}.'
            )

-        if unit is not _NO_UNIT:
+        if unit:
            prop.Unit = unit
        del self.settings["properties"][prop.Name]
        return prop
@@ -314,7 +310,7 @@ class Usecase:
            )
            value = self.cast_value_to_primary_measure_type(value, primary_measure_type)
            prop.NominalValue = self.file.create_entity(primary_measure_type, value)
-        if unit is not _NO_UNIT:
+        if unit:
            prop.Unit = unit
        del self.settings["properties"][prop.Name]
        return prop
@@ -333,7 +329,7 @@ class Usecase:
                # If it's not an entity, then it's a primitive data type
                elif not value.is_entity():
                    kwargs = {"Name": name, "NominalValue": value}
-                    if unit is not None and unit is not _NO_UNIT:
+                    if unit:
                        kwargs["Unit"] = unit
                    properties.append(self.file.create_entity("IfcPropertySingleValue", **kwargs))

@@ -357,7 +353,7 @@ class Usecase:
                                "IfcPropertyListValue",
                                Name=name,
                                ListValues=[self.file.create_entity(ifc_class, v) for v in value],
-                                Unit=unit if (unit is not None and unit is not _NO_UNIT) else None,
+                                Unit=unit,
                            )
                        )
                        break
@@ -367,7 +363,7 @@ class Usecase:
                            "IFCPROPERTYENUMERATION",
                            Name=name,
                            EnumerationValues=pset_template.Enumerators.EnumerationValues,
-                            **({"Unit": unit} if (unit is not None and unit is not _NO_UNIT) else {}),
+                            **({"Unit": unit} if unit else {}),
                        )
                        prop_enum_value = self.file.create_entity(
                            "IFCPROPERTYENUMERATEDVALUE",
@@ -393,7 +389,7 @@ class Usecase:
                    value = self.cast_value_to_primary_measure_type(value, primary_measure_type)
                    nominal_value = self.file.create_entity(primary_measure_type, value)
                args = {"Name": name, "NominalValue": nominal_value}
-                if unit is not None and unit is not _NO_UNIT:
+                if unit:
                    args["Unit"] = unit

                properties.append(self.file.create_entity("IfcPropertySingleValue", **args))
@@ -483,16 +479,12 @@ class Usecase:
    def unpack_unit_value(value_candidate):
        """
        Returns tuple of the format: (Unit, NominalValue)
-
-        NOTE: Unit is the module-level _NO_UNIT sentinel when no Unit was specified at all
-        (bare value, or a dict without a "Unit" key), so that callers can distinguish "leave
-        the existing Unit untouched" from an explicit `{"Unit": None, ...}` (clear the
-        existing Unit override, falling back to the project default).
+        NOTE: Unit fallbacks to None
        """
        if value_candidate is None:
            return (None, None)

        if isinstance(value_candidate, dict):  # Custom IfcUnits can be passed in a dict along with the pset value
-            return (value_candidate.get("Unit", _NO_UNIT), value_candidate["NominalValue"])
+            return (value_candidate["Unit"], value_candidate["NominalValue"])

-        return (_NO_UNIT, value_candidate)
+        return (None, value_candidate)
@@ -136,32 +136,10 @@ def edit_qto(
    return usecase.execute()


-# Sentinel distinguishing "no Unit dict was passed at all" from "a Unit dict was passed
-# with Unit explicitly set to None" (i.e. explicitly clear an existing override).
-_NO_UNIT = object()
-
-
 class Usecase:
    file: ifcopenshell.file
    settings: dict[str, Any]

-    @staticmethod
-    def unpack_unit_value(value_candidate):
-        """
-        Returns tuple of the format: (Unit, NominalValue)
-
-        NOTE: a dict value_candidate is ambiguous with the IfcPhysicalComplexQuantity spec
-        convention ({"Discrimination": ..., "HasQuantities": ...}) used elsewhere in this
-        module -- callers must check for that case (absence of a "Unit" key) before calling
-        this. Unit is the module-level _NO_UNIT sentinel when no Unit was specified at all
-        (bare value, or a dict without a "Unit" key), so that callers can distinguish "leave
-        the existing Unit untouched" from an explicit `{"Unit": None, ...}` (clear the
-        existing Unit override, falling back to the project default).
-        """
-        if isinstance(value_candidate, dict) and "Unit" in value_candidate:
-            return (value_candidate["Unit"], value_candidate["NominalValue"])
-        return (_NO_UNIT, value_candidate)
-
    def execute(self):
        self.qto_idx = 5
        if self.settings["qto"].is_a("IfcPhysicalComplexQuantity"):
@@ -195,19 +173,16 @@ class Usecase:
        name = prop.Name
        if value is None:
            self.file.remove(prop)
-        elif prop.is_a("IfcPhysicalComplexQuantity") and isinstance(value, dict) and "Unit" not in value:
+        elif prop.is_a("IfcPhysicalComplexQuantity") and isinstance(value, dict):
            prop.Discrimination = value.get("Discrimination", prop.Discrimination)
            ifcopenshell.api.pset.edit_qto(self.file, qto=prop, properties=value["HasQuantities"])
        elif prop.is_a("IfcPhysicalSimpleQuantity"):
-            unit, value = self.unpack_unit_value(value)
            value = value.wrappedValue if isinstance(value, ifcopenshell.entity_instance) else value
            # 3 IfcPhysicalSimpleQuantity.XXXValue
            if self.file.schema == "IFC4X3" and prop.is_a("IfcQuantityCount"):
                prop[3] = int(value)
            else:
                prop[3] = float(value)
-            if unit is not _NO_UNIT:
-                prop.Unit = unit
        del self.settings["properties"][name]

    def add_new_properties(self) -> list[ifcopenshell.entity_instance]:
@@ -215,20 +190,21 @@ class Usecase:
        for name, value in self.settings["properties"].items():
            if value is None:
                continue
-            if isinstance(value, dict) and "Unit" not in value:
+            if isinstance(value, dict):
                complex_qto = self.file.create_entity(
                    "IfcPhysicalComplexQuantity", Name=name, Discrimination=value["Discrimination"]
                )
                properties.append(complex_qto)
                ifcopenshell.api.pset.edit_qto(self.file, qto=complex_qto, properties=value["HasQuantities"])
            else:
-                unit, value = self.unpack_unit_value(value)
                property_type = self.get_canonical_property_type(name, value)
                value = value.wrappedValue if isinstance(value, ifcopenshell.entity_instance) else value
-                kwargs = {"Name": name, "{}Value".format(property_type): value}
-                if unit is not None and unit is not _NO_UNIT:
-                    kwargs["Unit"] = unit
-                properties.append(self.file.create_entity("IfcQuantity{}".format(property_type), **kwargs))
+                properties.append(
+                    self.file.create_entity(
+                        "IfcQuantity{}".format(property_type),
+                        **{"Name": name, "{}Value".format(property_type): value},
+                    )
+                )
        return properties

    def extend_qto_with_new_properties(self, new_properties: list[ifcopenshell.entity_instance]) -> None:
@@ -64,10 +64,7 @@ DEFAULTS = {
    "project_globalid": lambda d: compress(uuid.uuid4().hex),
    "schema_identifier": lambda d: "IFC4",
    "timestamp": lambda d: int(time.time()),
-    "timestring": lambda d: time.strftime(
-        "%Y-%m-%dT%H:%M:%S",
-        time.gmtime(d["timestamp"] if d.get("timestamp") is not None else time.time()),
-    ),
+    "timestring": lambda d: time.strftime("%Y-%m-%dT%H:%M:%S", time.gmtime(d.get("timestamp") or time.time())),
    "mvd": lambda d: (
        "ReferenceView_V1.2"
        if d.get("schema_identifier") == "IFC4"
@@ -406,51 +406,6 @@ def get_named_dimensions(name):
    return named_dimensions.get(name, (0, 0, 0, 0, 0, 0, 0))


-def get_unit_dimensions(unit: ifcopenshell.entity_instance) -> tuple[int, int, int, int, int, int, int]:
-    """Get the dimensional exponents of a unit, per IfcDimensionalExponents.
-
-    Supports IfcSIUnit, IfcConversionBasedUnit, IfcContextDependentUnit, and
-    IfcDerivedUnit (composed recursively from its elements).
-
-    :param unit: The unit to inspect.
-    :return: A 7-tuple of (Length, Mass, Time, ElectricCurrent,
-        ThermodynamicTemperature, AmountOfSubstance, LuminousIntensity).
-    """
-    if unit.is_a("IfcDerivedUnit"):
-        dimensions = [0, 0, 0, 0, 0, 0, 0]
-        for element in unit.Elements:
-            element_dimensions = get_unit_dimensions(element.Unit)
-            for i in range(7):
-                dimensions[i] += element_dimensions[i] * element.Exponent
-        return tuple(dimensions)
-    if unit.is_a("IfcSIUnit"):
-        return get_si_dimensions(unit.Name.replace("METER", "METRE"))
-    return get_named_dimensions(getattr(unit, "UnitType", None))
-
-
-def identify_unit_dimensions(unit: ifcopenshell.entity_instance) -> Union[str, None]:
-    """Identify which named IfcUnitEnum type a unit's dimensions correspond to.
-
-    This is mainly useful for an IfcDerivedUnit that has no named
-    IfcDerivedUnitEnum match for its measure type, allowing it to still be
-    recognised as, e.g., a pressure unit by dimensional analysis alone.
-
-    Note that dimensionless quantities (e.g. plane angle, solid angle, or a
-    genuinely unitless value) are dimensionally indistinguishable, so this
-    heuristically returns the first zero-dimension match rather than
-    disambiguating them.
-
-    :param unit: The unit to identify.
-    :return: An uppercase IfcUnitEnum value, or None if no named type shares
-        the same dimensions.
-    """
-    dimensions = get_unit_dimensions(unit)
-    for name, named in named_dimensions.items():
-        if named == dimensions:
-            return name
-    return None
-
-
 def get_unit_assignment(ifc_file: ifcopenshell.file) -> Union[ifcopenshell.entity_instance, None]:
    return ifc_file.by_type("IfcProject")[0].UnitsInContext

@@ -466,16 +421,7 @@ def cache_units(ifc_file: ifcopenshell.file) -> None:
    """
    ifc_file.units = {}
    if assignment := get_unit_assignment(ifc_file):
-        all_units = assignment.Units or []
-        units = {u.UnitType: u for u in all_units if getattr(u, "UnitType", None)}
-        # As in get_project_unit(): a literal match always wins; an IfcDerivedUnit with no
-        # literal UnitType match is matched dimensionally instead, only to fill a gap.
-        for unit in all_units:
-            if unit.is_a("IfcDerivedUnit"):
-                dimension = identify_unit_dimensions(unit)
-                if dimension and dimension not in units:
-                    units[dimension] = unit
-        ifc_file.units = units
+        ifc_file.units = {u.UnitType: u for u in assignment.Units if getattr(u, "UnitType", None)}


 def clear_unit_cache(ifc_file: ifcopenshell.file) -> None:
@@ -491,10 +437,6 @@ def get_project_unit(
 ) -> Union[ifcopenshell.entity_instance, None]:
    """Get the default project unit of a particular unit type

-    IfcDerivedUnit is matched first by a literal `UnitType` match, then, as a fallback, by
-    dimensional analysis (:func:`identify_unit_dimensions`), mirroring
-    :func:`get_candidate_units`.
-
    :param ifc_file: The IFC file.
    :param unit_type: The type of unit, taken from the list of IFC unit types,
        such as "LENGTHUNIT".
@@ -506,39 +448,9 @@ def get_project_unit(
    if units := ifc_file.units:
        return units.get(unit_type, None)
    if unit_assignment := get_unit_assignment(ifc_file):
-        dimensional_match = None
        for unit in unit_assignment.Units or []:
            if getattr(unit, "UnitType", None) == unit_type:
                return unit
-            if dimensional_match is None and unit.is_a("IfcDerivedUnit") and identify_unit_dimensions(unit) == unit_type:
-                dimensional_match = unit
-        return dimensional_match
-
-
-def get_candidate_units(ifc_file: ifcopenshell.file, unit_type: str) -> list[ifcopenshell.entity_instance]:
-    """Get all units in the file usable as an override for `unit_type`.
-
-    Unlike :func:`get_project_unit`, this returns every matching unit defined
-    in the file (e.g. both an mm and an m IfcSIUnit might be present), not
-    just the one currently assigned as the project default.
-
-    IfcDerivedUnit is matched first by a literal `UnitType` match, then, as a
-    fallback, by dimensional analysis (:func:`identify_unit_dimensions`) --
-    that fallback only helps for the dimension families covered by
-    `named_dimensions` (the core `IfcUnitEnum` types); it won't match e.g.
-    `"MODULUSOFELASTICITYUNIT"` by dimension alone, only by literal `UnitType`.
-
-    :param ifc_file: The IFC file.
-    :param unit_type: The type of unit, taken from the list of IFC unit
-        types, such as "LENGTHUNIT", or an IfcDerivedUnitEnum value such as
-        "MODULUSOFELASTICITYUNIT".
-    :return: All matching IfcNamedUnit / IfcDerivedUnit entities in the file.
-    """
-    candidates = [u for u in ifc_file.by_type("IfcNamedUnit") if getattr(u, "UnitType", None) == unit_type]
-    for unit in ifc_file.by_type("IfcDerivedUnit"):
-        if getattr(unit, "UnitType", None) == unit_type or identify_unit_dimensions(unit) == unit_type:
-            candidates.append(unit)
-    return candidates


 def get_property_unit(
@@ -568,8 +480,7 @@ def get_property_unit(
        entity = prop.wrapped_data.declaration().as_entity()
        measure_class = entity.attribute_by_index(3).type_of_attribute().declared_type().name()
    elif prop.is_a("IfcPropertySingleValue"):
-        if value := prop.NominalValue:
-            measure_class = value.is_a()
+        measure_class = prop.NominalValue.is_a()
    elif prop.is_a("IfcPropertyEnumeratedValue"):
        if prop.EnumerationReference:
            if unit := prop.EnumerationReference.Unit:
@@ -711,8 +622,6 @@ def get_symbol_quantity_class(symbol: Optional[str] = None) -> QUANTITY_CLASS:


 def get_unit_symbol(unit: ifcopenshell.entity_instance) -> str:
-    if unit.is_a("IfcDerivedUnit"):
-        return get_derived_unit_symbol(unit)
    symbol: str = ""
    if unit.is_a("IfcSIUnit"):
        symbol += prefix_symbols.get(unit.Prefix, "")
@@ -722,28 +631,6 @@ def get_unit_symbol(unit: ifcopenshell.entity_instance) -> str:
    return symbol


-def get_derived_unit_symbol(unit: ifcopenshell.entity_instance) -> str:
-    """Compose a unit symbol for an IfcDerivedUnit from its elements.
-
-    E.g. a derived unit of NEWTON / SQUARE_METRE composes to "N/m2".
-
-    :param unit: The IfcDerivedUnit.
-    :return: The composed symbol.
-    """
-    numerator = []
-    denominator = []
-    for element in unit.Elements:
-        symbol = get_unit_symbol(element.Unit)
-        exponent = abs(element.Exponent)
-        if exponent != 1:
-            symbol += str(exponent)
-        (numerator if element.Exponent > 0 else denominator).append(symbol)
-    result = ".".join(numerator) or "1"
-    if denominator:
-        result += "/" + ".".join(denominator)
-    return result
-
-
 def convert_unit(value: float, from_unit: ifcopenshell.entity_instance, to_unit: ifcopenshell.entity_instance) -> float:
    """Convert from one unit to another unit

@@ -797,70 +684,6 @@ def convert(value: float, from_prefix: Optional[str], from_unit: str, to_prefix:
    return value


-def get_named_unit_scale(unit: ifcopenshell.entity_instance) -> float:
-    """Get the scale factor to convert a value in a named unit to SI units.
-
-    Supports IfcSIUnit and IfcConversionBasedUnit (including chains of
-    conversion-based units). Does not support IfcDerivedUnit -- see
-    :func:`get_derived_unit_scale` for that.
-
-    :param unit: The IfcNamedUnit.
-    :returns: The scale factor.
-    """
-    scale = 1.0
-    while unit.is_a("IfcConversionBasedUnit"):
-        conversion_factor = unit.ConversionFactor
-        scale *= conversion_factor.ValueComponent.wrappedValue
-        unit = conversion_factor.UnitComponent
-    if unit.is_a("IfcSIUnit"):
-        prefix_multiplier = get_prefix_multiplier(unit.Prefix)
-        # An SI prefix attaches to the base unit symbol, and the prefixed
-        # symbol is raised to the power as a whole: dm3 = (dm)3 = 1e-3 m3,
-        # not 0.1 m3. For units whose dimensions are a pure power of length
-        # (METRE, SQUARE_METRE, CUBIC_METRE) the prefix multiplier must
-        # therefore be raised to the length exponent. Units with mixed or
-        # non-length dimensions (PASCAL, NEWTON, GRAM, ...) keep the linear
-        # multiplier, as there the prefix scales the derived unit itself.
-        # https://github.com/IfcOpenShell/IfcOpenShell/issues/9278
-        #
-        # Dimensions is looked up from si_dimensions by name rather than via
-        # unit.Dimensions (the schema-derived IfcDimensionalExponents), since
-        # the derived attribute isn't computed for SQLite-linked files and
-        # would return None there.
-        length_exponent, *other_exponents = get_si_dimensions(unit.Name.replace("METER", "METRE"))
-        if length_exponent > 0 and not any(other_exponents):
-            prefix_multiplier **= length_exponent
-        scale *= prefix_multiplier
-    return scale
-
-
-def get_derived_unit_scale(unit: ifcopenshell.entity_instance) -> float:
-    """Get the scale factor to convert a value in an IfcDerivedUnit to SI units.
-
-    :param unit: The IfcDerivedUnit.
-    :returns: The scale factor.
-    """
-    scale = 1.0
-    for element in unit.Elements:
-        scale *= get_named_unit_scale(element.Unit) ** element.Exponent
-    return scale
-
-
-def get_unit_scale(unit: ifcopenshell.entity_instance) -> float:
-    """Get the scale factor to convert a value in `unit` to SI units.
-
-    Dispatches to :func:`get_derived_unit_scale` for IfcDerivedUnit, or
-    :func:`get_named_unit_scale` otherwise (IfcSIUnit / IfcConversionBasedUnit,
-    including chains).
-
-    :param unit: The unit to get the scale factor for.
-    :returns: The scale factor.
-    """
-    if unit.is_a("IfcDerivedUnit"):
-        return get_derived_unit_scale(unit)
-    return get_named_unit_scale(unit)
-
-
 def calculate_unit_scale(ifc_file: ifcopenshell.file, unit_type: str = "LENGTHUNIT") -> float:
    """Returns a unit scale factor to convert to and from IFC project units and SI units.

@@ -872,17 +695,17 @@ def calculate_unit_scale(ifc_file: ifcopenshell.file, unit_type: str = "LENGTHUN
        si_meters / unit_scale = ifc_project_length

    :param ifc_file: The IFC file.
-    :param unit_type: The type of SI unit, defaults to "LENGTHUNIT". This may
-        also be an IfcDerivedUnitEnum value (e.g. "MASSDENSITYUNIT") to
-        support project units defined as an IfcDerivedUnit.
+    :param unit_type: The type of SI unit, defaults to "LENGTHUNIT"
    :returns: The scale factor
    """
-    if type(ifc_file) is ifcopenshell.file and unit_type:
-        schema = ifcopenshell.ifcopenshell_wrapper.schema_by_name(ifc_file.schema_identifier)
-        valid_types = set(schema.declaration_by_name("IfcUnitEnum").enumeration_items())
-        valid_types |= set(schema.declaration_by_name("IfcDerivedUnitEnum").enumeration_items())
-        if unit_type not in valid_types:
-            raise ValueError(f"Unit type {unit_type!r} does not name a valid type")
+    if (
+        type(ifc_file) is ifcopenshell.file
+        and unit_type
+        not in ifcopenshell.ifcopenshell_wrapper.schema_by_name(ifc_file.schema_identifier)
+        .declaration_by_name("IfcUnitEnum")
+        .enumeration_items()
+    ):
+        raise ValueError(f"Unit type {unit_type!r} does not name a valid type")

    # Currently we assume that all ifc projects must have IfcProject.
    if not (projects := ifc_file.by_type("IfcProject")) or not (units := projects[0].UnitsInContext):
@@ -892,7 +715,12 @@ def calculate_unit_scale(ifc_file: ifcopenshell.file, unit_type: str = "LENGTHUN
    for unit in units.Units:
        if getattr(unit, "UnitType", ...) != unit_type:
            continue
-        unit_scale *= get_unit_scale(unit)
+        while unit.is_a("IfcConversionBasedUnit"):
+            conversion_factor = unit.ConversionFactor
+            unit_scale *= conversion_factor.ValueComponent.wrappedValue
+            unit = conversion_factor.UnitComponent
+        if unit.is_a("IfcSIUnit"):
+            unit_scale *= get_prefix_multiplier(unit.Prefix)
    return unit_scale


@@ -39,9 +39,9 @@ def test_add_segment_to_layout():

    alignment = ifcopenshell.api.alignment.create(file, "")

-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
    assert (
-        len(stationing_nest.RelatedObjects) == 1
+        len(referent_nest.RelatedObjects) == 1
    )  # the alignment creates the stationing nest and it has one referent to defined the stationing for the alignment

    horizontal_alignment = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
@@ -75,8 +75,8 @@ def test_add_segment_to_layout():
    assert len(horizontal_alignment.IsNestedBy) == 1
    segment_nest = ifcopenshell.api.alignment.get_alignment_segment_nest(horizontal_alignment)
    assert len(segment_nest.RelatedObjects) == 2
-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
-    assert len(stationing_nest.RelatedObjects) == 1  # test this a second time to make sure that it is still true
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
+    assert len(referent_nest.RelatedObjects) == 1  # test this a second time to make sure that it is still true


 test_add_segment_to_layout()
@@ -39,8 +39,8 @@ def test_add_stationing_to_alignment():

    alignment = ifcopenshell.api.alignment.create(file, "TestAlignment", start_station=2000.0)

-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
-    referent = stationing_nest.RelatedObjects[0]
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
+    referent = referent_nest.RelatedObjects[0]

    assert referent.PredefinedType == "STATION"
    assert referent.Name == "2+000.000"
@@ -54,10 +54,10 @@ def test_add_stationing_to_alignment():
        file, "4+000.000", alignment, distance_along=1000.0, station=4000.0, incoming_station=3000.0
    )

-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
-    assert len(stationing_nest.RelatedObjects) == 2
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
+    assert len(referent_nest.RelatedObjects) == 2

-    assert second_referent == stationing_nest.RelatedObjects[1]
+    assert second_referent == referent_nest.RelatedObjects[1]

    assert second_referent.PredefinedType == "STATION"
    assert second_referent.Name == "4+000.000"
@@ -36,11 +36,11 @@ def test_add_vertical_alignment():
    layout_nest = ifcopenshell.api.alignment.get_alignment_layout_nest(alignment)
    assert len(layout_nest.RelatedObjects) == 1
    assert layout_nest.RelatedObjects[0].is_a("IfcAlignmentHorizontal")
-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
    assert (
-        len(stationing_nest.RelatedObjects) == 1
+        len(referent_nest.RelatedObjects) == 1
    )  # the alignment creates the stationing nest and it has one referent to defined the stationing for the alignment
-    assert stationing_nest.RelatedObjects[0].is_a("IfcReferent")
+    assert referent_nest.RelatedObjects[0].is_a("IfcReferent")

    curve = ifcopenshell.api.alignment.get_curve(alignment)
    assert curve.is_a("IfcCompositeCurve")
@@ -51,8 +51,8 @@ def test_create_by_pi_method():
    layout_nest = ifcopenshell.api.alignment.get_alignment_layout_nest(alignment)
    assert len(layout_nest.RelatedObjects) == 2

-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
-    assert len(stationing_nest.RelatedObjects) == 1
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
+    assert len(referent_nest.RelatedObjects) == 1

    horizontal_layout = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
    horizontal_segment_nest = ifcopenshell.api.alignment.get_alignment_segment_nest(horizontal_layout)
@@ -46,9 +46,9 @@ def test_horizontal_layout_by_pi_method():

    assert len(alignment.IsDecomposedBy) == 0  # no child alignments
    assert len(alignment.IsNestedBy) == 2
-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
    layout_nest = ifcopenshell.api.alignment.get_alignment_layout_nest(alignment)
-    assert stationing_nest.RelatedObjects[0].is_a("IfcReferent")
+    assert referent_nest.RelatedObjects[0].is_a("IfcReferent")
    assert layout_nest.RelatedObjects[0].is_a("IfcAlignmentHorizontal")
    segment_nest = ifcopenshell.api.alignment.get_alignment_segment_nest(layout_nest.RelatedObjects[0])
    assert len(segment_nest.RelatedObjects) == 3  # segments in horizontal layout
@@ -96,37 +96,17 @@ def callback_alignment():
    yield alignment


-def _label(name):
-    return name.rsplit("(", 1)[1].rstrip(")")
-
-
 def test_with_default_names(default_names_alignment):
-    file = default_names_alignment.file
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(default_names_alignment)
-    vertical = ifcopenshell.api.alignment.get_vertical_layout(default_names_alignment)
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(None, default_names_alignment)

-    h_nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    v_nest = ifcopenshell.api.alignment.update_key_point_referents(file, vertical)
-
-    expected_h = ["P.O.B.", "P.C.", "P.T.", "P.C.", "P.T.", "P.C.", "P.T.", "P.O.E."]
-    expected_v = ["V.P.O.B.", "P.V.C.", "P.V.T.", "P.V.C.", "P.V.T.", "P.V.C.", "P.V.T.", "P.V.C.", "P.V.T.", "V.P.O.E."]
-
-    assert [_label(r.Name) for r in h_nest.RelatedObjects] == expected_h
-    assert [_label(r.Name) for r in v_nest.RelatedObjects] == expected_v
+    expected = ["P.O.B", "P.C.", "P.T.", "P.O.E.", "V.P.O.B.", "P.V.C.", "P.V.T.", "V.P.O.E"]
+    for r in referent_nest.RelatedObjects:
+        assert [x in r.Name for x in expected]


 def test_with_callbacks(callback_alignment):
-    file = callback_alignment.file
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(callback_alignment)
-    vertical = ifcopenshell.api.alignment.get_vertical_layout(callback_alignment)
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(None, callback_alignment)

-    h_nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    v_nest = ifcopenshell.api.alignment.update_key_point_referents(file, vertical)
-
-    expected_h = ["A", "Q", "Q", "Q", "Q", "Q", "Q", "Z"]
-    expected_v = ["a", "q", "q", "q", "q", "q", "q", "q", "q", "z"]
-
-    assert [_label(r.Name) for r in h_nest.RelatedObjects] == expected_h
-    assert [_label(r.Name) for r in v_nest.RelatedObjects] == expected_v
-
-    ifcopenshell.api.alignment.register_referent_name_callback(None, None, None)  # reset global state
+    expected = ["A", "Q", "Z", "a", "q", "z"]
+    for r in referent_nest.RelatedObjects:
+        assert [x in r.Name for x in expected]
@@ -1,307 +0,0 @@
-# IfcOpenShell - IFC toolkit and geometry engine
-# Copyright (C) 2025 Thomas Krijnen <thomas@aecgeeks.com>
-#
-# This file is part of IfcOpenShell.
-#
-# IfcOpenShell is free software: you can redistribute it and/or modify
-# it under the terms of the GNU Lesser General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# IfcOpenShell is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License
-# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
-
-import pytest
-
-import ifcopenshell.api.alignment
-import ifcopenshell.api.context
-import ifcopenshell.api.unit
-import ifcopenshell.util.alignment
-
-COORDINATES = [(500.0, 2500.0), (3340.0, 660.0), (4340.0, 5000.0), (7600.0, 4560.0), (8480.0, 2010.0)]
-RADII = [1000.0, 1250.0, 950.0]
-VPOINTS = [(0.0, 100.0), (2000.0, 135.0), (5000.0, 105.0), (7400.0, 153.0), (9800.0, 105.0), (12800.0, 90.0)]
-LENGTHS = [1600.0, 1200.0, 2000.0, 800.0]
-
-
-def _new_file():
-    file = ifcopenshell.file(schema="IFC4X3")
-    file.createIfcProject(GlobalId=ifcopenshell.guid.new(), Name="Test")
-    length = ifcopenshell.api.unit.add_si_unit(file, unit_type="LENGTHUNIT")
-    ifcopenshell.api.unit.assign_unit(file, units=[length])
-    geometric_representation_context = ifcopenshell.api.context.add_context(file, context_type="Model")
-    ifcopenshell.api.context.add_context(
-        file,
-        context_type="Model",
-        context_identifier="Axis",
-        target_view="MODEL_VIEW",
-        parent=geometric_representation_context,
-    )
-    return file
-
-
-def _new_file_no_context():
-    file = ifcopenshell.file(schema="IFC4X3")
-    file.createIfcProject(GlobalId=ifcopenshell.guid.new(), Name="Test")
-    length = ifcopenshell.api.unit.add_si_unit(file, unit_type="LENGTHUNIT")
-    ifcopenshell.api.unit.assign_unit(file, units=[length])
-    return file
-
-
-def _build_alignment(file, start_station=0.0):
-    return ifcopenshell.api.alignment.create_by_pi_method(
-        file, "TestAlignment", COORDINATES, RADII, VPOINTS, LENGTHS, start_station
-    )
-
-
-def _real_segments(layout):
-    segments = ifcopenshell.api.alignment.get_layout_segments(layout)
-    return segments[:-1] if ifcopenshell.api.alignment.has_zero_length_segment(layout) else segments
-
-
-def _label(tag):
-    return tag.rsplit("(", 1)[1].rstrip(")")
-
-
-def test_wrong_layout_type_raises_type_error():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    with pytest.raises(TypeError):
-        ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, alignment)
-
-
-def test_not_nested_under_alignment_raises_value_error():
-    file = _new_file_no_context()
-    horizontal = file.createIfcAlignmentHorizontal(GlobalId=ifcopenshell.guid.new())
-    with pytest.raises(ValueError):
-        ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal)
-
-
-def test_returns_none():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    result = ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal)
-
-    assert result is None
-
-
-def test_no_referents_or_rel_nests_created():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    referents_before = len(file.by_type("IfcReferent"))
-    rel_nests_before = len(file.by_type("IfcRelNests"))
-
-    ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal)
-
-    assert len(file.by_type("IfcReferent")) == referents_before
-    assert len(file.by_type("IfcRelNests")) == rel_nests_before
-
-
-def test_no_real_segments_leaves_tags_none():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_geometry=False)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    result = ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal)
-
-    assert result is None
-    segments = ifcopenshell.api.alignment.get_layout_segments(horizontal)
-    assert len(segments) == 1  # only the auto zero-length segment
-    assert segments[0].DesignParameters.StartTag is None
-    assert segments[0].DesignParameters.EndTag is None
-
-
-def test_single_real_segment_produces_only_boundary_tags():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_geometry=False)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    design_parameters = file.createIfcAlignmentHorizontalSegment(
-        StartTag=None,
-        EndTag=None,
-        StartPoint=file.createIfcCartesianPoint((0.0, 0.0)),
-        StartDirection=0.0,
-        StartRadiusOfCurvature=0.0,
-        EndRadiusOfCurvature=0.0,
-        SegmentLength=100.0,
-        GravityCenterLineHeight=None,
-        PredefinedType="LINE",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, horizontal, design_parameters)
-
-    ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal, label_end_tag=True)
-
-    segments = _real_segments(horizontal)
-    assert len(segments) == 1
-    dp = segments[0].DesignParameters
-    assert _label(dp.StartTag) == "P.O.B."
-    assert _label(dp.EndTag) == "P.O.E."
-
-
-def test_end_tag_not_labelled_by_default():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_geometry=False)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    design_parameters = file.createIfcAlignmentHorizontalSegment(
-        StartTag=None,
-        EndTag=None,
-        StartPoint=file.createIfcCartesianPoint((0.0, 0.0)),
-        StartDirection=0.0,
-        StartRadiusOfCurvature=0.0,
-        EndRadiusOfCurvature=0.0,
-        SegmentLength=100.0,
-        GravityCenterLineHeight=None,
-        PredefinedType="LINE",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, horizontal, design_parameters)
-
-    ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal)
-
-    segments = _real_segments(horizontal)
-    assert len(segments) == 1
-    dp = segments[0].DesignParameters
-    assert _label(dp.StartTag) == "P.O.B."
-    assert dp.EndTag is None
-
-
-def test_horizontal_tag_labels_and_adjacency():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal, label_end_tag=True)
-
-    segments = _real_segments(horizontal)
-    assert len(segments) == 7
-
-    start_labels = [_label(s.DesignParameters.StartTag) for s in segments]
-    end_labels = [_label(s.DesignParameters.EndTag) for s in segments]
-
-    assert start_labels == ["P.O.B.", "P.C.", "P.T.", "P.C.", "P.T.", "P.C.", "P.T."]
-    assert end_labels == ["P.C.", "P.T.", "P.C.", "P.T.", "P.C.", "P.T.", "P.O.E."]
-
-    # every real segment has both tags set
-    assert all(s.DesignParameters.StartTag is not None for s in segments)
-    assert all(s.DesignParameters.EndTag is not None for s in segments)
-
-    # adjacent segments agree on the tag describing their shared transition point
-    for i in range(len(segments) - 1):
-        assert segments[i].DesignParameters.EndTag == segments[i + 1].DesignParameters.StartTag
-
-
-def test_vertical_tag_labels_and_adjacency():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    vertical = ifcopenshell.api.alignment.get_vertical_layout(alignment)
-
-    ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, vertical, label_end_tag=True)
-
-    segments = _real_segments(vertical)
-    assert len(segments) == 9
-
-    start_labels = [_label(s.DesignParameters.StartTag) for s in segments]
-    end_labels = [_label(s.DesignParameters.EndTag) for s in segments]
-
-    assert start_labels == [
-        "V.P.O.B.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-    ]
-    assert end_labels == [
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "V.P.O.E.",
-    ]
-
-    assert all(s.DesignParameters.StartTag is not None for s in segments)
-    assert all(s.DesignParameters.EndTag is not None for s in segments)
-
-    for i in range(len(segments) - 1):
-        assert segments[i].DesignParameters.EndTag == segments[i + 1].DesignParameters.StartTag
-
-
-def test_cant_layout_boundary_tags():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_cant=True, include_geometry=False)
-    cant = ifcopenshell.api.alignment.get_cant_layout(alignment)
-
-    dp1 = file.createIfcAlignmentCantSegment(
-        StartDistAlong=0.0,
-        HorizontalLength=100.0,
-        StartCantLeft=0.0,
-        EndCantLeft=0.0,
-        StartCantRight=0.0,
-        EndCantRight=0.0,
-        PredefinedType="CONSTANTCANT",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, cant, dp1)
-
-    dp2 = file.createIfcAlignmentCantSegment(
-        StartDistAlong=100.0,
-        HorizontalLength=50.0,
-        StartCantLeft=0.0,
-        EndCantLeft=0.0,
-        StartCantRight=0.0,
-        EndCantRight=0.0,
-        PredefinedType="CONSTANTCANT",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, cant, dp2)
-
-    ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, cant, label_end_tag=True)
-
-    segments = _real_segments(cant)
-    assert _label(segments[0].DesignParameters.StartTag) == "C.P.O.B."
-    assert _label(segments[-1].DesignParameters.EndTag) == "C.P.O.E."
-    # CONSTANTCANT -> CONSTANTCANT is currently an unfilled "xx" placeholder in the cant lookup
-    # table (_get_segment_start_point_label.py) -- out of scope to fill in here.
-    assert _label(segments[0].DesignParameters.EndTag) == "xx"
-    assert _label(segments[-1].DesignParameters.StartTag) == "xx"
-
-
-def test_exact_tag_format():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    ifcopenshell.api.alignment.update_alignment_parameter_segment_tags(file, horizontal)
-
-    start_station = ifcopenshell.api.alignment.get_alignment_start_station(file, alignment)
-    segments = _real_segments(horizontal)
-    assert segments[0].DesignParameters.StartTag == (
-        f"{ifcopenshell.util.alignment.station_as_string(file, start_station)} (P.O.B.)"
-    )
-
-
-test_wrong_layout_type_raises_type_error()
-test_not_nested_under_alignment_raises_value_error()
-test_returns_none()
-test_no_referents_or_rel_nests_created()
-test_no_real_segments_leaves_tags_none()
-test_single_real_segment_produces_only_boundary_tags()
-test_end_tag_not_labelled_by_default()
-test_horizontal_tag_labels_and_adjacency()
-test_vertical_tag_labels_and_adjacency()
-test_cant_layout_boundary_tags()
-test_exact_tag_format()
@@ -1,402 +0,0 @@
-# IfcOpenShell - IFC toolkit and geometry engine
-# Copyright (C) 2025 Thomas Krijnen <thomas@aecgeeks.com>
-#
-# This file is part of IfcOpenShell.
-#
-# IfcOpenShell is free software: you can redistribute it and/or modify
-# it under the terms of the GNU Lesser General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# IfcOpenShell is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License
-# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
-
-from collections import Counter
-
-import pytest
-
-import ifcopenshell.api.alignment
-import ifcopenshell.api.context
-import ifcopenshell.api.unit
-import ifcopenshell.util.alignment
-import ifcopenshell.util.element
-
-COORDINATES = [(500.0, 2500.0), (3340.0, 660.0), (4340.0, 5000.0), (7600.0, 4560.0), (8480.0, 2010.0)]
-RADII = [1000.0, 1250.0, 950.0]
-VPOINTS = [(0.0, 100.0), (2000.0, 135.0), (5000.0, 105.0), (7400.0, 153.0), (9800.0, 105.0), (12800.0, 90.0)]
-LENGTHS = [1600.0, 1200.0, 2000.0, 800.0]
-
-
-def _new_file():
-    file = ifcopenshell.file(schema="IFC4X3")
-    file.createIfcProject(GlobalId=ifcopenshell.guid.new(), Name="Test")
-    length = ifcopenshell.api.unit.add_si_unit(file, unit_type="LENGTHUNIT")
-    ifcopenshell.api.unit.assign_unit(file, units=[length])
-    geometric_representation_context = ifcopenshell.api.context.add_context(file, context_type="Model")
-    ifcopenshell.api.context.add_context(
-        file,
-        context_type="Model",
-        context_identifier="Axis",
-        target_view="MODEL_VIEW",
-        parent=geometric_representation_context,
-    )
-    return file
-
-
-def _new_file_no_context():
-    file = ifcopenshell.file(schema="IFC4X3")
-    file.createIfcProject(GlobalId=ifcopenshell.guid.new(), Name="Test")
-    length = ifcopenshell.api.unit.add_si_unit(file, unit_type="LENGTHUNIT")
-    ifcopenshell.api.unit.assign_unit(file, units=[length])
-    return file
-
-
-def _build_alignment(file, start_station=0.0):
-    return ifcopenshell.api.alignment.create_by_pi_method(
-        file, "TestAlignment", COORDINATES, RADII, VPOINTS, LENGTHS, start_station
-    )
-
-
-def _pset_station(referent):
-    return ifcopenshell.util.element.get_pset(referent, name="Pset_Stationing", prop="Station")
-
-
-def _label(name):
-    return name.rsplit("(", 1)[1].rstrip(")")
-
-
-def test_wrong_layout_type_raises_type_error():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    with pytest.raises(TypeError):
-        ifcopenshell.api.alignment.update_key_point_referents(file, alignment)
-
-
-def test_default_rel_nests_created_when_none_provided():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-    segment_nest = ifcopenshell.api.alignment.get_alignment_segment_nest(horizontal)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-
-    assert nest.is_a("IfcRelNests")
-    assert nest.RelatingObject == alignment
-    assert nest.id() != segment_nest.id()
-    assert len(nest.RelatedObjects) == 8
-    assert all(r.is_a("IfcReferent") for r in nest.RelatedObjects)
-
-
-def test_second_call_without_rel_nests_creates_separate_nest():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-    segment_count_before = len(ifcopenshell.api.alignment.get_alignment_segment_nest(horizontal).RelatedObjects)
-
-    nest1 = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    nest2 = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-
-    assert nest1.id() != nest2.id()
-    assert len(nest1.RelatedObjects) == 8
-    assert len(nest2.RelatedObjects) == 8
-    segment_count_after = len(ifcopenshell.api.alignment.get_alignment_segment_nest(horizontal).RelatedObjects)
-    assert segment_count_after == segment_count_before
-
-
-def test_passing_previous_nest_back_in_accumulates():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    nest1 = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    nest2 = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal, rel_nests=nest1)
-
-    assert nest1.id() == nest2.id()
-    assert len(nest2.RelatedObjects) == 16
-
-
-def test_provided_rel_nests_is_used_as_is():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    # rel_nests.RelatingObject must be the IfcAlignment that nests `layout`
-    rel_nests = file.createIfcRelNests(GlobalId=ifcopenshell.guid.new(), RelatingObject=alignment, RelatedObjects=())
-
-    result = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal, rel_nests=rel_nests)
-
-    assert result.id() == rel_nests.id()
-    assert result.RelatingObject == alignment
-    assert len(result.RelatedObjects) == 8
-
-
-def test_provided_rel_nests_with_wrong_relating_object_raises_type_error():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    rel_nests = file.createIfcRelNests(GlobalId=ifcopenshell.guid.new(), RelatingObject=horizontal, RelatedObjects=())
-
-    with pytest.raises(TypeError):
-        ifcopenshell.api.alignment.update_key_point_referents(file, horizontal, rel_nests=rel_nests)
-
-
-def test_clear_true_removes_old_referents_and_psets():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    old_referent_ids = [r.id() for r in nest.RelatedObjects]
-    old_pset_ids = [r.IsDefinedBy[0].RelatingPropertyDefinition.id() for r in nest.RelatedObjects]
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal, rel_nests=nest, clear=True)
-
-    assert len(nest.RelatedObjects) == 8
-    for old_id in old_referent_ids + old_pset_ids:
-        with pytest.raises(RuntimeError):
-            file.by_id(old_id)
-
-
-def test_clear_false_appends_without_dedup():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    ifcopenshell.api.alignment.update_key_point_referents(file, horizontal, rel_nests=nest, clear=False)
-
-    assert len(nest.RelatedObjects) == 16
-    counts = Counter(r.Name for r in nest.RelatedObjects)
-    assert len(counts) == 8
-    assert all(count == 2 for count in counts.values())
-
-
-def test_default_horizontal_labels_and_order():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-
-    expected = ["P.O.B.", "P.C.", "P.T.", "P.C.", "P.T.", "P.C.", "P.T.", "P.O.E."]
-    assert [_label(r.Name) for r in nest.RelatedObjects] == expected
-
-    stations = [_pset_station(r) for r in nest.RelatedObjects]
-    assert stations == sorted(stations)
-    assert stations[0] == 0.0
-
-
-def test_default_vertical_labels_and_order():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    vertical = ifcopenshell.api.alignment.get_vertical_layout(alignment)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, vertical)
-
-    expected = [
-        "V.P.O.B.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "P.V.C.",
-        "P.V.T.",
-        "V.P.O.E.",
-    ]
-    assert [_label(r.Name) for r in nest.RelatedObjects] == expected
-
-    segments = ifcopenshell.api.alignment.get_layout_segments(vertical)
-    real_segments = segments[:-1] if ifcopenshell.api.alignment.has_zero_length_segment(vertical) else segments
-    # spot check the interior referents' stations against the segments' StartDistAlong directly
-    for referent, segment in zip(nest.RelatedObjects[1:-1], real_segments[1:]):
-        assert _pset_station(referent) == pytest.approx(segment.DesignParameters.StartDistAlong)
-
-
-def test_name_format():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    referent = nest.RelatedObjects[0]
-    station = _pset_station(referent)
-    assert referent.Name == f"{alignment.Name} {ifcopenshell.util.alignment.station_as_string(file, station)} (P.O.B.)"
-
-
-def test_geometric_placement_when_layout_has_representation():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-    curve = ifcopenshell.api.alignment.get_layout_curve(horizontal)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-
-    for referent in nest.RelatedObjects:
-        assert referent.ObjectPlacement.is_a("IfcLinearPlacement")
-        location = referent.ObjectPlacement.RelativePlacement.Location
-        assert location.is_a("IfcPointByDistanceExpression")
-        assert location.BasisCurve == curve
-        assert referent.ObjectPlacement.CartesianPosition is not None
-
-    first, last = nest.RelatedObjects[0], nest.RelatedObjects[-1]
-    assert first.ObjectPlacement.RelativePlacement.Location.DistanceAlong.wrappedValue == pytest.approx(0.0)
-    assert last.ObjectPlacement.RelativePlacement.Location.DistanceAlong.wrappedValue == pytest.approx(
-        _pset_station(last)
-    )
-
-
-def test_fallback_placement_when_layout_has_no_geometry():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_geometry=False)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-    ifcopenshell.api.alignment.layout_horizontal_alignment_by_pi_method(file, horizontal, COORDINATES, RADII)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-
-    expected_coordinates = alignment.ObjectPlacement.RelativePlacement.Location.Coordinates
-    for referent in nest.RelatedObjects:
-        assert referent.ObjectPlacement.is_a("IfcLocalPlacement")
-        assert referent.ObjectPlacement.RelativePlacement.Location.Coordinates == expected_coordinates
-
-
-def test_cant_layout_boundary_labels():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_cant=True, include_geometry=False)
-    cant = ifcopenshell.api.alignment.get_cant_layout(alignment)
-
-    dp1 = file.createIfcAlignmentCantSegment(
-        StartDistAlong=0.0,
-        HorizontalLength=100.0,
-        StartCantLeft=0.0,
-        EndCantLeft=0.0,
-        StartCantRight=0.0,
-        EndCantRight=0.0,
-        PredefinedType="CONSTANTCANT",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, cant, dp1)
-
-    dp2 = file.createIfcAlignmentCantSegment(
-        StartDistAlong=100.0,
-        HorizontalLength=50.0,
-        StartCantLeft=0.0,
-        EndCantLeft=0.0,
-        StartCantRight=0.0,
-        EndCantRight=0.0,
-        PredefinedType="CONSTANTCANT",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, cant, dp2)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, cant)
-
-    labels = [_label(r.Name) for r in nest.RelatedObjects]
-    assert labels[0] == "C.P.O.B."
-    assert labels[-1] == "C.P.O.E."
-    # CONSTANTCANT -> CONSTANTCANT is currently an unfilled "xx" placeholder in the cant lookup
-    # table (_get_segment_start_point_label.py) -- out of scope to fill in here.
-    assert labels[1] == "xx"
-
-    stations = [_pset_station(r) for r in nest.RelatedObjects]
-    assert stations == [0.0, 100.0, 150.0]
-
-
-def test_no_real_segments_produces_no_referents():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_geometry=False)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    assert nest.RelatedObjects == ()
-
-
-def test_single_real_segment_produces_only_boundary_labels():
-    file = _new_file_no_context()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_geometry=False)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    design_parameters = file.createIfcAlignmentHorizontalSegment(
-        StartTag=None,
-        EndTag=None,
-        StartPoint=file.createIfcCartesianPoint((0.0, 0.0)),
-        StartDirection=0.0,
-        StartRadiusOfCurvature=0.0,
-        EndRadiusOfCurvature=0.0,
-        SegmentLength=100.0,
-        GravityCenterLineHeight=None,
-        PredefinedType="LINE",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, horizontal, design_parameters)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    labels = [_label(r.Name) for r in nest.RelatedObjects]
-    assert labels == ["P.O.B.", "P.O.E."]
-
-
-def test_start_station_composes_for_child_alignment():
-    file = _new_file()
-    alignment = ifcopenshell.api.alignment.create(file, "A1", include_vertical=False, start_station=100.0)
-    ifcopenshell.api.alignment.add_vertical_layout(file, alignment)
-    ifcopenshell.api.alignment.add_vertical_layout(file, alignment)  # forces the child-alignment split
-
-    child_alignment = alignment.IsDecomposedBy[0].RelatedObjects[-1]
-    child_vertical = ifcopenshell.api.alignment.get_vertical_layout(child_alignment)
-
-    dp1 = file.createIfcAlignmentVerticalSegment(
-        StartDistAlong=0.0,
-        HorizontalLength=500.0,
-        StartHeight=10.0,
-        StartGradient=0.01,
-        EndGradient=0.01,
-        PredefinedType="CONSTANTGRADIENT",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, child_vertical, dp1)
-
-    dp2 = file.createIfcAlignmentVerticalSegment(
-        StartDistAlong=500.0,
-        HorizontalLength=300.0,
-        StartHeight=15.0,
-        StartGradient=0.01,
-        EndGradient=0.01,
-        PredefinedType="CONSTANTGRADIENT",
-    )
-    ifcopenshell.api.alignment.create_layout_segment(file, child_vertical, dp2)
-
-    nest = ifcopenshell.api.alignment.update_key_point_referents(file, child_vertical)
-    stations = [_pset_station(r) for r in nest.RelatedObjects]
-    assert stations == pytest.approx([100.0, 600.0, 900.0])
-
-
-def test_returns_ifc_rel_nests():
-    file = _new_file()
-    alignment = _build_alignment(file)
-    horizontal = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
-
-    result = ifcopenshell.api.alignment.update_key_point_referents(file, horizontal)
-    assert result.is_a("IfcRelNests")
-
-
-test_wrong_layout_type_raises_type_error()
-test_default_rel_nests_created_when_none_provided()
-test_second_call_without_rel_nests_creates_separate_nest()
-test_passing_previous_nest_back_in_accumulates()
-test_provided_rel_nests_is_used_as_is()
-test_provided_rel_nests_with_wrong_relating_object_raises_type_error()
-test_clear_true_removes_old_referents_and_psets()
-test_clear_false_appends_without_dedup()
-test_default_horizontal_labels_and_order()
-test_default_vertical_labels_and_order()
-test_name_format()
-test_geometric_placement_when_layout_has_representation()
-test_fallback_placement_when_layout_has_no_geometry()
-test_cant_layout_boundary_labels()
-test_no_real_segments_produces_no_referents()
-test_single_real_segment_produces_only_boundary_labels()
-test_start_station_composes_for_child_alignment()
-test_returns_ifc_rel_nests()
@@ -64,8 +64,8 @@ def test_vertical_layout_by_pi_method():
    layout_nest = ifcopenshell.api.alignment.get_alignment_layout_nest(alignment)
    assert len(layout_nest.RelatedObjects) == 2

-    stationing_nest = ifcopenshell.api.alignment.get_stationing_nest(file, alignment)
-    assert len(stationing_nest.RelatedObjects) == 1
+    referent_nest = ifcopenshell.api.alignment.get_referent_nest(file, alignment)
+    assert len(referent_nest.RelatedObjects) == 1

    segment_nest = ifcopenshell.api.alignment.get_alignment_segment_nest(vlayout)
    assert len(segment_nest.RelatedObjects) == 3
@@ -188,36 +188,6 @@ class TestEditPsetIFC2X3(test.bootstrap.IFC2X3):
        assert unit.Prefix == "GIGA"
        assert unit.Name == "PASCAL"

-    def test_explicitly_clearing_a_propertys_unit_override(self):
-        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-        custom_unit = self.file.createIfcSIUnit(UnitType="PRESSUREUNIT", Prefix="GIGA", Name="PASCAL")
-        pset = ifcopenshell.api.pset.add_pset(self.file, product=element, name="Foo_Bar")
-        ifcopenshell.api.pset.edit_pset(
-            self.file, pset=pset, properties={"MyCustom": {"NominalValue": 30.0, "Unit": custom_unit}}
-        )
-        prop = pset.HasProperties[0]
-        assert prop.Unit == custom_unit
-
-        ifcopenshell.api.pset.edit_pset(
-            self.file, pset=pset, properties={"MyCustom": {"NominalValue": 40.0, "Unit": None}}
-        )
-        assert prop.Unit is None
-        assert prop.NominalValue.wrappedValue == 40.0
-
-    def test_a_bare_value_does_not_disturb_an_existing_units_override(self):
-        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-        custom_unit = self.file.createIfcSIUnit(UnitType="PRESSUREUNIT", Prefix="GIGA", Name="PASCAL")
-        pset = ifcopenshell.api.pset.add_pset(self.file, product=element, name="Foo_Bar")
-        ifcopenshell.api.pset.edit_pset(
-            self.file, pset=pset, properties={"MyCustom": {"NominalValue": 30.0, "Unit": custom_unit}}
-        )
-        prop = pset.HasProperties[0]
-        assert prop.Unit == custom_unit
-
-        ifcopenshell.api.pset.edit_pset(self.file, pset=pset, properties={"MyCustom": 42.0})
-        assert prop.Unit == custom_unit
-        assert prop.NominalValue.wrappedValue == 42.0
-
    def test_editing_properties_of_non_rooted_elements(self):
        element = self.file.createIfcMaterial()
        pset = ifcopenshell.api.pset.add_pset(self.file, product=element, name="Foo_Bar")
@@ -18,7 +18,6 @@

 import ifcopenshell.api.pset
 import ifcopenshell.api.root
-import ifcopenshell.api.unit
 import test.bootstrap


@@ -151,87 +150,3 @@ class TestEditQto(test.bootstrap.IFC4):
        qto = element.IsDefinedBy[0].RelatingPropertyDefinition
        assert qto.Quantities[0].Name == "MyLength"
        assert qto.Quantities[0].LengthValue == 34
-
-    def test_adding_a_new_quantity_with_a_custom_unit(self):
-        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-        custom_unit = self.file.createIfcSIUnit(UnitType="LENGTHUNIT", Prefix="MILLI", Name="METRE")
-        qto = ifcopenshell.api.pset.add_qto(self.file, product=element, name="Foo_Bar")
-        ifcopenshell.api.pset.edit_qto(
-            self.file, qto=qto, properties={"MyLength": {"NominalValue": 30.0, "Unit": custom_unit}}
-        )
-        qto = element.IsDefinedBy[0].RelatingPropertyDefinition
-        assert qto.Quantities[0].Name == "MyLength"
-        assert qto.Quantities[0].LengthValue == 30.0
-        assert qto.Quantities[0].Unit == custom_unit
-
-    def test_editing_an_existing_quantitys_unit(self):
-        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-        custom_unit = self.file.createIfcSIUnit(UnitType="LENGTHUNIT", Prefix="MILLI", Name="METRE")
-        qto = ifcopenshell.api.pset.add_qto(self.file, product=element, name="Foo_Bar")
-        ifcopenshell.api.pset.edit_qto(self.file, qto=qto, properties={"MyLength": 12.0})
-        quantity = qto.Quantities[0]
-        assert quantity.Unit is None
-
-        ifcopenshell.api.pset.edit_qto(
-            self.file, qto=qto, properties={"MyLength": {"NominalValue": 30.0, "Unit": custom_unit}}
-        )
-        assert quantity.Unit == custom_unit
-        assert quantity.LengthValue == 30.0
-
-    def test_explicitly_clearing_a_quantitys_unit_override(self):
-        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-        custom_unit = self.file.createIfcSIUnit(UnitType="LENGTHUNIT", Prefix="MILLI", Name="METRE")
-        qto = ifcopenshell.api.pset.add_qto(self.file, product=element, name="Foo_Bar")
-        ifcopenshell.api.pset.edit_qto(
-            self.file, qto=qto, properties={"MyLength": {"NominalValue": 30.0, "Unit": custom_unit}}
-        )
-        quantity = qto.Quantities[0]
-        assert quantity.Unit == custom_unit
-
-        ifcopenshell.api.pset.edit_qto(
-            self.file, qto=qto, properties={"MyLength": {"NominalValue": 40.0, "Unit": None}}
-        )
-        assert quantity.Unit is None
-        assert quantity.LengthValue == 40.0
-
-    def test_a_bare_value_does_not_disturb_an_existing_units_override(self):
-        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-        custom_unit = self.file.createIfcSIUnit(UnitType="LENGTHUNIT", Prefix="MILLI", Name="METRE")
-        qto = ifcopenshell.api.pset.add_qto(self.file, product=element, name="Foo_Bar")
-        ifcopenshell.api.pset.edit_qto(
-            self.file, qto=qto, properties={"MyLength": {"NominalValue": 30.0, "Unit": custom_unit}}
-        )
-        quantity = qto.Quantities[0]
-        assert quantity.Unit == custom_unit
-
-        ifcopenshell.api.pset.edit_qto(self.file, qto=qto, properties={"MyLength": 42.0})
-        assert quantity.Unit == custom_unit
-        assert quantity.LengthValue == 42.0
-
-    def test_complex_quantity_editing_is_unaffected_by_the_unit_wrapper_convention(self):
-        # Regression guard: dict values are already overloaded to mean "this is an
-        # IfcPhysicalComplexQuantity spec" ({"Discrimination": ..., "HasQuantities": ...}).
-        # The new {"Unit": ..., "NominalValue": ...} convention must not be confused with it.
-        element = ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcWall")
-        qto = ifcopenshell.api.pset.add_qto(self.file, product=element, name="Foo_Bar")
-        ifcopenshell.api.pset.edit_qto(
-            self.file,
-            qto=qto,
-            properties={"Layers": {"Discrimination": "layer", "HasQuantities": {"Width": 5.0}}},
-        )
-        qto = element.IsDefinedBy[0].RelatingPropertyDefinition
-        complex_qty = qto.Quantities[0]
-        assert complex_qty.is_a("IfcPhysicalComplexQuantity")
-        assert complex_qty.Name == "Layers"
-        assert complex_qty.Discrimination == "layer"
-        assert complex_qty.HasQuantities[0].Name == "Width"
-        assert complex_qty.HasQuantities[0].LengthValue == 5.0
-
-        # Editing it again (update_existing_property's complex-quantity branch) still works too.
-        ifcopenshell.api.pset.edit_qto(
-            self.file,
-            qto=qto,
-            properties={"Layers": {"Discrimination": "layer2", "HasQuantities": {"Width": 6.0}}},
-        )
-        assert complex_qty.Discrimination == "layer2"
-        assert complex_qty.HasQuantities[0].LengthValue == 6.0
@@ -1,7 +0,0 @@
-def pytest_addoption(parser):
-    parser.addoption(
-        "--rule",
-        action="store",
-        default=None,
-        help="Only run test_rules.py fixtures whose filename contains this substring.",
-    )
@@ -1,5 +1,6 @@
 import glob
 import os
+import sys

 import pytest
 import tabulate
@@ -8,18 +9,14 @@ import ifcopenshell.express.rule_executor
 import ifcopenshell.validate


-def pytest_generate_tests(metafunc):
-    if "filename" not in metafunc.fixturenames:
-        return
-    rule = metafunc.config.getoption("--rule")
-    filenames = [
+@pytest.mark.parametrize(
+    "filename",
+    [
        fn
        for fn in glob.glob(os.path.join(os.path.dirname(__file__), "fixtures/rules/*.ifc"))
-        if not rule or rule in os.path.basename(fn)
-    ]
-    metafunc.parametrize("filename", filenames, ids=[os.path.basename(fn) for fn in filenames])
-
-
+        if len(sys.argv) < 2 or sys.argv[1] in os.path.basename(fn)
+    ],
+)
 def test_file(filename):
    base = os.path.basename(filename)
    file = ifcopenshell.open(filename)
@@ -16,9 +16,7 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.

-import tempfile
 from math import pi
-from pathlib import Path

 import numpy as np
 import pytest
@@ -31,10 +29,8 @@ import ifcopenshell.api.unit
 import ifcopenshell.util.element
 import ifcopenshell.util.geolocation
 import ifcopenshell.util.unit as subject
-import ifcpatch
 import test.bootstrap
 from ifcopenshell.util.shape_builder import ShapeBuilder
-from ifcpatch.recipes import Ifc2Sql


 class TestMmToM:
@@ -94,80 +90,6 @@ class TestGetProjectUnit(test.bootstrap.IFC4):
        assert subject.get_project_unit(self.file, "LENGTHUNIT", use_cache=True) == length2
        assert self.file.units == {"LENGTHUNIT": length2, "AREAUNIT": area}

-    def test_area_and_volume_derived_from_length_are_matched_dimensionally(self):
-        # AREAUNIT/VOLUMEUNIT have no IfcDerivedUnitEnum member, so a project whose area/volume
-        # default is an IfcDerivedUnit has no literal UnitType match for either -- get_project_unit
-        # must still resolve them by dimensional analysis, like get_candidate_units already does.
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        length = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT")
-        area = ifcopenshell.api.unit.add_derived_unit(self.file, "USERDEFINED", "area-ish", {length: 2})
-        volume = ifcopenshell.api.unit.add_derived_unit(self.file, "USERDEFINED", "volume-ish", {length: 3})
-        ifcopenshell.api.unit.assign_unit(self.file, units=[length, area, volume])
-
-        assert subject.get_project_unit(self.file, "AREAUNIT") == area
-        assert subject.get_project_unit(self.file, "VOLUMEUNIT") == volume
-
-    def test_literal_unit_type_match_takes_priority_over_dimensional(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        length = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT")
-        literal_area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT")
-        derived_area = ifcopenshell.api.unit.add_derived_unit(self.file, "USERDEFINED", "area-ish", {length: 2})
-        ifcopenshell.api.unit.assign_unit(self.file, units=[length, literal_area, derived_area])
-
-        assert subject.get_project_unit(self.file, "AREAUNIT") == literal_area
-
-    def test_dimensional_fallback_also_applies_when_using_a_cache(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        length = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT")
-        area = ifcopenshell.api.unit.add_derived_unit(self.file, "USERDEFINED", "area-ish", {length: 2})
-        ifcopenshell.api.unit.assign_unit(self.file, units=[length, area])
-
-        assert subject.get_project_unit(self.file, "AREAUNIT", use_cache=True) == area
-        assert self.file.units["AREAUNIT"] == area
-
-
-class TestGetCandidateUnits(test.bootstrap.IFC4):
-    def test_returns_only_units_matching_the_unit_type(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        mm = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT", prefix="MILLI")
-        m = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT")
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT")
-        candidates = subject.get_candidate_units(self.file, "LENGTHUNIT")
-        assert set(candidates) == {mm, m}
-        assert area not in candidates
-
-    def test_returns_all_matching_units_not_just_the_assigned_default(self):
-        # Unlike get_project_unit, which only returns the one assigned default.
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        mm = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT", prefix="MILLI")
-        m = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT")
-        ifcopenshell.api.unit.assign_unit(self.file, units=[mm])
-        assert subject.get_project_unit(self.file, "LENGTHUNIT") == mm
-        assert set(subject.get_candidate_units(self.file, "LENGTHUNIT")) == {mm, m}
-
-    def test_derived_unit_matched_by_literal_unit_type(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT")
-        modulus = ifcopenshell.api.unit.add_derived_unit(self.file, "MODULUSOFELASTICITYUNIT", None, {force: 1, area: -1})
-        assert subject.get_candidate_units(self.file, "MODULUSOFELASTICITYUNIT") == [modulus]
-
-    def test_userdefined_derived_unit_matched_by_dimensional_fallback(self):
-        # No literal UnitType match (USERDEFINED), but dimensionally it's a pressure unit,
-        # and PRESSUREUNIT is one of the core families covered by named_dimensions.
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT")
-        weird_pressure = ifcopenshell.api.unit.add_derived_unit(
-            self.file, "USERDEFINED", "pressure-ish", {force: 1, area: -1}
-        )
-        assert subject.get_candidate_units(self.file, "PRESSUREUNIT") == [weird_pressure]
-
-    def test_empty_when_nothing_matches(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT")
-        assert subject.get_candidate_units(self.file, "MASSUNIT") == []
-

 class TestGetPropertyUnit(test.bootstrap.IFC4):
    def test_no_unit(self):
@@ -197,12 +119,6 @@ class TestGetPropertyUnit(test.bootstrap.IFC4):
        prop.Unit = length2
        assert subject.get_property_unit(prop, self.file) == length2

-    def test_single_value_with_no_nominal_value(self):
-        # NominalValue is optional -- a property may be null. Must not crash.
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        prop = self.file.createIfcPropertySingleValue(Name="Foo", NominalValue=None)
-        assert subject.get_property_unit(prop, self.file) is None
-
    def test_enumerated_value(self):
        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
        length = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT", prefix="MILLI")
@@ -284,152 +200,6 @@ class TestCalculateUnitScale(test.bootstrap.IFC4):
        ifcopenshell.api.unit.assign_unit(self.file, units=[angle])
        assert subject.calculate_unit_scale(self.file, "PLANEANGLEUNIT") == pi / 180 * 0.001

-    def test_derived_units_are_considered(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT", prefix="MILLI")
-        modulus = ifcopenshell.api.unit.add_derived_unit(self.file, "MODULUSOFELASTICITYUNIT", None, {force: 1, area: -1})
-        ifcopenshell.api.unit.assign_unit(self.file, units=[modulus])
-        # AREAUNIT is a pure power of length, so its MILLI prefix is raised to
-        # the length exponent (2) per #9278: (1e-3)**2 = 1e-6, inverted by the
-        # derived unit's -1 exponent to give 1e6.
-        assert subject.calculate_unit_scale(self.file, "MODULUSOFELASTICITYUNIT") == pytest.approx(1_000_000.0)
-
-    def test_prefix_is_raised_to_the_length_exponent_for_area_and_volume(self):
-        # A prefixed square/cubic metre is (prefix-metre) squared/cubed:
-        # DECI SQUARE_METRE = dm2 = 1e-2 m2, DECI CUBIC_METRE = dm3 (litre) = 1e-3 m3.
-        # https://github.com/IfcOpenShell/IfcOpenShell/issues/9278
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT")
-        area.Prefix = "DECI"
-        volume = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="VOLUMEUNIT")
-        volume.Prefix = "DECI"
-        ifcopenshell.api.unit.assign_unit(self.file, units=[area, volume])
-        assert subject.calculate_unit_scale(self.file, "AREAUNIT") == pytest.approx(0.1**2)
-        assert subject.calculate_unit_scale(self.file, "VOLUMEUNIT") == pytest.approx(0.1**3)
-
-    def test_prefix_stays_linear_for_units_that_are_not_a_pure_power_of_length(self):
-        # For derived and non-length SI units the prefix scales the unit itself:
-        # KILO PASCAL = 1e3 Pa, KILO GRAM = 1e3 g.
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        pressure = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="PRESSUREUNIT")
-        pressure.Prefix = "KILO"
-        mass = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="MASSUNIT")
-        mass.Prefix = "KILO"
-        ifcopenshell.api.unit.assign_unit(self.file, units=[pressure, mass])
-        assert subject.calculate_unit_scale(self.file, "PRESSUREUNIT") == pytest.approx(1000)
-        assert subject.calculate_unit_scale(self.file, "MASSUNIT") == pytest.approx(1000)
-
-
-class TestCalculateUnitScaleOnLinkedFile(test.bootstrap.IFC4):
-    def test_run(self):
-        # Regression test: IfcSIUnit.Dimensions is a schema-*derived*
-        # attribute that isn't computed for SQLite-linked files (used for
-        # Bonsai's "linked project" large-model workflow), so it returns None
-        # there instead of an IfcDimensionalExponents entity. calculate_unit_scale()
-        # used to access unit.Dimensions.LengthExponent unconditionally for
-        # every IfcSIUnit, which crashed project loading for any linked file.
-        # See the PR discussion for a standalone reproduction script.
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        length = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT")
-        ifcopenshell.api.unit.assign_unit(self.file, units=[length])
-
-        patcher = Ifc2Sql.Patcher(self.file, sql_type="SQLite")
-        patcher.patch()
-        tmp_file = Path(tempfile.mkstemp(suffix=".ifcsqlite")[1])
-        ifcpatch.write(patcher.get_output(), tmp_file)
-
-        try:
-            linked_file = ifcopenshell.open(str(tmp_file))
-            assert linked_file.by_type("IfcSIUnit")[0].Dimensions is None
-            assert subject.calculate_unit_scale(linked_file, "LENGTHUNIT") == 1.0
-        finally:
-            if isinstance(linked_file, ifcopenshell.sqlite):
-                linked_file.db.close()
-            tmp_file.unlink(missing_ok=True)
-
-
-class TestGetNamedUnitScale(test.bootstrap.IFC4):
-    def test_prefix_is_raised_to_the_length_exponent_for_area_and_volume(self):
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT", prefix="DECI")
-        assert subject.get_named_unit_scale(area) == pytest.approx(0.1**2)
-
-    def test_prefix_stays_linear_for_units_that_are_not_a_pure_power_of_length(self):
-        pressure = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="PRESSUREUNIT", prefix="KILO")
-        assert subject.get_named_unit_scale(pressure) == pytest.approx(1000)
-
-
-class TestGetDerivedUnitScale(test.bootstrap.IFC4):
-    def test_composes_scale_from_elements(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        mass = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="MASSUNIT", prefix="KILO")
-        volume = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="VOLUMEUNIT")
-        density = ifcopenshell.api.unit.add_derived_unit(self.file, "MASSDENSITYUNIT", None, {mass: 1, volume: -1})
-        assert subject.get_derived_unit_scale(density) == 1000.0
-
-    def test_unnamed_derived_unit_still_composes(self):
-        # A made-up "force per unit time" derived unit with no IfcDerivedUnitEnum match.
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        time = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="TIMEUNIT", prefix="MILLI")
-        weird = ifcopenshell.api.unit.add_derived_unit(self.file, "USERDEFINED", "force per time", {force: 1, time: -1})
-        assert subject.get_derived_unit_scale(weird) == pytest.approx(1 / 0.001)
-
-
-class TestGetUnitScale(test.bootstrap.IFC4):
-    def test_dispatches_to_named_unit_scale_for_si_and_conversion_based_units(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        mm = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="LENGTHUNIT", prefix="MILLI")
-        ft = ifcopenshell.api.unit.add_conversion_based_unit(self.file, name="foot")
-        assert subject.get_unit_scale(mm) == subject.get_named_unit_scale(mm)
-        assert subject.get_unit_scale(ft) == subject.get_named_unit_scale(ft)
-
-    def test_dispatches_to_derived_unit_scale_for_derived_units(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        mass = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="MASSUNIT", prefix="KILO")
-        volume = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="VOLUMEUNIT")
-        density = ifcopenshell.api.unit.add_derived_unit(self.file, "MASSDENSITYUNIT", None, {mass: 1, volume: -1})
-        assert subject.get_unit_scale(density) == subject.get_derived_unit_scale(density)
-
-
-class TestGetUnitSymbol(test.bootstrap.IFC4):
-    def test_derived_unit_composes_a_symbol(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT")
-        modulus = ifcopenshell.api.unit.add_derived_unit(self.file, "MODULUSOFELASTICITYUNIT", None, {force: 1, area: -1})
-        assert subject.get_unit_symbol(modulus) == "N/m2"
-
-    def test_unnamed_derived_unit_still_composes_a_symbol_without_crashing(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        time = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="TIMEUNIT")
-        weird = ifcopenshell.api.unit.add_derived_unit(self.file, "USERDEFINED", "force per time", {force: 1, time: -1})
-        assert subject.get_unit_symbol(weird) == "N/s"
-
-    def test_context_dependent_userdefined_unit_is_not_shadowed_by_the_derived_unit_check(self):
-        # IfcContextDependentUnit (e.g. "each", "boxes") is a distinct entity
-        # from IfcDerivedUnit, so the is_a("IfcDerivedUnit") check added for
-        # derived-unit symbol composition must not shadow this fallback.
-        each = ifcopenshell.api.unit.add_context_dependent_unit(self.file, name="EACH")
-        assert subject.get_unit_symbol(each) == "EACH"
-
-
-class TestIdentifyUnitDimensions(test.bootstrap.IFC4):
-    def test_matches_a_named_unit_type_by_dimension(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        area = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="AREAUNIT")
-        modulus = ifcopenshell.api.unit.add_derived_unit(self.file, "MODULUSOFELASTICITYUNIT", None, {force: 1, area: -1})
-        assert subject.identify_unit_dimensions(modulus) == "PRESSUREUNIT"
-
-    def test_returns_none_for_no_match(self):
-        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
-        force = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="FORCEUNIT")
-        time = ifcopenshell.api.unit.add_si_unit(self.file, unit_type="TIMEUNIT")
-        weird = ifcopenshell.api.unit.add_derived_unit(self.file, "USERDEFINED", "force per time", {force: 1, time: -1})
-        assert subject.identify_unit_dimensions(weird) is None
-

 class TestFormatLength(test.bootstrap.IFC4):
    def test_run(self):
@@ -46,13 +46,6 @@ struct FullBufferImpl final : FileReader::Impl {
 #else
        auto stream = fopen(fn.c_str(), "rb");
 #endif
-        if (stream == nullptr) {
-            // Missing or unreadable file. Leave the buffer empty so the
-            // caller sees a zero-length input and reports a read error;
-            // handing a null FILE* to the CRT below terminates the whole
-            // process instead of failing the parse.
-            return;
-        }
        fseek(stream, 0, SEEK_END);
        buf_.resize((size_t)ftell(stream));
        rewind(stream);
@@ -91,13 +84,6 @@ struct PagedFileImpl final : FileReader::Impl {
 #else
        fp_ = fopen(fn.c_str(), "rb");
 #endif
-        if (fp_ == nullptr) {
-            // As above: behave like an empty file rather than passing a
-            // null FILE* to fseek. get() then throws out_of_range for any
-            // position and fetchPage_() is never reached.
-            file_size_ = 0;
-            return;
-        }
        fseek(fp_, 0, SEEK_END);
        file_size_ = (size_t)ftell(fp_);
        rewind(fp_);
@@ -47,10 +47,6 @@ class Patcher:

        This is for AGS version 3.

-        The input file is not read. A new IFC4X3 model is built from the AGS
-        data, containing one IfcBorehole per location with its strata nested
-        inside as IfcGeotechnicalStratum.
-
        :param ags_file: The AGS file to convert.
        :filter_glob ags_file: *.ags
        :param docs_dir: The directory URI where documents are stored
@@ -59,8 +55,8 @@ class Patcher:

        .. code:: python

-            result = ifcpatch.execute({"file": model, "recipe": "AGS2IFC", "arguments": ["data.ags", "docs"]})
-            ifcpatch.write(result, "boreholes.ifc")
+            result = ifcpatch.execute({"input": fn, "file": model, "recipe": "ExtractPropertiesToSQLite"})
+            ifcpatch.write(result, "output.sqlite")
        """
        self.file = file
        self.logger = logger
@@ -102,26 +102,13 @@ def clash(
    tolerance: float = 0.002,
    scope: str = "storey",
 ) -> dict[str, Any]:
-    """Check one element for geometric clashes against other elements.
-
-    Reports hard intersections and, optionally, violations of a required
-    clearance. Returns the overall ``pass``, the ``scope`` actually used, a
-    ``checks`` block in which each clash names the other ``element``, the
-    clash ``type``, the ``distance`` and the two closest points ``p1``/``p2``,
-    and a de-duplicated flat ``elements`` list of everything involved.
-    Geometry is computed for every element in scope, so this is slow on large
-    models; ``pass`` is ``None`` with an ``error`` when the element has no
-    usable geometry.
+    """Check element for geometric clashes against other elements.

    :param model: The IFC model.
    :param element: The element to check.
-    :param clearance: Minimum required clearance distance; when given, also
-        runs the clearance check alongside the intersection check.
+    :param clearance: Minimum clearance distance; if provided, runs clearance check.
    :param tolerance: Intersection tolerance in meters (default 0.002).
-    :param scope: ``"storey"`` (default) checks only elements sharing the
-        same spatial container; ``"all"`` checks every ``IfcElement``.
-        ``"storey"`` falls back to ``"all"`` when the element has no spatial
-        container.
+    :param scope: Which elements to check against: "storey" or "all".
    :return: Dict with clash results suitable for JSON serialization.
    """
    result: dict[str, Any] = {"element": _ref(element)}
@@ -26,19 +26,10 @@ def _cost_item_to_dict(item: ifcopenshell.entity_instance, max_depth: int | None


 def cost(model: ifcopenshell.file, max_depth: int | None = None) -> list[dict[str, Any]]:
-    """List the cost schedules: bills of quantities and their cost items.
+    """Return a list of IfcCostSchedule entries with nested cost item trees.

-    Covers ``IfcCostSchedule`` only — this is the money dimension of the
-    model; see ``schedule()`` in this module for the construction programme.
-    Each cost item reports its cost ``values`` as ``formula`` label and
-    ``category`` pairs, together with its nested ``subitems``. Returns an
-    empty list when the model has no cost schedules.
-
-    :param model: The in-memory IFC model.
-    :param max_depth: Levels of cost item nesting to expand, counting root
-        items as level 1. Past the cutoff ``subitems`` is replaced by a
-        ``{"truncated": True, "count": N}`` marker giving the number of items
-        not expanded. ``None`` (default) expands to unlimited depth.
+    max_depth limits how many levels of subitems are expanded (None = unlimited).
+    At the cutoff level, subitems is replaced with {"truncated": True, "count": N}.
    """
    result = []
    for cost_schedule in model.by_type("IfcCostSchedule"):
@@ -188,16 +188,7 @@ def _material_to_dict(material: ifcopenshell.entity_instance | None) -> dict[str


 def info(model: ifcopenshell.file, element: ifcopenshell.entity_instance) -> dict[str, Any]:
-    """Inspect a single entity in depth.
-
-    Returns the entity's direct ``attributes`` plus, where present,
-    ``property_sets``, ``element_type``, ``material``, ``container``,
-    ``placement`` and ``geometry_summary``. Keys are omitted when the
-    information is unavailable.
-
-    :param model: The in-memory IFC model.
-    :param element: The entity to inspect.
-    """
+    """Return deep inspection data for an element."""
    result: dict[str, Any] = {
        "id": element.id(),
        "type": element.is_a(),
@@ -22,13 +22,7 @@ import ifcopenshell


 def materials(model: ifcopenshell.file) -> list[dict]:
-    """List the materials and material sets defined in the model.
-
-    Returns a single list covering ``IfcMaterial`` (with its category),
-    ``IfcMaterialLayerSet`` (each layer's name, thickness, material and
-    ventilation flag), ``IfcMaterialConstituentSet`` (constituent names,
-    materials and fractions) and ``IfcMaterialProfileSet`` (profile names and
-    materials). Every entry carries the step ID of the material entity.
+    """Return all materials and material sets from the model.

    :param model: The in-memory IFC model.
    :return: List of dicts covering IfcMaterial, IfcMaterialLayerSet,
@@ -182,22 +182,7 @@ def _collect_elements(data: Any, seen: set[int], result: list[dict[str, Any]]) -
 def relations(
    model: ifcopenshell.file, element: ifcopenshell.entity_instance, traverse: str | None = None
 ) -> dict[str, Any] | list[dict[str, Any]]:
-    """Show how an element relates to the rest of the model.
-
-    By default returns a dict whose optional blocks are ``hierarchy`` (parent,
-    container, aggregate, nest, filled void, voided element), ``children``
-    (contained, parts, components, openings), ``type_relationship``,
-    ``groups``, ``systems``, ``zones``, ``material``, ``referenced_structures``
-    and ``connections`` (connected to/from, ports), plus a de-duplicated flat
-    ``elements`` list of everything referenced. Blocks with nothing to report
-    are omitted.
-
-    :param model: The IFC model.
-    :param element: The element to examine.
-    :param traverse: Set to ``'up'`` to instead return the chain of ancestors
-        from the element to ``IfcProject`` as a flat list. Any other value
-        gives the default behaviour.
-    """
+    """Return relationships for an element, or hierarchy chain if traverse='up'."""
    if traverse == "up":
        return _traverse_up(element)
    result = _all_relations(model, element)
@@ -37,20 +37,10 @@ def _task_to_dict(task: ifcopenshell.entity_instance, max_depth: int | None, dep


 def schedule(model: ifcopenshell.file, max_depth: int | None = None) -> list[dict[str, Any]]:
-    """List the construction programme: work schedules and their task trees.
+    """Return a list of IfcWorkSchedule entries with nested task trees.

-    Covers ``IfcWorkSchedule`` only — this is the time dimension of the
-    model; see ``cost()`` in this module for the money dimension. Each
-    schedule lists its tasks recursively, and each task carries its scheduled
-    ``start`` and ``finish``, an ``is_milestone`` flag, the products it
-    ``outputs`` and its ``subtasks``. Returns an empty list when the model has
-    no work schedules.
-
-    :param model: The in-memory IFC model.
-    :param max_depth: Levels of subtask nesting to expand, counting root tasks
-        as level 1. Past the cutoff ``subtasks`` is replaced by a
-        ``{"truncated": True, "count": N}`` marker giving the number of tasks
-        not expanded. ``None`` (default) expands to unlimited depth.
+    max_depth limits how many levels of subtasks are expanded (None = unlimited).
+    At the cutoff level, subtasks is replaced with {"truncated": True, "count": N}.
    """
    result = []
    for work_schedule in model.by_type("IfcWorkSchedule"):
@@ -8,15 +8,7 @@ import ifcopenshell.util.doc


 def schema(model: ifcopenshell.file, entity_type: str) -> dict[str, Any]:
-    """Look up the IFC documentation for an entity class.
-
-    Returns the class ``description``, its ``predefined_types``, per-attribute
-    documentation and a ``spec_url``, resolved against the model's schema
-    version. Returns an ``error`` key for an unknown class.
-
-    :param model: The in-memory IFC model, used only for its schema version.
-    :param entity_type: IFC class name, for example ``'IfcWall'``.
-    """
+    """Return IFC class documentation for entity_type from model's schema version."""
    schema_name = model.schema
    try:
        doc = ifcopenshell.util.doc.get_entity_doc(schema_name, entity_type)
@@ -26,15 +26,7 @@ import ifcopenshell


 def summary(model: ifcopenshell.file) -> dict[str, Any]:
-    """Summarise the model: schema, entity counts and project info.
-
-    Returns the ``schema`` version, ``total_entities``, and a ``project``
-    block with the id, name and description of the first ``IfcProject``
-    (omitted if the model has none). The count covers every entity in the
-    file, not just physical elements.
-
-    :param model: The in-memory IFC model.
-    """
+    """Return a model overview with schema, element counts, and project info."""
    # Count elements by IFC type, sorted by count descending
    type_counter: Counter[str] = Counter()
    total = 0
@@ -59,17 +59,7 @@ def _build_spatial_node(element: ifcopenshell.entity_instance) -> dict[str, Any]


 def tree(model: ifcopenshell.file) -> dict[str, Any] | list[dict[str, Any]]:
-    """Return the spatial hierarchy of the model as a nested tree.
-
-    Starts at ``IfcProject`` and descends through decomposition (site,
-    building, storeys) and containment (the elements placed in each storey).
-    Every node carries ``id``, ``type`` and ``name``; ``children`` holds
-    decomposed sub-spaces and ``elements`` holds contained elements, and
-    either key is omitted when empty. Returns a list when the file contains
-    several projects, or an ``error`` key when it contains none.
-
-    :param model: The in-memory IFC model.
-    """
+    """Return the spatial hierarchy tree starting from IfcProject."""
    projects = model.by_type("IfcProject")
    if not projects:
        return {"error": "No IfcProject found in model"}
@@ -8,16 +8,7 @@ import ifcopenshell.validate


 def validate(model: ifcopenshell.file, express_rules: bool = False) -> dict[str, Any]:
-    """Validate the model against the IFC schema.
-
-    Returns ``valid`` together with a list of ``issues``, each carrying a
-    ``level`` and a ``message``. Worth running after a batch of edits and
-    before writing the model back to disk.
-
-    :param model: The in-memory IFC model.
-    :param express_rules: Also evaluate the schema's EXPRESS rules. Catches
-        more problems but is considerably slower (default ``False``).
-    """
+    """Validate the model and return a dict with 'valid' bool and 'issues' list."""
    logger = ifcopenshell.validate.json_logger()
    ifcopenshell.validate.validate(model, logger, express_rules=express_rules)
    issues = [{"level": s["level"], "message": s["message"]} for s in logger.statements]