Fix all ty diagnostics on ifcviewer-wgpu (ci-lint ty-ios + ty-bonsai)

This branch carried v0.8.0's strict `[tool.ty.rules] all = "error"` config but
not the source fixes that were made upstream to satisfy it, so both ci-lint ty
gates were failing: `poe ty-ios` reported 256 diagnostics and `poe ty-bonsai`
258. Both are now clean.

Most fixes are ported from v0.8.0 and follow two idioms: initialise a name
before a conditional that may not bind it (plus an `assert` where the invariant
is real but not provable), and close an exhaustive `if`/`elif` chain with
`else: assert False, <discriminant>`.

The branch's own newer accessors are preserved throughout - `.file`,
`.declaration`, `file.types()`, `get_max_id()` are kept rather than reverted to
`wrapped_data.*`, and non-ty upstream changes (notably the in-progress geometry
cache removal) are deliberately not pulled in.

Notable fixes that are not straight ports:

* ifcopenshell_wrapper.pyi: `entity_instance.file` was declared as
  `def file(self) -> file`, where the property name shadows the `class file`
  below it, so the annotation resolved to `Unknown`. Every `element.file` in
  the codebase was therefore unchecked. Qualifying it to `ifcopenshell.file`
  restores `.schema` to its Literal union and surfaces no new diagnostics.

* model/wall.py: a duplicated merge fragment in the void-straddle path ran an
  always-true `if void_straddles:` that read `new_opening` from the mutually
  exclusive branch (stale value, or NameError on the first iteration), followed
  by an unreachable duplicate `elif`. Removing it makes the file match v0.8.0.

* light/operator.py: upstream's own fix unpacks three targets from two values
  and raises ValueError unconditionally; corrected to `None, None, None`.

* assign_system.py, validate.py, geom/main.py: walrus-in-genexp is valid at
  runtime (PEP 572 binds in the containing scope) but ty does not model it;
  rewritten as explicit loops, matching upstream.

Verified: poe ty-ios, poe ty-bonsai, ruff check src/ nix/, black --check .,
and compileall -W error at py3.10 (ifcopenshell-python) and py3.11 (bonsai).

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/ifcopenshell-python/ifcopenshell/util/cost.py

@@ -112,6 +112,8 @@ def sum_child_root_elements(root_element: ifcopenshell.entity_instance, category
                 values = new_child_root_element.CostValues
             elif root_element.is_a("IfcConstructionResource"):
                 values = child_root_element.BaseCosts
+            else:
+                assert False, root_element
             for child_cost_value in values or []:
                 if category_filter and child_cost_value.Category != category_filter:
                     continue

src/ifcopenshell-python/ifcopenshell/util/element.py

@@ -331,6 +331,8 @@ def get_quantity(
             data["properties"] = get_quantities(quantity.HasQuantities, verbose=verbose)
             del data["HasQuantities"]
             result = data
+        else:
+            assert False, quantity
         if verbose:
             result = {"id": quantity.id(), "class": quantity.is_a(), "value": result}
         return result
@@ -387,6 +389,7 @@ def get_property(
         if prop.Name != name:
             continue
         is_single_value = False  # For now we pass value type only for single values.
+        result_type = None
         if prop.is_a("IfcPropertySingleValue"):
             # 2 IfcPropertySingleValue.NominalValue
             result = v.wrappedValue if (v := prop[2]) else None
@@ -409,6 +412,8 @@ def get_property(
             data["properties"] = get_properties(prop.HasProperties, verbose=verbose)
             del data["HasProperties"]
             result = data
+        else:
+            assert False, prop
         if verbose:
             result = {"id": prop.id(), "class": prop.is_a(), "value": result}
             if is_single_value:

src/ifcopenshell-python/ifcopenshell/util/geolocation.py

@@ -260,6 +260,8 @@ def get_helmert_transformation_parameters(ifc_file: ifcopenshell.file) -> Option
             xaa = 1.0
             xao = 0.0
             scale = factor_x = factor_y = factor_z = 1
+        else:
+            assert False, conversion
 
     if not xaa and not xao:
         xaa = 1.0

src/ifcopenshell-python/ifcopenshell/util/mvd_info.py

@@ -18,18 +18,16 @@
 
 from __future__ import annotations
 
-try:
-    from lark import Lark, Transformer
-    from lark.exceptions import UnexpectedCharacters, UnexpectedEOF, UnexpectedToken
-
-    LARK_AVAILABLE = True
-except ImportError:
-    LARK_AVAILABLE = False
-
+import importlib.util
 import re
 from typing import Union
 
+LARK_AVAILABLE = importlib.util.find_spec("lark") is not None
+
 if LARK_AVAILABLE:
+    from lark import Lark, Transformer
+    from lark.exceptions import UnexpectedCharacters, UnexpectedEOF, UnexpectedToken
+
     mvd_grammar = r"""
         start: entry+
 
@@ -92,9 +90,9 @@ if LARK_AVAILABLE:
                 self.store_text_attribute(args, "options")
 
         def dynamic_option(self, args):
+            original_keyword = str(args[0])
+            key = original_keyword.lower()
             try:
-                original_keyword = str(args[0])
-                key = original_keyword.lower()
                 raw_text = args[1].children[0].value
                 parsed_value = parse_semicolon_separated_kv(raw_text)
                 self._dynamic[key] = (parsed_value, original_keyword)

src/ifcopenshell-python/ifcopenshell/util/placement.py

@@ -89,6 +89,9 @@ def get_axis2placement(placement: ifcopenshell.entity_instance) -> MatrixType:
         x = np.array((1, 0, 0))
         o = placement.Location.Coordinates
 
+    else:
+        assert False, placement
+
     return a2p(o, z, x)
 
 

src/ifcopenshell-python/ifcopenshell/util/schema.py

@@ -569,6 +569,7 @@ class Migrator:
         # NOTE: `attribute` is an attribute in new file schema
         # print("Migrating attribute", element, new_element, attribute.name())
         old_file = element.file
+        value = ...
         if hasattr(element, attribute.name()):
             value = getattr(element, attribute.name())
             # print("Attribute names matched", value)
@@ -607,9 +608,7 @@ class Migrator:
             except:  # We tried our best
                 return
 
-        try:
-            value
-        except UnboundLocalError:
+        if value is ...:
             print(
                 f"Couldn't match attribute {attribute.name()} by name to migrate from {element} "
                 f"to {new_element} and there is no special mapping to handle migration "

src/ifcopenshell-python/ifcopenshell/util/selector.py

@@ -1290,6 +1290,8 @@ class FacetTransformer(lark.Transformer):
             result = bool(value.match(element_value)) if element_value is not None else False
         elif value in (None, True, False):
             result = element_value is value
+        else:
+            assert False, value
 
         if comparison.startswith("!"):
             return not result

src/ifcopenshell-python/ifcopenshell/util/shape_builder.py

@@ -210,6 +210,8 @@ def np_rotation_matrix(
             matrix = np.array([[cos_theta, 0, sin_theta], [0, 1, 0], [-sin_theta, 0, cos_theta]])
         elif axis == "Z":
             matrix = np.array([[cos_theta, -sin_theta, 0], [sin_theta, cos_theta, 0], [0, 0, 1]])
+        else:
+            assert False, axis
     else:
         # Assume axis is a vector.
         axis = axis / np.linalg.norm(axis)
@@ -473,7 +475,6 @@ class ShapeBuilder:
         if arc_points and self.file.schema == "IFC2X3":
             raise Exception("Arcs are not supported for IFC2X3.")
 
-        points: np.ndarray
         points = np.array(points)
         if position_offset is not None:
             points = points + position_offset
@@ -635,7 +636,6 @@ class ShapeBuilder:
         diff = (0.01, 0.01) * diff_sign
         middle_point = points[0] + diff
 
-        points: list[VectorType]
         points = [points[0], middle_point, points[1]]
         points = [ifc_safe_vector_type(p) for p in points]
         seg = self.file.createIfcArcIndex((1, 2, 3))