Route _has_material_styles through tool.Root.has_material_styles

Pre-existing architectural smell on v0.8.0: core/root.py.copy_class
called a module-level _has_material_styles helper that did
ifcopenshell.util.element.get_materials() directly, bypassing the
Prophecy mock seam that every other branch in copy_class flowed
through. Symptom: test/core/test_root.py::TestCopyClass::
test_AAAAAAAAAAAA passed mock strings into copy_class, the helper
called .is_a() on the string, AttributeError.

Move the check to tool.Root.has_material_styles (paired with
assign_body_styles — they're called in sequence as "is there a
material style? if not, assign body style"). core/root.py now
calls root.has_material_styles(new) like every other dependency,
fixing the test failure and dropping the ifcopenshell.util.element
import that was the only consumer of the ifcopenshell import at
module load in core/root.py.

* core/tool.py: add abstract has_material_styles to Root interface.
* tool/root.py: add concrete classmethod near assign_body_styles.
* core/root.py: replace _has_material_styles helper call site with
  root.has_material_styles; drop the local helper and its import.
* test/core/test_root.py: add the new mock expectation
  root.has_material_styles("element").will_return(False) before the
  existing assign_body_styles expectation.

Generated with the assistance of an AI coding tool.

src/bonsai/bonsai/core/root.py

@@ -20,8 +20,6 @@ from __future__ import annotations
 
 from typing import TYPE_CHECKING, Optional
 
-import ifcopenshell.util.element
-
 if TYPE_CHECKING:
     import bpy
     import ifcopenshell
@@ -58,31 +56,12 @@ def copy_class(
             geometry.change_object_data(obj, data, is_global=True)
             geometry.rename_object(data, geometry.get_representation_name(ifc.get_entity(data)))
         # Only assign styles if element doesn't get them from material
-        if not _has_material_styles(ifc, new):
+        if not root.has_material_styles(new):
             root.assign_body_styles(new, obj)
     collector.assign(obj)
     return new
 
 
-def _has_material_styles(ifc: type[tool.Ifc], element: ifcopenshell.entity_instance) -> bool:
-    """Check if element has styles defined through its material.
-
-    Returns True if any constituent material has a style representation,
-    which means styles should NOT be applied directly to the geometry.
-    """
-    materials = ifcopenshell.util.element.get_materials(element)
-
-    if not materials:
-        return False
-
-    # Check if any of the constituent materials have styles
-    for material in materials:
-        if hasattr(material, "HasRepresentation") and material.HasRepresentation:
-            return True
-
-    return False
-
-
 def assign_class(
     ifc: type[tool.Ifc],
     collector: type[tool.Collector],

src/bonsai/bonsai/core/tool.py

@@ -884,6 +884,7 @@ class Root:
     def get_object_name(cls, obj): pass
     def get_object_representation(cls, obj): pass
     def get_representation_context(cls, representation): pass
+    def has_material_styles(cls, element): pass
     def is_containable(cls, element): pass
     def is_drawing_annotation(cls, element): pass
     def is_element_a(cls, element, ifc_class): pass

src/bonsai/bonsai/tool/root.py

@@ -71,6 +71,18 @@ class Root(bonsai.core.tool.Root):
                 should_use_presentation_style_assignment=props.should_use_presentation_style_assignment,
             )
 
+    @classmethod
+    def has_material_styles(cls, element: ifcopenshell.entity_instance) -> bool:
+        """``True`` if any constituent material on ``element`` carries a style
+        representation. Body styles should NOT be applied directly when this
+        is True — the material-inherited style is the authoritative source.
+        Paired with ``assign_body_styles``: callers check this first and only
+        call ``assign_body_styles`` when it returns False."""
+        materials = ifcopenshell.util.element.get_materials(element)
+        if not materials:
+            return False
+        return any(getattr(m, "HasRepresentation", None) for m in materials)
+
     @classmethod
     def copy_representation(
         cls, source: ifcopenshell.entity_instance, dest: ifcopenshell.entity_instance

src/bonsai/test/core/test_root.py

@@ -56,6 +56,7 @@ class TestCopyClass:
         ifc.get_entity("data").should_be_called().will_return("new_representation")
         geometry.get_representation_name("new_representation").should_be_called().will_return("name")
         geometry.rename_object("data", "name").should_be_called()
+        root.has_material_styles("element").should_be_called().will_return(False)
         root.assign_body_styles("element", "obj").should_be_called()
         collector.assign("obj").should_be_called()
         subject.copy_class(ifc, collector, geometry, root, obj="obj")