fix: make box() parameter names consistent with Workplane.box and Solid.makeBox

cadquery/assembly.py

@@ -627,6 +627,33 @@ def export(
 
         return self
 
+    def toBOM(
+        self, indent: int = 0, _result: Optional[List[Dict[str, Any]]] = None,
+    ) -> List[Dict[str, Any]]:
+        """
+        Generate a Bill of Materials (BOM) for this assembly.
+
+        Returns a flat list of dictionaries, one per component, with fields:
+        - name: component name
+        - level: nesting depth (0 = root)
+        - has_shape: whether the component has geometry
+
+        :param indent: current nesting level (used internally for recursion)
+        :return: list of BOM line items
+        """
+
+        if _result is None:
+            _result = []
+
+        _result.append(
+            {"name": self.name, "level": indent, "has_shape": self.obj is not None,}
+        )
+
+        for child in self.children:
+            child.toBOM(indent=indent + 1, _result=_result)
+
+        return _result
+
     @classmethod
     def importStep(cls, path: str, unit: UnitLiterals = "MM") -> Self:
         """

cadquery/occ_impl/shapes.py

@@ -6553,14 +6553,23 @@ def plane() -> Face:
     return _shape(BRepBuilderAPI_MakeFace(pln_geom, -INF, INF, -INF, INF).Face(), Face)
 
 
-def box(w: float, l: float, h: float) -> Solid:
+def box(length: float, width: float, height: float) -> Solid:
     """
-    Construct a solid box.
+    Construct a solid box centered on the XY plane.
+
+    :param length: box size along the X axis
+    :param width: box size along the Y axis
+    :param height: box size along the Z axis
     """
 
     return _shape(
         BRepPrimAPI_MakeBox(
-            gp_Ax2(Vector(-w / 2, -l / 2, 0).toPnt(), Vector(0, 0, 1).toDir()), w, l, h
+            gp_Ax2(
+                Vector(-length / 2, -width / 2, 0).toPnt(), Vector(0, 0, 1).toDir(),
+            ),
+            length,
+            width,
+            height,
         ).Shape(),
         Solid,
     )

tests/test_assembly.py

@@ -2603,3 +2603,21 @@ def test_name_geometries(tmpdir):
     assert len([l for l in lines if "top_face" in l]) == 2
     assert len([l for l in lines if "plane_" in l]) == 2
     assert len([l for l in lines if "seg_" in l]) == 3
+
+
+def test_toBOM():
+
+    assy = cq.Assembly(name="root")
+    assy.add(box(1, 1, 1), name="part1")
+
+    subassy = cq.Assembly(name="sub")
+    subassy.add(box(2, 2, 2), name="part2")
+    assy.add(subassy, name="sub")
+
+    bom = assy.toBOM()
+
+    assert len(bom) == 4
+    assert bom[0] == {"name": "root", "level": 0, "has_shape": False}
+    assert bom[1] == {"name": "part1", "level": 1, "has_shape": True}
+    assert bom[2] == {"name": "sub", "level": 1, "has_shape": False}
+    assert bom[3] == {"name": "part2", "level": 2, "has_shape": True}