fix(ezdxf): block_insert with attributes referenced an anonymous *U block and lost its ATTRIBs

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd

backends/ezdxf_backend.py

@@ -4453,12 +4453,13 @@ class EzdxfBackend(AutoCADBackend):
             }
             if layer:
                 attribs["layer"] = layer
+            ref = msp.add_blockref(name, (float(x), float(y)), dxfattribs=attribs)
             if attributes:
-                ref = msp.add_auto_blockref(
-                    name, (float(x), float(y)), attributes, dxfattribs=attribs
-                )
-            else:
-                ref = msp.add_blockref(name, (float(x), float(y)), dxfattribs=attribs)
+                # `add_auto_blockref` wraps the INSERT in an anonymous *U block,
+                # so the returned handle names `*U1` and carries no ATTRIBs.
+                # `add_auto_attribs` attaches ATTRIBs to this INSERT for every
+                # ATTDEF the definition has; values for tags it lacks are ignored.
+                ref.add_auto_attribs({str(k): str(v) for k, v in attributes.items()})
             self._mark_dirty()
             return _entity_info_dxf(ref)
 

tests/test_block_insert_attributes.py

@@ -0,0 +1,43 @@
+"""block_insert(attributes=...) must reference the named block, not an anonymous wrapper.
+
+ezdxf's `add_auto_blockref` wraps the INSERT in an anonymous `*U` block. The
+handle it returns then reports block_name `*U1`, and `block_get_attributes`
+finds no ATTRIBs on it — an insert with attributes silently lost them.
+"""
+
+from __future__ import annotations
+
+import pytest
+
+pytestmark = pytest.mark.asyncio
+
+
+def _define_tagged_block(backend, name: str = "TB") -> None:
+    blk = backend._doc.blocks.new(name=name)
+    blk.add_line((0, 0), (10, 0))
+    blk.add_attdef("TAG", insert=(0, 3), text="", dxfattribs={"height": 2.5})
+
+
+async def test_insert_with_attributes_references_the_named_block(backend):
+    _define_tagged_block(backend)
+    ref = await backend.block_insert("TB", 10, 10, attributes={"TAG": "P-101"})
+
+    info = await backend.entity_get(ref.handle)
+    assert info.properties["block_name"] == "TB"
+    assert await backend.block_get_attributes(ref.handle) == {"TAG": "P-101"}
+    anonymous = [b.name for b in backend._doc.blocks if b.name.startswith("*U")]
+    assert anonymous == [], "no anonymous wrapper block may be created"
+
+
+async def test_insert_ignores_values_for_tags_the_block_does_not_define(backend):
+    _define_tagged_block(backend)
+    ref = await backend.block_insert("TB", 0, 0, attributes={"TAG": "V-1", "NOPE": "x"})
+    assert await backend.block_get_attributes(ref.handle) == {"TAG": "V-1"}
+
+
+async def test_insert_without_attributes_is_unchanged(backend):
+    _define_tagged_block(backend)
+    ref = await backend.block_insert("TB", 0, 0)
+    info = await backend.entity_get(ref.handle)
+    assert info.properties["block_name"] == "TB"
+    assert await backend.block_get_attributes(ref.handle) == {}