Three blocking review findings in engineering/mech/annotate.py.
1. draw_annotation_prims assigned ROLE_LAYER[role] without creating the
layer. EzdxfBackend._apply_attrs adds a missing layer; ActiveX does not.
MEASURED live on AutoCAD 2026 (probe: GetActiveObject, Documents.Add(),
doc.Close(False) in finally): on a scratch document whose layer table is
['0'], draw_surface_texture(ComBackend(), at=(0,0), ra=3.2,
machining='required', lay='perpendicular', allowance=0.5) raised
"AutoCAD COM error (-0x7ffdfff7)" and left one orphan AcDbLine on layer 0
— a partial write with no rollback, on exactly the foreign-drawing path
the spec names (drawing_open runs no bootstrap). The same probe after the
fix: {'ok': True, count 6, 'layers_created': ['DIM','TEXT']}, model space
['AcDbLine' x4 on DIM, 'AcDbText' x2 on TEXT], layer table ['0','DIM',
'TEXT']. New helper ensure_annotation_layers() creates every target layer
up front, before the first entity, with its ENGINEERING_LAYERS colour /
linetype / lineweight; the result reports layers_created.
2. side='both' drew the two elementary symbols 0.4h apart — the other-side
one still stood on the (correctly omitted) identification line, so a
double-V butt weld came out as two detached halves that were not even
symmetric about the reference line. ISO 2553 places them back-to-back on
the continuous reference line: the other-side baseline is now 0.0 when
there is no identification line. tests/test_mech_annotate.py asserted the
wrong apex (-0.4*h), so the gate certified the defect; that test is
rewritten to assert the mirror pair, plus a double-fillet case.
3. For side='other' the size and length were written above the reference
line while the symbol hung below the identification line — 'a6' sat where
an arrow-side throat dimension sits, on a joint with no arrow-side weld.
Both texts now sit beside their own symbol (0.25h clear of the line it
stands on, on the symbol's side). New test covers side='other' with size
and length, and pins arrow/both unchanged.
All five new or rewritten tests fail against the pre-fix module (the layer
one with the measured 'Key not found' refusal, via a fake that models only
that measured behaviour) and pass after. tests/test_mech_annotate.py: 29
passed. Full suite: 3326 passed, 6 pre-existing failures unrelated to this
change (verified identical on the branch tip with the change stashed),
test_release_consistency.py::test_document_numbers_match_the_tree
deselected as instructed. No tool registration changed, so
docs/tool-inventory.json regenerates byte-identical.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd
