Phase 11.3.2. CONTEXT-MANAGER EXCEPTION.
The plan claimed 'StartupProfiler.phase() is NOT a context manager;
tier-2's claim is factually wrong.' This is incorrect. phase() IS a
context manager:
- Decorated with @contextmanager (src/startup_profiler.py:26)
- Used in 13 'with startup_profiler.phase(...)' call sites in
src/gui_2.py (lines 308, 311, 327, 338, 343, 627, 629, 631, 669,
672, 711, 729, 739)
It cannot return Result[None] because:
- @contextmanager requires the function to yield (not return)
- The except body is inside a finally block (which cannot return)
Best partial migration: extract _log_phase_output helper that returns
Result[None]; phase() calls it and ignores the Result (we're in a
finally block).
Audit post-migration:
- _log_phase_output L28 = INTERNAL_COMPLIANT (Heuristic A) ✓
- phase() L54 try/finally = INTERNAL_COMPLIANT (canonical cleanup) ✓
Tests: 12/12 pass (test_audit_allowlist_2d, test_gui_startup_smoke,
test_headless_service, test_startup_profiler, test_warmup_canaries).
This site is documented in the per-site report as a CONTEXT-MANAGER
EXCEPTION. The Heuristic #19 (catch+log) classification remains valid;
the partial migration adds explicit Result-returning helpers where
possible without breaking the context manager pattern.
ed
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