# Phase 5: Test Synchronization

**Role**: QA engineer and developer
**Goal**: Reconcile the test suite with the refactored codebase — remove obsolete tests, update broken tests, add tests for new code
**Constraints**: All tests must pass at the end of this phase. Do not change production code here — only tests.

**Skip condition**: If the run name contains `testability`, skip Phase 5 entirely — no test suite exists yet to synchronize. Proceed directly to Phase 6.

## 5a. Identify Obsolete Tests

1. Compare the pre-refactoring codebase structure (from Phase 0 inventory) with the current state
2. Find tests that reference removed functions, classes, modules, or endpoints
3. Find tests that duplicate coverage due to merged/consolidated code
4. Decide per test: **delete** (functionality removed) or **merge** (duplicates)

Write `RUN_DIR/test_sync/obsolete_tests.md`:
- Test file, test name, reason (target removed / target merged / duplicate coverage), action taken (deleted / merged into)

## 5b. Update Existing Tests

1. Run the full test suite — collect failures and errors
2. For each failing test, determine the cause:
   - Renamed/moved function or module → update import paths and references
   - Changed function signature → update call sites and assertions
   - Changed behavior (intentional per refactoring plan) → update expected values
   - Changed data structures → update fixtures and assertions
3. Fix each test, re-run to confirm it passes

Write `RUN_DIR/test_sync/updated_tests.md`:
- Test file, test name, change type (import path / signature / assertion / fixture), description of update

## 5c. Add New Tests

1. Identify new code introduced during Phase 4 that lacks test coverage:
   - New public functions, classes, or modules
   - New interfaces or abstractions introduced during decoupling
   - New error handling paths
2. Write tests following the same patterns and conventions as the existing test suite
3. Ensure coverage targets from Phase 3 are maintained or improved

Write `RUN_DIR/test_sync/new_tests.md`:
- Test file, test name, target function/module, coverage type (unit / integration / blackbox)

**Self-verification**:
- [ ] All obsolete tests removed or merged
- [ ] All pre-existing tests pass after updates
- [ ] New code from Phase 4 has test coverage
- [ ] Overall coverage meets or exceeds Phase 3 baseline (75% overall, 90% critical paths)
- [ ] No tests reference removed or renamed code

**Save action**: Write test_sync artifacts; implemented tests go into the project's test folder

**GATE (BLOCKING)**: ALL tests must pass before proceeding to Phase 6. If tests fail, fix the tests or ask user for guidance.