## Summary
- **Use `Tester` as fixture base** for all test suites that need
compilation, replacing `TesterFixture` and removing redundant
`tester.clear()` calls (eventide zest now creates fresh instances per
TEST_CASE)
- **Remove local `Tester` variables** in `compilation_tests`,
`template_resolver_tests`, `selection_tests` — use inherited fixture
members directly
- **Normalize helper naming**: `expect_xxx` → `EXPECT_XXX`,
`go_to_definition` → `GO_TO_DEFINITION` for consistency
- **Extract shared `test/cdb_helper.h`**: deduplicate `CDBEntry`,
`json_escape`, `build_cdb_json` from `dependency_graph_tests` and
`compile_graph_integration_tests`
- **Add new test files/cases**: `project_index_tests.cpp`, expanded
`tu_index_tests`, `merged_index_tests`, `compilation_tests`
## Test plan
- [x] All existing unit tests pass
- [x] New index tests (TUIndex, MergedIndex, ProjectIndex) pass
- [x] Compilation tests (PCH, PCM, stop) pass
🤖 Generated with [Claude Code](https://claude.com/claude-code)
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## Summary by CodeRabbit
* **Tests**
* Standardized test fixtures and helper naming, moved suites to a shared
fixture, and unified in-memory VFS and compile flows.
* Added broad new coverage: indexing, project indexing, compilation/PCH,
diagnostics, semantic features, and many targeted unit cases.
* Introduced a small compile-database helper and improved driver-style
test compilation paths.
* **Chores**
* Consolidated and reorganized test utilities and tester APIs for easier
maintenance and reuse.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
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Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>