# Feature: Extract Tests to `tests/` Directory ✅ COMPLETED
**Status**: Completed 2025-12-21
**Original Location**: docs/features/TEST_FILE_EXTRACTION.md
## Summary
All inline `#[cfg(test)] mod tests` blocks were extracted from source files into dedicated test files in the `tests/` directory.
## Final Test Distribution
| `tests/parser_edge_cases_test.rs` | 83 | Moved from `src/parser/edge_case_tests.rs` |
| `tests/parser_unit_test.rs` | 41 | Extracted from `src/parser/mod.rs`, `mysql_insert.rs`, `postgres_copy.rs` |
| `tests/convert_unit_test.rs` | 23 | Extracted from `src/convert/mod.rs`, `types.rs`, `copy_to_insert.rs`, `warnings.rs` |
| `tests/schema_unit_test.rs` | 19 | Extracted from `src/schema/mod.rs`, `ddl.rs`, `graph.rs` |
| `tests/sample_integration_test.rs` | 15 | Already in tests/ |
| `tests/convert_integration_test.rs` | 15 | Already in tests/ |
| `tests/sample_unit_test.rs` | 13 | Extracted from `src/sample/mod.rs`, `config.rs`, `reservoir.rs` |
| `tests/splitter_unit_test.rs` | 7 | Extracted from `src/splitter/mod.rs` |
| `tests/shard_unit_test.rs` | 7 | Extracted from `src/shard/mod.rs`, `config.rs` |
| `tests/cmd_unit_test.rs` | 5 | Extracted from `src/cmd/merge.rs` |
| `tests/merger_unit_test.rs` | 3 | Extracted from `src/merger/mod.rs` |
| `tests/writer_unit_test.rs` | 2 | Extracted from `src/writer/mod.rs` |
| `tests/analyzer_unit_test.rs` | 2 | Extracted from `src/analyzer/mod.rs` |
| **Total** | **235** | |
## Results
- ✅ **0 inline tests** remain in `src/` directory
- ✅ **235 tests** pass across 13 test files
- ✅ **All source files** now contain only production code
- ✅ **Build succeeds** in both debug and release mode
## Benefits Achieved
1. **Complete separation** - Production code contains zero test code
2. **Cleaner source files** - `src/` only contains business logic
3. **Single test location** - All tests discoverable in `tests/` directory
4. **API-focused testing** - Tests use public interfaces
5. **Consistent organization** - Matches common Rust project patterns
## Notes
- Some tests that accessed private functions were rewritten to use public APIs
- A few functions were made `pub` to enable testing (e.g., `split_table_body`, `parse_column_list`)
- 2 tests in `src/shard/mod.rs` were left as they test truly private helper functions