Add a process-global `_INITIALIZED_DBS: set[str]` to `features/environment.py` that caches database URLs after `_fast_init_or_upgrade` has processed them. On subsequent calls with the same URL, the function returns immediately — skipping all URL parsing, path extraction, prefix matching, and `stat()` syscalls that previously executed on every new `UnitOfWork` instance.
The cache is cleared at the start of each scenario in `before_scenario` to prevent cross-scenario state leaks, since each scenario receives fresh temp-DB paths via `tempfile.mktemp()`.
Four new Behave scenarios validate cache hits on repeated calls, cache clearing between scenarios, and non-caching of non-matching-prefix URLs.
Estimated savings: ~65,000 unnecessary function-body executions eliminated per full test run (~7 UnitOfWork instantiations × ~10,700 scenarios).
ISSUES CLOSED: #735
Reviewed-by: Jeffrey Phillips Freeman <jeffrey.freeman@cleverthis.com>
Co-authored-by: Brent E. Edwards <brent.edwards@cleverthis.com>
Co-committed-by: Brent E. Edwards <brent.edwards@cleverthis.com>
Add 8 BDD scenarios in features/fast_init_upgrade.feature that directly
exercise the _fast_init_or_upgrade closure installed by
_install_template_db_patch in features/environment.py.
Scenarios cover all code paths:
- Non-empty DB with matching prefix → early return (original NOT invoked)
- Non-existent DB with matching prefix → template copied (original NOT invoked)
- Existing empty DB with matching prefix → template copied (original NOT invoked)
- Non-matching prefix → delegates to original init_or_upgrade
- In-memory SQLite → delegates to original init_or_upgrade
- Non-SQLite URL → delegates to original init_or_upgrade
- Bare sqlite:// URL → delegates to original init_or_upgrade
- Delegation forwards runner instance and keyword arguments correctly
Test infrastructure:
- features/mocks/fast_init_test_helpers.py provides a context manager
(patch_original_init_or_upgrade) that replaces the _original_init_or_upgrade
reference inside the closure via cell_contents manipulation, enabling
precise call-tracking without recreating the function under test.
- All scenarios tagged @mock_only to skip unnecessary DB setup.
- Cleanup registered via context._cleanup_handlers for temp file removal.
- Works in both sequential and parallel execution modes.
Review fix round:
- Added bare sqlite:// URL scenario covering the second branch of the
in-memory disjunction (L1).
- Added scenario verifying runner instance and keyword argument forwarding
through the delegation path (L2, L3).
- Replaced hardcoded test credentials with clearly synthetic pattern (I4).
- Fixed CHANGELOG wording that incorrectly claimed mktemp replacement (L5).
ISSUES CLOSED: #733
brent.edwards
CoreRasurae
