[SizzleUnrlsd]

Summary

Follow-up to #274. With Plugin.rules, a plugin describes the rules it reports, and the SARIF report passes the descriptions to its consumers. A check, however, gathered them only from the plugins it loaded from plugin roots. A plugin given to analyze_project as an instance (plugins=[...]) still reported its findings, but its rules reached the report by id alone.

The descriptions now come from every plugin of the check, in this order: the engine's own rules, then the loaded plugins', then those of the plugins given as instances. When several declare the same id, the first declaration is kept.

Commit	Change
fix(engine): describe the rules of plugins given as instances	rule_descriptions takes the plugins of the check instead of the registry; the test of an instance's rule
test(rules): keep a loaded plugin's description of a rule an instance describes too	the order of precedence

Tests

The new file tests/test_rule_descriptions_of_given_plugins.py holds 2 tests. Before the fix:

• the first fails with KeyError: 'quiet-rule';
• the second passes, and pins the existing order.

No existing test changes.

Compatibility

engine.rule_descriptions now takes plugins instead of a PluginRegistry. Nothing calls it outside engine.py, in this repository or in the Enterprise plugins. Plugin.rules is not released yet, so the changelog entry of #274 covers this.

Verification

Python 3.12, on main at 8e9e944:

• ruff check . and mypy: clean on each commit;
• unit suite: 2,575 passed on the first commit, 2,576 on the second;
• regression: 19 of 19;
• Enterprise plugins: 978 passed.