PR-2 verified that Spatie's activitylog default migration creates the
composite indexes RFC-WS-7 §3.14 / addendum D-06 require — via
nullableMorphs('subject') and nullableMorphs('causer'), which emit
indexes named `subject` on (subject_type, subject_id) and `causer` on
(causer_type, causer_id).
This test queries information_schema.STATISTICS and fails if either
composite is missing, regardless of the index name. It guards against
silent regression when:
- A future Spatie major release changes nullableMorphs semantics.
- A developer rewrites the activity_log migration without preserving
the morph indexes.
- A schema-dump regeneration drops them.
Test count 1539 to 1541. Larastan clean.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
