Many plan cache tests issue queries and then use $planCacheStats to examine the contents of the cache. Many of these are simple queries (single equality predicate) that qualify for the newly introduced CQF fast path (SERVER-82171). The fast path does not add plans to the cache nor does it consult the cache to get plans, causing many tests to fail which expect certain cache entries to be present. Since these test assume simple queries end up in the cache, but the fast path prevents this, I think we should disable the fast path for these tests. An alternative is to modify the tests to use more complex queries which are not eligible for the CQF fast path.

A preliminary list of tests which I found that are affected is:

• jstests/core/index/index_filter_commands_invalidate_plan_cache_entries.js
• jstests/core/query/plan_cache/plan_cache_clear.js
• jstests/core/query/plan_cache/plan_cache_sbe.js
• jstests/core/query/plan_cache/plan_cache_sbe_hinted.js
• jstests/core/sbe/from_plan_cache_flag.js
• jstests/core/sbe_plan_cache_autoparameterize_collscan.js
• jstests/noPassthrough/plan_cache_hits_and_misses_metrics.js
• jstests/noPassthrough/sbe_plan_cache_size_metric.js