Changes the applicability cache to evict only the least recently used idle snapshot when it reaches its 64-entry cap, instead of dropping every idle snapshot on each new key insertion.
Previously, lookups at the cap discarded the warm snapshot they were about to read, causing a full rescan of roots in active use. Now, recently used snapshots survive the cap, and a cached key is never dropped by its own lookup.
Adds a test reproducing the old failure and verifying the new eviction policy.
Adds release notes and a benchmark descriptor for the change.
Confidence Score: 5/5
The PR appears safe to merge; no actionable issues were found.
Summary
Changes the language-server applicability cache to remove the least recently used idle entry instead of clearing every idle entry at capacity.
Project applicability checks keep recently used cache entries and drop the oldest idle ones.
No actionable issues were found. Tests were inspected but not run.
Diagram
%%{init: {'theme': 'neutral'}}%%
flowchart TD
A[Look up root and configuration] --> B{Key already cached?}
B -->|Yes| E[Record latest use]
B -->|No| C{At capacity?}
C -->|Yes| D[Remove oldest idle entries if available]
C -->|No| F[Insert entry]
D --> F
F --> E
E --> G[Reuse valid result or share a scan]
