ruby-grape / grape / 22399578588

97%

master: 97%

Pull #2660

github

Fix thread safety: move mutable ParamsScope state into per-request ParamScopeTracker

ParamsScope instances are shared across requests (definition-time objects).
The mutable `@index` and `@params_meeting_dependency` ivars were being
written during request processing, creating a race condition under concurrent
requests.

Introduces `ParamScopeTracker` which stores all per-request mutable state
(array indices + qualifying params) in a `Fiber[FIBER_KEY]` entry, isolating
each request's state from others. `Endpoint#run_validators` sets up the
tracker via `ParamScopeTracker.track {}`. `AttributesIterator#store_indices`
writes to it; `ParamsScope#full_name` and `#qualifying_params` read from it.

Uses `Fiber[]` (not `Thread.current[]`) so fiber-based servers (e.g. Falcon)
correctly isolate per-request state within each fiber.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1076 of 1162 branches covered (92.6%)

Branch coverage included in aggregate %.

62 of 62 new or added lines in 5 files covered. (100.0%)

3326 of 3382 relevant lines covered (98.34%)

44594.8 hits per line