Fix GC_test#test_enable leaving GC disabled for the rest of the suite - #3059
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`GC.enable` returns whether GC was *disabled* before the call (true when the call actually re-enabled GC), not whether it was enabled. The ensure clause `GC.disable unless was_enabled` therefore inverted the restore: in the common case where GC is enabled when the test starts, GC.enable returns false and the ensure clause disables GC permanently. Every test that runs after GC_test then executes with GC turned off, so the whole stdlib test process accumulates garbage until exit. On the ruby/ruby Windows CI runners this reaches the process memory limit and the suite dies with NoMemoryError (deterministically), and on all platforms it silently changes what later tests exercise. Rename the variable to what the value actually means and restore the previous state with `GC.disable if was_disabled`, mirroring test_disable. Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
soutaro
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`GC.stress = true` runs a full GC on every allocation, and each `assert_send_type` allocates heavily while parsing the method type and type checking the call trace. Since ruby#3059 stopped `test_enable` from leaking a disabled GC into the rest of the suite, stress mode is finally live during this test, and the five assertions between `GC.stress = 0` and `GC.stress = false` turn the whole stdlib suite from 193s into 827s -- 647s of it inside this one method. The cost scales with heap size, so it is far worse in the full suite than when the file runs alone. The assertions only check the types of the return values, so no GC needs to actually run. Disable GC for the duration and restore both the stress mode and the previous enabled state afterwards. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NtDw9t8cMiaqT2s8wwSsDt
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GC.enablereturns whether GC was disabled before the call (true when the call actually re-enabled GC), not whether it was enabled. The ensure clauseGC.disable unless was_enabledtherefore inverted the restore: in the common case where GC is enabled when the test starts, GC.enable returns false and the ensure clause disables GC permanently.Every test that runs after GC_test then executes with GC turned off, so the whole stdlib test process accumulates garbage until exit. On the ruby/ruby Windows CI runners this reaches the process memory limit and the suite dies with NoMemoryError (deterministically), and on all platforms it silently changes what later tests exercise.
Rename the variable to what the value actually means and restore the previous state with
GC.disable if was_disabled, mirroring test_disable.