ruby-grape / grape / 24635096923

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master: 97%

Pull #2687

github

Skip backtrace capture on internal validation exceptions

Grape::Exceptions::Validation is raised once per bad attribute on every
failing request; Grape::Exceptions::ValidationArrayErrors wraps them and
is raised once per validator. Both are caught internally by
Endpoint#run_validators and their backtraces are never surfaced — they
point into Grape's own validator stack, not user code, and have no
diagnostic value.

Ruby's +raise+ only captures a backtrace if the exception's backtrace
ivar is nil. Pre-seeding it via +set_backtrace(EMPTY_BACKTRACE)+ in
+initialize+ makes +raise+ skip the C-level +make_backtrace+ call
entirely. At representative prod stack depth (80-150 frames) this saves
~1-2 µs per raise.

The outer Grape::Exceptions::ValidationErrors is untouched — its
backtrace is preserved for anyone doing +rescue_from ValidationErrors+
or shipping validation failures to error-reporting tools.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

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