perf: use getpwnam() for tilde expansion, deduplicate hash lookup#380
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perf: use getpwnam() for tilde expansion, deduplicate hash lookup#380Koan-Bot wants to merge 1 commit intocpan-authors:mainfrom
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Two targeted optimizations in hot path functions:
1. _abs_path_to_file tilde expansion: replace getpwent() iteration loop
with direct getpwnam() call. The old code reset the passwd iterator
and scanned all entries sequentially to find one username — O(n) in
the number of system users. getpwnam() does the same lookup via NSS
in O(1).
2. _maybe_autovivify: cache the hash lookup result instead of accessing
%files_being_mocked{$abs_path} twice (once for the truthiness check,
once for the return value).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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What
Two targeted optimizations in frequently-called path resolution functions.
Why
Tilde expansion (
_abs_path_to_file): Thegetpwent()loop iteratedthrough ALL system password entries sequentially to find one username.
On systems with LDAP/AD backends, this can be extremely slow.
getpwnam()does the same lookup via NSS in O(1).
Autovivify check (
_maybe_autovivify):%files_being_mocked{$path}was accessed twice — once for the boolean check, once for the return value.
Single lookup with
if (my $existing = ...)eliminates the redundant access.How
endpwent/getpwentloop with singlegetpwnam()call_maybe_autovivifyTesting
No behavioral change — pure optimization. Existing tests cover both code paths.
🤖 Generated with Claude Code