fix: restrict Subs style to package-local subs only#193
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toddr merged 1 commit intocpan-authors:mainfrom Mar 22, 2026
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The Subs style used UNIVERSAL::can() to look up handlers, which walks
the inheritance tree. This means XML element names could dispatch to
inherited methods (e.g. a base class's connect() or cleanup()), even
though the documentation says "a sub by that name in the package
specified by the Pkg option".
Replace can() with direct symbol table lookup (defined &{"Pkg::tag"})
so only subs actually defined in the target package are called. This
matches the documented behavior and prevents unintended method dispatch
through UNIVERSAL or parent classes.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
toddr
approved these changes
Mar 22, 2026
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What
Restrict the Subs style to only dispatch to subs defined directly in the target package, not inherited methods.
Why
The Subs style used
UNIVERSAL::can()to find handlers, which walks the entire inheritance tree. This means XML element names like<connect/>or<cleanup/>could invoke inherited base class methods — a behavior inconsistent with the documentation ("a sub by that name in the package specified by the Pkg option") and potentially dangerous if the package inherits from a class with side-effectful methods.How
Replaced
$expat->{Pkg}->can($tag)with a direct symbol table check:defined &{"Pkg::$tag"}. This only finds subs actually defined in the package, matching the documented contract. Applied to both Start and End handlers.Testing
t/subs_inherited.twith 4 tests covering:isa,can,VERSION) are not triggeredtag_) also uses direct lookup🤖 Generated with Claude Code