Resolve Proxy-backed JS file variable addresses#396
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This was referenced Jun 12, 2026
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Since the prototype pollution hardening in #165, the file variable source has gated every address segment on
Object.prototype.hasOwnProperty, which does not consult a Proxy'shasorgettraps. Variables that read virtual properties from Proxy-backed objects returned by JS files, such as${file(./vars.js):cfg.settings}wherecfgis a Proxy, therefore began resolving to null. This change restores those lookups by deferring to the proxy's own traps: when a value is a Proxy and does not claim the segment as an own property, the segment is now resolved through ordinary property access, which invokes thegettrap. Proxies can only originate from JS files, which are already executed as trusted code, so consulting their traps introduces no new attack surface, and the own-property check itself already invokes the proxy'sgetOwnPropertyDescriptortrap today. The behaviour for every non-Proxy value is unchanged, including the guarantees that inherited properties are not traversable and that own__proto__data properties parsed from JSON files still resolve. To keep the hardening posture uniform, the__proto__,prototypeandconstructorkeys remain blocked on proxies unless they are claimed as own properties. The variables guide now documents these semantics.Fixes #384.