Give every Proxy invariant violation a descriptive TypeError message#2677
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22 invariant-check sites threw bare TypeErrors with no explanation of which trap misbehaved or why. Each now carries a V8-styled message naming the trap, the property and the violated invariant, matching the tone of the handful of sites that already had rich messages. The non-callable-trap error also drops the awkward "[handler] returned for property..." phrasing for V8's "'get' trap of proxy handler is not a function". Two merged conditions (getOwnPropertyDescriptor undefined-result and defineProperty missing-property) are split so each branch can name its own violation; evaluation order is unchanged. All messages interpolate only on the throw path. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01EsHuKuE4UihKZp5HYapDHE
lahma
enabled auto-merge (squash)
July 13, 2026 19:40
This was referenced Jul 15, 2026
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Final cleanliness piece of the Proxy series (#2674/#2675/#2676). 22 invariant-check sites threw bare TypeErrors with no hint of which trap misbehaved or why:
Every site now carries a V8-styled message naming the trap, the property, and the violated invariant — matching the tone of the handful of sites that already had rich messages (
get/set/deleteProperty). The non-callable-trap error also drops the awkward[object Object] returned for property 'get' of object ...phrasing for V8's'get' trap of proxy handler is not a function.Two merged conditions (getOwnPropertyDescriptor undefined-result, defineProperty missing-property) are split so each branch names its own violation — evaluation order unchanged. All messages interpolate only on the throw path, so hot paths are untouched (perf-flat by construction).
Verification: full Jint.Tests, PublicInterface, test262
~Proxy/~Reflectgreen (test262 never asserts messages); new exact-message assertions added to ProxyTests.🤖 Generated with Claude Code
https://claude.ai/code/session_01EsHuKuE4UihKZp5HYapDHE