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Incorrect results for [[Get]] and [[HasProperty]] with Typed Array in prototype

See original GitHub issue

There was previously an inconsistency between [[Get]]/[[Set]] and [[HasProperty]] as noted in https://github.com/tc39/ecma262/issues/347. However, we did not comply with the old semantics either (our [[HasProperty]] seemed to be guarded on the receiver as well). The new semantics remove all the receiver checks.

var o = {__proto__: new Int32Array(100)};
Object.prototype[1.3] = 100;
print(o[1.3]);
print(Reflect.has(o, '1.3'));

Expected: undefined/false (same as v8) Actual: 100/true (same as sm)

Issue Analytics

State:
Created 8 years ago
Comments:13 (13 by maintainers)

Top GitHub Comments

1reaction

dilijevcommented, Jun 13, 2016

@bterlson @ianwjhalliday - ignore previous comment. A closer look showed that we were mistaken (cc @curtisman @Yongqu).

Fix in progress.

0reactions

bterlsoncommented, Jul 21, 2016

The original bug’s expected behavior is indeed what is expected.

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