Bug 94688 – Layout test fast/js/toString-overrides.html should expect TypeError when toLocaleString is overwritten

• Status: NEW
• Component: Tools / Tests

[Ulan Degenbaev]

Layout test fast/js/toString-overrides.html has the following test cases:

> Number.prototype.toLocaleString = "invalid";
> shouldBe("[1].toLocaleString()", "'1'");
> RegExp.prototype.toLocaleString = "invalid";
> shouldBe("[/r/].toLocaleString()", "'toString2'");

According to ECMA 262/15.4.4.3, both calls to "toLocaleString()" should throw TypeError because steps 8.a, 8.b of the spec algorithm state:

> 8.a Let func be the result of calling the [[Get]] internal method of elementObj with argument "toLocaleString".
> 8.b If IsCallable(func) is false, throw a TypeError exception.

String "invalid" is not callable.

Both Chrome and Firefox throw TypeError in these cases:

> FAIL [1].toLocaleString() should be 1. Threw exception TypeError: Property 'toLocaleString' of object toString is not a function
> FAIL [/r/].toLocaleString() should be toString2. Threw exception TypeError: Property 'toLocaleString' of object toString2 is not a function