lib: assert.throws('string', TypeError, 'whatever') passes when it shouldn't

[bnoordhuis]

assert.throws('string', TypeError, 'whatever');  // should fail but doesn't

From here:

assert.throws() calls the first argument as a function. The result is a TypeError when the input is a string but it doesn't seem to check that the exception message matches.

[cjihrig]

The third argument isn't supposed to be validated is it? The documentation doesn't seem to imply that it should. To validate the exception message, the second argument should be a regex or function.

The third argument should be included in the error message though, right? That doesn't seem to be happening.

[dougwilson]

The third argument is the message to put in the AssertionError, like like all the other stuff in assert (the last argument is the assertion message).

[dougwilson]

Checking the thrown exception message would be to give a string as the second argument, rather than a constructor (you can also provide a RegExp object as the second argument).

[cjihrig]

Expects block to throw an error. error can be constructor, RegExp or validation function.

I don't think strings are supported as the second arguments.

Is there a specific reason that the assert module doesn't do a better job at input validation? For example, instead of blindly treating the first argument to throws() as a function, maybe it should validate that it is actually a function.

[bnoordhuis]

Alright, seems I was wrong about the third argument. Let me rephrase: assert.throws('string', TypeError) passes for the wrong reasons. I think it should either throw a TypeError ("first argument must be a function") or eval() the argument, like the assert functions in the SM and V8 test suites.

[cjihrig]

@bnoordhuis +1 on throwing on bad input. I'll work on this.

[caitp]

what if the assert library were just changed to eval() if the first argument is a string? mjsunit does it like this, it's convenient :> (as suggested above, I guess)

[cjihrig]

Closed in 14dc917

[caitp]

Think I like the v8 behavior better there