Some assertions generate always changing messages when failing

[youennf]

When failing, some assertions dump token values which always change test run after test run.
This defeats WebKit test infrastructure which is checking text output against expected text output.

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[jgraham]

Constant assertion text is explicitly not part of the contract that th.js users are supposed to conform to (indeed the harness itself fills variables into the failure message). What must be constant is the title of each test.

It seems like this is a bug in the WebKit integration.

[hallvors]

I can see some value in how WebKit's framework is operating - it certainly simplifies regression testing to have an "expected" output for all tests - and it's not a big issue to take in these few changes, so I just merged them. However there's probably going to be a lot more of this and @jgraham is right - testharness.js aims to be human user friendly and show at a glance the expected and the given value, so it might be better to have an intermediate step before you save the results in your framework, processing the results.

[youennf]

@jgraham, I do not disagree (on the contrary) that WebKit infrastructure could be made more aligned with WPT infrastructure. But consensus on that is not reached within WebKit community and progress is made slow.
In the meantime, minor modifications like these ones are helpful.
Thanks for merging it!

[jgraham]

I don't object to this being merged, but I will certainly object if you go through the whole of wpt and try to make the same changes.

My suggestion is that you either collect results in an entirely different way for testharness.js tests compared to other layout tests or implement a testharnessreport.js that produces output only from the tests and not the individual asserts.

If you want me to explain the testharness situation to the rest of the WebKit community please CC me on any relevant mailing list threads.