contain-size-multicol-003.html still expects "contain:size" to suppress baseline alignment, in its very first div. That's now an incorrect expectation, as of bug 1491235. Apparently the tests still "passes" for now (maybe because multicol elements do their own baseline-suppression by accident?), but it stops passing as of bug 1491915. We need to split the baseline-related chunk of this test out into a separate test that uses 'contain:layout' rather than 'contain:size'.

Here's the chunk of the test that needs splitting out: https://searchfox.org/mozilla-central/rev/c0b26c40769a1e5607a1ae8be37fe64df64fc55e/layout/reftests/w3c-css/submitted/contain/contain-size-multicol-003.html#40-44

A quick search of "baseline alignment as if" shows the following chuck in contain-size-button-001.html. It might need to be updated, too, but I'm not sure. https://searchfox.org/mozilla-central/rev/647b9eb1099e373e079e16f147f74f3d1d65eed3/layout/reftests/w3c-css/submitted/contain/contain-size-button-001.html#74-76 Also, there's a typo "basic" in <fieldset class="basc">. After fixing that, maybe we don't need the "fieldset" style. https://searchfox.org/mozilla-central/rev/647b9eb1099e373e079e16f147f74f3d1d65eed3/layout/reftests/w3c-css/submitted/contain/contain-size-fieldset-002-ref.html#40

I filed bug 1508441 on the button issue from comment 2 - looks like our impl is broken (out of date) there.

Note that Firefox doesn't actually match this expectation yet, so I've added a 'fails' annotation to the manifest with the followup bug number. Also, this patch makes several other improvements to this test: - remove red background in testcase. This was making the testcase spuriously fail in Chrome, because Chrome paints (at least) a 1px-tall background-area on empty buttons, which meant a 1px-tall red area in the testcase vs. a 1px-tall gray area in the reference case. - clear floats to prevent them from piling up awkwardly. - use 'vertical-align:top' to turn off baseline alignment in parts of the test where the testcase has text and the reference case does not (and where we're not intentionally testing the baseline's influence on layout). Depends on D12614

Depends on D12615

Note that we don't get this correct for form controls yet, so the -002 test is annotated as "fails" for now. Depends on D12616

This class wasn't applied due to a typo, and it's unnecessary anyway -- there's a separate 'fieldset {...}' CSS rule further down in the file that has the same effect (hiding the border and the textual contents). Depends on D12617

TYLin, I'm hoping you're up for reviewing here. :) (No big rush, sorry to post just before the holiday weekend -- this can definitely wait until next week.) I'm not sure how much you've looked at containment, but it's not too complicated -- the main backstory here is that 'baseline' suppression was moved from 'contain:size' to 'contain:layout' (which we mostly implemented in bug 1491235), and we still have some work to do on updating tests (this bug!) and implementation (bug 1508441) to stay kept up with that spec-change. Try run: https://treeherder.mozilla.org/#/jobs?repo=try&revision=b1ea4a6a5c634f92d5195b035731a674baa2e0dc

Pushed by dholbert@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/2ca8fb2abe07 part 1: Uncomment/invert expectations in some reftests to now expect that contain:size *does not* interfere with baseline alignment. r=TYLin https://hg.mozilla.org/integration/autoland/rev/1fe8baada237 part 2: Adjust reftest 'contain-size-button-001.html' to expect that contain:size *does not* suppress baseline alignment. r=TYLin https://hg.mozilla.org/integration/autoland/rev/c20d49e40432 part 3: Update titles to remove stale references to baseline alignment, in two reftests that don't test baseline alignment. r=TYLin https://hg.mozilla.org/integration/autoland/rev/c99b6f6c3bcf part 4: Add dedicated reftests to verify that "contain:layout" suppresses baseline alignment. r=TYLin https://hg.mozilla.org/integration/autoland/rev/a3755a4ba5aa part 5: Remove stray/unused markup for "basic"/"basc" class in contain-size-fieldset-002-ref.html. r=TYLin

https://hg.mozilla.org/mozilla-central/rev/2ca8fb2abe07 https://hg.mozilla.org/mozilla-central/rev/1fe8baada237 https://hg.mozilla.org/mozilla-central/rev/c20d49e40432 https://hg.mozilla.org/mozilla-central/rev/c99b6f6c3bcf https://hg.mozilla.org/mozilla-central/rev/a3755a4ba5aa

WPT import at https://github.com/web-platform-tests/wpt/pull/14264

The test was pointing to the wrong reference. Dunno if it's fine to upload a patch here or if I should report a different bug.

(In reply to Manuel Rego Casasnovas from comment #13) > Created attachment 9029358 [details] [diff] [review] > 0001-Bug-1507663-Fix-reference-in-contain-layout-suppress.patch > > The test was pointing to the wrong reference. > > Dunno if it's fine to upload a patch here or if I should report a different > bug. I think usually we don't reopen bugs or land patches in FIXED bugs, so I'd file a new one blocking this one :)