1544874 - ::marker with non-normal content not displayed if ::before or ::after is a list item

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Oriol Brufau [:Oriol]]

Attachment: marker-content.htm

.before > li::before {
  content: 'before';
  display: list-item;
  list-style-position: inside;
}
.content > li::marker {
  content: '1)';
}

<ol class="content"><li></li></ol>
<ol class="before"><li></li></ol>
<ol class="before content"><li></li></ol>

When ::marker wasn't implemented, this was displayed as

1.
1. 2. before
1. 2. before

Now it's displayed as

1)
1. 2. before
   2. before

In the 3rd case, the marker of the element is not displayed! It should be

1)
1. 2. before
1) 2. before

This seems to happen when the ::marker has a non-normal content, and the element has a ::before or ::after pseudo-element which is a list item.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

The content is there, it's just mispositioned. Mats, thoughts?

Comment 2

[Mats Palmgren (inactive)]

Attachment: Testcase #2

The bug occurs when we have a block child in the list item.

In that case, we position the marker box here:
https://searchfox.org/mozilla-central/rev/1b2636e8517aa48422ed516affe4d28cb7fa220a/layout/generic/nsBlockFrame.cpp#1287
with reflowOutput.BlockStartAscent() == 1073741823 (ASK_FOR_BASELINE)
because we never assigned it.
In the legacy code path we explicitly set it here:
https://searchfox.org/mozilla-central/rev/1b2636e8517aa48422ed516affe4d28cb7fa220a/layout/generic/nsBulletFrame.cpp#966
(so it's 15px once we get there, and so is position.mBaseline, so we set BStart = 0 there)

Comment 3

[Mats Palmgren (inactive)]

Attachment: Bug 1544874 - Add missing baseline alignment for non-legacy ::marker boxes when aligning to a "block line". r=emilio

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/d37377e818b4
Add missing baseline alignment for non-legacy ::marker boxes when aligning to a "block line".  r=emilio

Comment 5

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/d37377e818b4

Comment 6

[Web Platform Test Sync Bot (Matrix: #interop:mozilla.org)]

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/16499 for changes under testing/web-platform/tests

Comment 7

[Web Platform Test Sync Bot (Matrix: #interop:mozilla.org)]

Upstream PR merged