1011369 - Implement line-break property of CSS3 Text

Status: RESOLVED FIXED

(Core :: Layout: Text and Fonts, enhancement, P3)

Description

[Makoto Kato [:m_kato]]

WebKit/Blink and Trindent are implemented, but it has no property in Gecko.

Comment 1

[Mats Palmgren (inactive)]

(Bugs about implementing new CSS properties are usually filed in "CSS
Parsing and Computation", so moving it there for consistency.)

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

(In reply to Mats Palmgren (:mats) from comment #1)
> (Bugs about implementing new CSS properties are usually filed in "CSS
> Parsing and Computation", so moving it there for consistency.)

Really?  I'd keep it in the component where the bulk of the code would live.  And the CSS side here is trivial.

Comment 3

[Mats Palmgren (inactive)]

My mistake then;  I thought it was the established practice for bugs that
adds new CSS properties.

Comment 4

[Makoto Kato [:m_kato]]

Although, I am migrating ICU into m-c (by some bugs for ECMA-402 support), ICU has this line-break rule now
http://www.icu-project.org/trac/changeset/37037

Comment 5

[Koji Ishii]

FYI, Blink is going to unprefix 'line-break' property (actually, we had, accidentally, now trying to be official.)

mkwst@ suggested we should update our status here, hope this info can be any help for you.

Intent to Ship: Unprefix CSS 'line-break' property
https://groups.google.com/a/chromium.org/d/msg/blink-dev/RHeWSxMIVK8/g5NJgZo9AQAJ

Comment 6

[Boris Zbarsky [:bzbarsky]]

It would be good to not have this random incompatibility.

Makoto-san, do you happen to have an idea of how much work this is to implement?

Comment 7

[Makoto Kato [:m_kato]]

(In reply to Boris Zbarsky [:bz] (vacation until 7/7) from comment #6)
> It would be good to not have this random incompatibility.
> 
> Makoto-san, do you happen to have an idea of how much work this is to
> implement?

If we can keep our current line breaker rule that isn't same as UAX#14, it isn't difficult.  If line-break property need additional rule again our rule.  If we require this on 57 or 58, I will start the implementation.

If we have to change it to UAX#14 based, it isn't easy.  One is file size (+3MB with ICU's rule), and others are compatibility  against old Gecko.  File size is critical for mobile team and we don't use ICU on Fennec's release channel yet.

Comment 8

[Boris Zbarsky [:bzbarsky]]

> If we require this on 57 or 58, I will start the implementation

I don't know that we have a target for this yet.  57 is probably not realistic no matter what, but "sometime in the nearish future" might be nice if everyone else is shipping this....

Comment 9

[Kan-Ru Chen [:kanru] (UTC+9)]

I wonder if it's possible to base this on the xi-unicode library that Servo is also using to implement line breaking. Looks like bug 1290022 is investigating the possibility.

Comment 10

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1011369 - Add parsing of the loose|normal|strict values of the CSS line-break property. r=emilio

Depends on D29817

Comment 11

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1011369 - Pass word-break and line-break properties to the line-breaker as two distinct enum class parameters. r=m_kato

Depends on D30785

Comment 12

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1011369 - Implement loose|normal|strict line-break values by remapping the linebreak class of affected characters. r=m_kato

Depends on D30786

Comment 13

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1011369 - Restrict some line-break behaviors to Chinese and Japanese contexts, as per spec. r=m_kato

Depends on D30787

Comment 14

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1011369 - Update metadata for WPT tests that now pass. r=m_kato

Depends on D30788

Comment 15

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1011369 - Reduce the available width slightly in line-break-loose-017a because a couple of the target characters may be less then .2em wide. r=m_kato

Depends on D30788

Comment 16

[Jonathan Kew [:jfkthame]]

Just FTR, I plan to land this (along with bug 1531715) after the mozilla-68 soft freeze is over.

Comment 17

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e7b525e15531
Add parsing of the loose|normal|strict values of the CSS line-break property. r=emilio
https://hg.mozilla.org/integration/autoland/rev/f339909acbc3
Pass word-break and line-break properties to the line-breaker as two distinct enum class parameters. r=m_kato
https://hg.mozilla.org/integration/autoland/rev/436e3199c386
Implement loose|normal|strict line-break values by remapping the linebreak class of affected characters. r=m_kato
https://hg.mozilla.org/integration/autoland/rev/2607e7773ed5
Restrict some line-break behaviors to Chinese and Japanese contexts, as per spec. r=m_kato
https://hg.mozilla.org/integration/autoland/rev/b695489a68c4
Reduce the available width slightly in line-break-loose-017a because a couple of the target characters may be less then .2em wide. r=m_kato
https://hg.mozilla.org/integration/autoland/rev/43952b7f9de8
Update metadata for WPT tests that now pass. r=m_kato

Comment 18

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

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/16924 for changes under testing/web-platform/tests

Comment 19

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

Upstream web-platform-tests status checks passed, PR will merge once commit reaches central.

Comment 20

[Daniel Varga [:dvarga]]

https://hg.mozilla.org/mozilla-central/rev/e7b525e15531
https://hg.mozilla.org/mozilla-central/rev/f339909acbc3
https://hg.mozilla.org/mozilla-central/rev/436e3199c386
https://hg.mozilla.org/mozilla-central/rev/2607e7773ed5
https://hg.mozilla.org/mozilla-central/rev/b695489a68c4
https://hg.mozilla.org/mozilla-central/rev/43952b7f9de8

Comment 21

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

Upstream PR merged

Comment 22

[Florian Rivoal]

WPT lacked a number of tests for this feature. The coverage has now been completed, and firefox fails some of them.

New tests introduced by: https://github.com/web-platform-tests/wpt/pull/18000

Comment 23

[Boris Zbarsky [:bzbarsky]]

I filed bug 1568219 to track those failures.