broken support for mark filter sets in OpenType lookups

RESOLVED FIXED in Firefox 47

Status

()

defect
RESOLVED FIXED
3 years ago
3 years ago

People

(Reporter: jfkthame, Assigned: jfkthame)

Tracking

({regression})

47 Branch
mozilla48
Points:
---
Dependency tree / graph

Firefox Tracking Flags

(firefox46 unaffected, firefox47 fixed, firefox48 fixed)

Details

Attachments

(1 attachment)

Assignee

Description

3 years ago
See discussion beginning at https://lists.freedesktop.org/archives/harfbuzz/2016-April/005533.html.

This was broken in harfbuzz 1.2.2, which we took in bug 1249861, and can disrupt the rendering of fonts with complex mark handling -- e.g. some Arabic-script fonts.

The fix is trivial, so we should cherry-pick it and uplift to FF47 so as to avoid shipping a release with the bug present.
Assignee

Updated

3 years ago
Keywords: regression
Assignee

Comment 1

3 years ago
We'll take a new harfbuzz version in bug 1251203 shortly, but as this is a regression with a trivial fix, I think we should cherry-pick it and uplift to FF47 rather than waiting for the new version to ride the train.
Attachment #8738943 - Flags: review?(jmuizelaar)
Assignee

Updated

3 years ago
Assignee: nobody → jfkthame
Status: NEW → ASSIGNED
Assignee

Comment 2

3 years ago
I tested (manually) that we currently have bad rendering of the Hussaini Nastaleeq font in Nightly, and this patch fixes it. I don't think we can readily add a reftest here (not without considerable effort to create a custom font, etc), but upstream now has a unit test so it shouldn't get regressed again.
Attachment #8738943 - Flags: review?(jmuizelaar) → review+
Assignee

Comment 3

3 years ago
https://hg.mozilla.org/integration/mozilla-inbound/rev/556ead25fa217327f8d116b4390db1f459704636
Bug 1262774 - Cherry-pick upstream fix for broken mark filter set support in harfbuzz. r=jrmuizel
Assignee

Comment 4

3 years ago
Comment on attachment 8738943 [details] [diff] [review]
Cherry-pick upstream fix for broken mark filter set support in harfbuzz

Approval Request Comment
[Feature/regressing bug #]: 1249861 (upstream regression, now fixed)

[User impact if declined]: some complex OpenType fonts will render incorrectly (some mark-handling lookups will fail)

[Describe test coverage new/current, TreeHerder]: upstream now has unit test covering this; patch tested manually with an affected Arabic font

[Risks and why]: minimal: trivial one-line fix for an obvious mistake

[String/UUID change made/needed]: none
Attachment #8738943 - Flags: approval-mozilla-aurora?

Comment 5

3 years ago
bugherder
https://hg.mozilla.org/mozilla-central/rev/556ead25fa21
Status: ASSIGNED → RESOLVED
Last Resolved: 3 years ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla48
Comment on attachment 8738943 [details] [diff] [review]
Cherry-pick upstream fix for broken mark filter set support in harfbuzz

Low risk, was manually tested, Aurora47+
Attachment #8738943 - Flags: approval-mozilla-aurora? → approval-mozilla-aurora+
Version: unspecified → 47 Branch
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