1481866 - swap values of 2-value 'overflow' syntax so block is first and inline is second

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, enhancement)

Description

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

The CSS WG just resolved on https://github.com/w3c/csswg-drafts/issues/2988 to change the meaning of the 2-value overflow syntax.  We're the only engine that implements; we should switch to match this resolution (assuming we did it right in the first place, at least).

Comment 1

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

Attachment: Bug 1481866: Swap order of values in 'overflow' shorthand property. r=emilio

Comment 2

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

https://treeherder.mozilla.org/#/jobs?repo=try&revision=655f14c35b16b01f1cd9eafac059e3d0acac9647&group_state=expanded

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Comment on attachment 8999043 [details]
Bug 1481866:  Swap order of values in 'overflow' shorthand property.  r=emilio

Emilio Cobos Álvarez (:emilio) has approved the revision.

Comment 4

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

https://treeherder.mozilla.org/#/jobs?repo=try&revision=d4f19314cdfbfc2d1b34f9052bb3b0c38ec36475&group_state=expanded

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a377edbfae93
Swap order of values in 'overflow' shorthand property.  r=emilio

Comment 6

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

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/12393 for changes under testing/web-platform/tests

Comment 7

[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 8

[Eliza Balazs [:ebalazs_]]

https://hg.mozilla.org/mozilla-central/rev/a377edbfae93

Comment 9

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

Upstream PR merged

Comment 10

[Florian Rivoal]

This isn't quite right. The CSSWG's resolution is not to change from x/y to y/x, but from x/y to block/inline. In other words, not only swap the order, but also tie to logical rather than physical directions.

Comment 11

[Emilio Cobos Álvarez (:emilio)]

(In reply to Florian Rivoal from comment #10)
> This isn't quite right. The CSSWG's resolution is not to change from x/y to
> y/x, but from x/y to block/inline. In other words, not only swap the order,
> but also tie to logical rather than physical directions.

That is a very different (and breaking) change... So, for example, you'd make code that sets overflow, then reads out overflow-x / overflow-y not work anymore:

  document.body.style.overflow = "hidden";
  document.body.style.overflowX // ""

David, what should we do about this?

Comment 12

[Kohei Yoshino]

Posted the site compatibility note: https://www.fxsitecompat.com/en-CA/docs/2018/overflow-shorthand-syntax-has-been-updated-to-swap-2-values/

Comment 13

[Rachel Andrew]

I have updated the documentation for this change at https://developer.mozilla.org/en-US/docs/Web/CSS/overflow

A review of that would be appreciated.

Comment 14

[Emilio Cobos Álvarez (:emilio)]

I think we should back this out, given blink is going to ship x, then y, and we don't really have the infrastructure to implement the behavior that the WG really proposes, which involves implementing two new overflow logical properties, and making shorthands expand to different longhands depending of the syntax of the shorthand.

Comment 15

[Kohei Yoshino]

Okay, I’ve updated the site compatibility note to mark it reverted.

Comment 16

[Chris Mills [:cmills]]

Reverted in docs as well.