827698 - [css3-animations] determine the number of animations using the length of the 'animation-name' list

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, defect)

Description

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

We currently determine the number of CSS animations based on the longest animation-* property, rather than the length of the animation-name list, as we should.

I suspect this is a case where I concluded the spec was wrong, sent comments to www-style, and then implemented what it said instead of what it should say... and then by the time the spec got fixed, forgot that I'd done that.

Hopefully most users of animations are using the animation shorthand, and are therefore unlikely to run into compatibility issues; there is a risk of that, though.

Comment 1

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

http://dev.w3.org/csswg/css3-animations/#animation-name-property is the relevant bit of spec:

If the lists of values for the other animation properties do not have the same length, the length of the ‘animation-name’ list determines the number of items in each list examined when starting animations. The lists are matched up from the first value: excess values at the end are not used. If one of the other properties doesn't have enough comma-separated values to match the number of values of ‘animation-name’, the UA must calculate its used value by repeating the list of values until there are enough. This truncation or repetition does not affect the computed value.

Comment 2

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

Attachment: Use the length of the 'animation-name' list when determining how many animations to run.

Comment 3

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

https://tbpl.mozilla.org/?tree=Try&rev=e63a1700f149

Comment 4

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 699011 [details] [diff] [review]
Use the length of the 'animation-name' list when determining how many animations to run.

r=me

Comment 5

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

https://hg.mozilla.org/integration/mozilla-inbound/rev/fb69b7be1c0e

Comment 6

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/fb69b7be1c0e

Comment 7

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/fb69b7be1c0e

Comment 8

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/fb69b7be1c0e