1378190 - stylo: Some spring cleanup in ServoRestyleManager.

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, enhancement)

Description

[Emilio Cobos Álvarez (:emilio)]

Just something that I think makes the code easier to follow. Also, adding a few docs here and there.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1378190: Try to make ServoRestyleManager easier to follow.

Review commit: https://reviewboard.mozilla.org/r/154244/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/154244/

Comment 2

[Cameron McCormack (:heycam)]

Comment on attachment 8883359 [details]
Bug 1378190: Try to make ServoRestyleManager easier to follow.

https://reviewboard.mozilla.org/r/154244/#review159380

Thanks, looks good.  As my old chef housemate used to say, "clean as you go". :-)

::: layout/base/ServoRestyleManager.cpp:997
(Diff revision 1)
> +  // We assume that id and class attributes are referenced from selectors, and
> +  // thus record them.

Nit: Maybe "IDs and classes are used in selectors" rather than "id and class attributes are referenced from selectors", since the latter sounds a bit like it's talking about attribute selectors.

::: layout/base/ServoRestyleManager.cpp:1000
(Diff revision 1)
> +  // TODO(emilio): We keep a filter of the ids in use somewhere in the StyleSet,
> +  // presumably we could try to filter the old and new id.

Yeah, we could do this.  Although I think modifying id="" attributes on existing elements is not super common.

::: layout/base/ServoRestyleManager.cpp:1083
(Diff revision 1)
>    if (aAttribute == nsGkAtoms::style) {
> -    PostRestyleEvent(aElement, eRestyle_StyleAttribute, nsChangeHint(0));
> +    restyleHint |= eRestyle_StyleAttribute;
> +  } else if (AttributeChangeRequiresSubtreeRestyle(*aElement, aAttribute)) {
> +    restyleHint |= eRestyle_Subtree;

Nit: I think the structure with the "else if" here assumes that AttributeChangeRequiresSubtreeRestyle won't return true for style="".  That is the case, but it seems like we should avoid relying on that.  We could swap the order of these two things (since the eRestyle_Subtree will subsume the eRestyle_StyleAttribute work), but it is nice to check style="" first I suppose.  Not sure I have a good suggestion that makes the code look as neat as you have it here. :-)

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Comment on attachment 8883359 [details]
Bug 1378190: Try to make ServoRestyleManager easier to follow.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/154244/diff/1-2/

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Comment on attachment 8883359 [details]
Bug 1378190: Try to make ServoRestyleManager easier to follow.

https://reviewboard.mozilla.org/r/154244/#review159386

::: layout/base/ServoRestyleManager.cpp:997
(Diff revision 1)
> +  // We assume that id and class attributes are referenced from selectors, and
> +  // thus record them.

Agreed, updated the comment :)

::: layout/base/ServoRestyleManager.cpp:1083
(Diff revision 1)
>    if (aAttribute == nsGkAtoms::style) {
> -    PostRestyleEvent(aElement, eRestyle_StyleAttribute, nsChangeHint(0));
> +    restyleHint |= eRestyle_StyleAttribute;
> +  } else if (AttributeChangeRequiresSubtreeRestyle(*aElement, aAttribute)) {
> +    restyleHint |= eRestyle_Subtree;

Yeah, I also noticed this... But it seems unlikely that we'd start doing subtree restyles for style attribute changes, so I think it's ok.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/ac434d1aa45d
Try to make ServoRestyleManager easier to follow. r=heycam

Comment 6

[Phil Ringnalda (:philor)]

https://hg.mozilla.org/mozilla-central/rev/ac434d1aa45d