972119 - Simplify logic in nsCSSFrameConstructor::ConstructDocElementFrame

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Daniel Holbert [:dholbert]]

While working on bug 969460, I noticed an opportunity to simplify some logic in nsCSSFrameConstructor::ConstructDocElementFrame.

Filing this bug on doing that.

Comment 1

[Daniel Holbert [:dholbert]]

Attachment: fix v1

Here's the patch.

Much-easier-to-read "diff -w" version coming up.

Comment 2

[Daniel Holbert [:dholbert]]

Attachment: fix v1 [diff -w version]

(This is the version you probably want to review.)

So the idea here is to:
 (a) Invert the "Tag() == svg" logic, so that an early-return gets moved from "else"-body to "if"-body, which does away with the need for the "else" entirely.

 (b) Drop the unnecessary 'docElemIsTable' variable

 (c) Flatten "else { if" into "else if" to save on indentation.

Comment 3

[Daniel Holbert [:dholbert]]

and the point of all this is that now this function ends up looking like:

 if (style/tag is $FOO) {
   set up a particular frame;
 } else if (style/tag is $BAR) {
   set up a particular frame;
 } else if (style/tag is $BAZ) {
   [...etc...]
 } else {
   set up a block;
 }

Comment 4

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 8375227 [details] [diff] [review]
fix v1

r=me.  Thank you for the diff -w!

Comment 5

[Daniel Holbert [:dholbert]]

Thanks for the review!

Try run: https://tbpl.mozilla.org/?tree=Try&rev=bebe01ea1dd6

Comment 6

[Daniel Holbert [:dholbert]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/72a491f40e45

Comment 7

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/72a491f40e45