Auto merge of #19530 - emilio:extend-not-much, r=jdm

style: Don't unconditionally extend() the declaration block vector.

Since it appears in profiles when used from CSSOM, like the one in the bug
mentioned in the comment.

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This commit is contained in:
bors-servo 2017-12-08 19:59:38 -06:00 committed by GitHub
commit f8a87a76b2

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@ -399,15 +399,28 @@ impl PropertyDeclarationBlock {
importance: Importance,
source: DeclarationSource,
) -> bool {
let all_shorthand_len = match drain.all_shorthand {
AllShorthand::NotSet => 0,
AllShorthand::CSSWideKeyword(_) |
AllShorthand::WithVariables(_) => ShorthandId::All.longhands().len()
};
let push_calls_count = drain.declarations.len() + all_shorthand_len;
match source {
DeclarationSource::Parsing => {
let all_shorthand_len = match drain.all_shorthand {
AllShorthand::NotSet => 0,
AllShorthand::CSSWideKeyword(_) |
AllShorthand::WithVariables(_) => ShorthandId::All.longhands().len()
};
let push_calls_count =
drain.declarations.len() + all_shorthand_len;
// With deduplication the actual length increase may be less than this.
self.declarations.reserve(push_calls_count);
// With deduplication the actual length increase may be less than this.
self.declarations.reserve(push_calls_count);
}
DeclarationSource::CssOm => {
// Don't bother reserving space, since it's usually the case
// that CSSOM just overrides properties and we don't need to use
// more memory. See bug 1424346 for an example where this
// matters.
//
// TODO: Would it be worth to call reserve() just if it's empty?
}
}
let mut changed = false;
for decl in &mut drain.declarations {