1682006 - Don't call Truncate() on the return string in GetPropertyValue.

Status: RESOLVED FIXED

(Core :: DOM: CSS Object Model, defect, P2)

Description

[Emilio Cobos Álvarez (:emilio)]

Instead, assert it's empty.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1682006 - Don't call Truncate() on the return string in GetPropertyValue. r=#style

Turns out this causes a bit of overhead when appending to an AutoString,
because Truncate() calls SetToEmptyBuffer(), which makes it go from
inline-string to buffer string, and next time we append we need to turn
the string from a buffer-based string to an inline string again, which
is some minor, but measurable, work, while profiling some
micro-benchmarks.

Probably we should make Truncate() a no-op for a zero-length string, but
I'll send that separately.

Comment 2

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1682006 - Avoid silly propID -> string -> propID conversion in nsComputedDOMStyle. r=#style

Depends on D99493

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2809cb024474
Don't call Truncate() on the return string in GetPropertyValue. r=xidorn
https://hg.mozilla.org/integration/autoland/rev/ca95578df71a
Avoid silly propID -> string -> propID conversion in nsComputedDOMStyle. r=xidorn

Comment 4

[Bogdan Tara[:bogdan_tara | bogdant]]

https://hg.mozilla.org/mozilla-central/rev/2809cb024474
https://hg.mozilla.org/mozilla-central/rev/ca95578df71a