1540021 - Implement the String.prototype.replaceAll proposal

Status: RESOLVED FIXED

(Core :: JavaScript: Standard Library, enhancement, P3)

Description

[Alexandre Folle de Menezes]

The proposal is now on Stage 2.

Comment 1

[Mathias Bynens]

The proposal advanced to stage 3 at today’s TC39 meeting.

Comment 2

[André Bargull [:anba]]

Attachment: Bug 1540021: Implement String.prototype.replaceAll proposal. r=jorendorff!

This change doesn't include the String.prototype.matchAll modifications, because
those are already part of the main spec.

MCallOptimize.cpp:

• The inlining is more conservative than inlineIsRegExpObject, because it's not
  clear at this point we need the extra features from inlineIsRegExpObject.

String.js:

• The self-hosted part is slightly different than the current spec text, because
  it combines the match and replace loops. The non-functional replace part is
  implemented in C++, so we can reuse the existing C++ matcher functions.

String.cpp:

• Added some extra assertions to AppendDollarReplacement and also had to change
  the infallibleAppend call into a normal append call, because when called
  from replaceAll, we may not have reserved enough space in the StringBuffer.
• replaceAll has a specialised implementation when the pattern is the empty
  string, because in that case the pattern is interleaved in-between each
  character, so we don't need to find the next match and can also directly reserve
  the correct string length (when no '$' characters are present in the replacement
  string). This should allow users to update from the previous
  str.split("").join(r) pattern to str.replaceAll("", r) without loss of
  performance.
• When the pattern isn't the empty string, we reuse the existing StringMatch
  and AppendDollarReplacement functions to match and replace the pattern.

This feature is still restricted to Nightly, because no test262 tests are
currently available.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/705533ca2ccb
Implement String.prototype.replaceAll proposal. r=jorendorff

Comment 4

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/705533ca2ccb

Comment 5

[Mike Conca [:mconca]]

Thanks for submitting this, André. We really appreciate it.

Comment 6

[jakub.g]

For info this has was shipped in Safari 13.1 [1].
Are there any blockers that prevent unflagging it in Firefox? (apart from MDN docs?)

[1] https://webkit.org/blog/10247/new-webkit-features-in-safari-13-1/#javascript-improvements

Comment 7

[André Bargull [:anba]]

This ships in Firefox 77 (bug 1608168).

Comment 8

[Florian Scholz (Open Web Docs)]

Docs:
https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/77#JavaScript
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replaceAll