tree 0ed4a1dffb93ffce88946082595a200a85d8c201
parent efb3f85c7e9c1537e275765d11ad8de9f5282da5
author Stevie Strickland <sstrickl@google.com> 1552992015 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1552992015 +0000

[VM] Partial support for named regexp captures.

See https://github.com/tc39/proposal-regexp-named-groups
for a high-level description of the feature and examples.  This is one of the
features requested in https://github.com/dart-lang/sdk/issues/34935.

This is a partial implementation because while there is a way to retrieve
groups via Dart by name, it requires casting the returned Match to the
new RegExpMatch interface to avoid changing the RegExp interface.
Changing the RegExp interface will happen in a future update, since there
are other planned changes to the RegExp interface coming soon and that way
we only change it once. See https://github.com/dart-lang/sdk/issues/36171
for more details on the planned changes.

Also, since only BMP regular expressions are supported, not full
Unicode ones (i.e., those with the /u flag in ECMAscript), \k<NAME>
will only be parsed as a named back reference if there are named
captures in the string. Otherwise, the \k will be parsed as the identity
escape for backwards compatibility. The new tests illustrate this
difference.

Change-Id: Ieeb0374813db78924c9aa8ac3e652dfb6d4a5934
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/95461
Commit-Queue: Stevie Strickland <sstrickl@google.com>
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Jenny Messerly <jmesserly@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>