Implement constructor tearoffs support in IntelliJ

[eernstg]

This issue tracks support of the constructor tearoffs feature. See the enclosing meta-issue for details.

[devoncarew]

@eernstg - is the syntax finalized now (and ready for parsers to implement / syntax highlighters to be updated)?

cc @jwren

[eernstg]

I think it's a good idea to wait, in order to avoid duplicated work in case there are changes in the design before it is accepted. We will add a comment here (and on all the other issues associated with #46228) at that time.

[jwren]

@eernstg - Devon mentioned that the syntax is finalized enough to add to the Dart Plugin for IntelliJ. The feature link above is broken, is this link the correct source of truth? Thank you -- Jaime

[eernstg]

@jwren, thanks! Yes, the document was moved and the link you mentioned is the correct one today. Corrected it above, too.

[jwren]

Grammar changes required are here: https://dart-review.googlesource.com/c/sdk/+/197161

[jwren]

Initial PR to Alex out at JetBrains/intellij-plugins#819

[devoncarew]

@jwren - I believe the support landed?

[alexander-doroshko]

@devoncarew Only part of it. Things like const filledIntList = List<int>.filled; are not supported yet. Also tracked as https://youtrack.jetbrains.com/issue/WEB-52293.

[devoncarew]

Great, thanks for the update! FYI, depending on general readiness, we may or may not enable this in the beta release shipping the week of 9/13.

[devoncarew]

Also related: #47160

[devoncarew]

@jwren - can you confirm that this is generally on track for early October?

[jwren]

I have tried a few times to cover the last case (see above) without overhauling the BNF. @alexander-doroshko said he would try to take a look soon. To answer the question though, we'll figure it out in time for an early October release.

[alexander-doroshko]

Full syntax support is there in the latest published Dart plugin builds for all IDEs.

[devoncarew]

Great - thanks!