Feedback on "closing labels" preview feature

v2.3.1 includes a preview feature enabled with the dart.previewFlutterCloseTagDecorations: true setting. This adds “closing tag” decorations to the closing parens of constructor calls within build methods.

This feature is behind a flag because it’s incomplete, has sub-optimal performance and may not work reliably. It is being shipped solely for feedback on the idea and may require analyzer work in order to support in a reliable way.

Please post your feedback below!

Known issues:

These are things that (probably) can’t be addressed without support from the analyzer.

• [Perf] Doesn’t scale well due to reliance on Outlines, Highlights and repeated getHover calls
• Currently identifies build methods based on return type string (Widget)
• Only shows constructors, doesn’t show end of lists (children, actions)

Suggestions:

These are things that can be improved in the preview.

• Support const as well as new
• Prefix with // instead of / so looks a bit like a comment marking the end
• Improve styling
• Fix flicker when typing quickly (or holding keys) caused by not being able relate analyzer notifications with document versions - just keep resetting a timeout and only update after there’s been no update for x milliseconds (where x > expected latency for the update)
• Show decorations in any Widget-returning method
• Don’t show annotations against characters other than ) to mitigate out-of-sync notifications
• Allow color to be customised rather than reusing an existing style

[DanTup]

I’ve shipped Dart Code v2.4.0. This includes an implementation of “closing tags” that uses the analysis server (you must be using at least 1.25.0-dev.11.0 which was released yesterday; flutter is also using it if you update).

It’s still behind a flag (though there’s a new flag name dart.previewClosingLabels since it’s not flutter-specific - though the old flag still works) to get some more feedback (it now appears for all Dart!).

Please try it out 😃

[DanTup]

@dvdwasibi

it would be nice to specify the style (color) of the closing tags.

I’ve added this (#408) for the “real” version (coming soon) though I’m hoping to get confirmation from MS that the way I did it is wonky and there’s a better way =)

It’ll be done by setting a theme colour named dart.closingLabels. It’ll default to the colour of tab.inactiveForeground which is the one shown in my last screenshot above (and should have a similarly reasonable default for light themes).

Colours are customised by adding workbench.colorCustomizations to your settings (or using a theme which has it; which is none!):

"workbench.colorCustomizations": {
    "dart.closingLabels": "#ff0000"
}