Library augmentations

[jakemac53]

Tracking issue, see feature spec here https://github.com/dart-lang/language/blob/main/working/augmentation-libraries/feature-specification.md

[Lootwig]

While this is under development, is there any way to tell which version of the spec corresponds to a particular version of the dart SDK? (in particular, a quick way to figure out that sdk 3.7.0-106.0.dev was created when augment super() and import augment 'other.dart' existed)

EDIT: note, my analyzer crashes when encountering an augment super expression with an UnimplementedError: AstBuilder.handleAugmentSuperExpression, and syntax highlighting works perfectly fine for the currently specified version, but I get a runtime error when trying to use augmented if I don't use the outdated syntax - is something in my installation broken?

[jakemac53]

This feature is under active development, the implementations won't perfectly match the spec at any given state and also won't even match each other (there are two implementations at least, the CFE and analyzer).

In particular both of those teams are undergoing some large refactors to support enhanced parts at the moment, and then they will start actively implementing augmentations further. But, it will be quite some time before they are generally usable and stable.