Files
sdk/pkg/analysis_server
Konstantin Shcheglov 5ed538a532 Bug fix: implement missing diagnostic implementsSuperClassConstraint.
It is disabled when augmentations feature is enabled.

This is not a breaking change, because CFE did report this error.

The relevant reason is indirect, not a single sentence saying “on A
implements A is forbidden”.

Spec chain:

1. In dartLangSpec.tex:6019, a mixin declaration is modeled as:

`mixin N<T...> on T1, ..., Tn implements I1, ..., Ik { ... }`

2. In dartLangSpec.tex:6065, the mixin interface M_I is defined as if
by:

`abstract class N<T...> implements T1, ..., Tn, I1, ..., Ik { ... }`

and dartLangSpec.tex:6078 says it is a compile-time error for the mixin
if that synthetic class declaration would be a compile-time error.

3. In dartLangSpec.tex:5189, class superinterfaces say:

It is a compile-time error if two elements in the type list of the
IMPLEMENTS clause of a class C specifies the same type T.

So:

`mixin M on A implements A {}`

is checked like:

`abstract class M implements A, A {}`

which violates the duplicate implements type rule.

Change-Id: I29e5fa17c47d111346ef6a6e321ab5dbab985ad1
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/503501
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Paul Berry <paulberry@google.com>
2026-05-18 07:55:50 -07:00
..
2026-05-15 09:28:17 -07:00

analysis_server

A long-running process that provides analysis results to other tools.

The analysis server is designed to provide on-going analysis of one or more code bases as those code bases are changing.

Using the server

The analysis server is not intended to be used stand-alone, and therefore does not have a human-friendly user interface.

Clients (typically tools, such as an editor) are expected to run the analysis server in a separate process and communicate with it using a JSON protocol. The original protocol is specified in the file analysis_server/doc/api.html and Language Server Protocol support is documented in tool/lsp_spec/README.md.

Features and bugs

Please file feature requests and bugs at the issue tracker.