Add support for keeping parser diagnostic expectations in the source
snippets they describe. Expectations are written as caret markers and
diagnostic comments, and regenerated from the parser's actual
diagnostics before comparison.
This keeps parser recovery expectations close to the code under test and
removes the need to maintain offset-based `assertErrors` lists by hand.
The updater also removes existing expectation markers before writing the
canonical form, so marked snippets can be refreshed in place.
Migrate recovery parser and class parser tests to the new
`assertExpectedDiagnostics` helper, including no-error cases where an
unmarked snippet is the expected canonical form.
Update `test_runner` to exclude `/pkg/analyzer/` from searching static
error expectations.
Bug: https://github.com/dart-lang/sdk/issues/63335
Change-Id: Ic9866da8cc601c6b360552ba576e8aa1646f89a5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/501340
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Paul Berry <paulberry@google.com>
Reviewed-by: Bob Nystrom <rnystrom@google.com>
Konstantin Shcheglov
1aa7d7321f