In rare circumstances involving syntax errors, the `parsePattern` method inserts a synthetic token but does not consume any tokens. Usually when this happens it's not a problem, because whatever method is calling `parsePattern` consumes some tokens, so the parser always makes progress. However, when parsing list patterns, after calling `parsePattern`, the parser would look for a `,`, and if it didn't find one, it would supply a synthetic `,` and call `parsePattern` again, resulting in an infinite loop. A similar situation happened with map patterns, though the situation was more complex because in between the calls to `parsePattern`, the parser would also create synthetic key expressions and `:`s. To fix the problem, when parsing a list or map pattern, after the call to `parsePattern`, the parser checks whether any tokens were consumed. If no tokens were consumed, it ignores the next token from the input stream in order to make progress. I also investigated whether there were similar issues with parenthesized/record patterns and switch expressions, since those constructs also consist of a sequence of patterns separated by tokens and other things that could in principle be supplied synthetically. Fortunately, parser recovery doesn't get into an infinite loop in those cases, so I didn't make any further changes. But I did include test cases to make sure. Fixes #52352. Bug: https://github.com/dart-lang/sdk/issues/52352 Change-Id: Idc8140236f6054deb1fd3c862036fe47dd84f30b Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/302803 Reviewed-by: Konstantin Shcheglov <scheglov@google.com> Commit-Queue: Paul Berry <paulberry@google.com>
Package validation
The packages in pkg/ are automatically validated on the LUCI CI bots. The
validation is largely done by the tools/package_deps package; it can be tested
locally via:
dart tools/package_deps/bin/package_deps.dart
Packages which are published
There are several packages developed in pkg/ which are published to pub.
Validation of these packages is particularly important because the pub tools are
not used for these packages during development; we get our dependency versions
from the DEPS file. Its very easy for the dependencies specified in a package's
pubspec file to get out of date wrt the packages and versions actually used.
In order to better ensure we're publishing correct packages, we validate some properties of the pubspec files on our CI system. These validations include:
- that the dependencies listed in the pubspec are used in the package
- that all the packages used by the source are listed in the pubspec
- that we don't use relative path deps to pkg/ or third_party/ packages
Packages which are not published
For packages in pkg/ which we do not intend to be published, we put the following comment in the pubspec.yaml file:
# This package is not intended for consumption on pub.dev. DO NOT publish.
publish_to: none
These pubspecs are still validated by the package validation tool. The contents are more informational as the pubspecs for these packages are not consumed by the pub tool or ecosystem.
We validate:
- that the dependencies listed in the pubspec are used in the package
- that all the packages used by the source are listed in the pubspec
- that a reference to a pkg/ package is done via a relative path dependency