A wrapper library and program that runs clang_tidy on the Flutter engine repo.
# Assuming you are in the `flutter` root of the engine repo. dart ./tools/clang_tidy/bin/main.dart
By default, the linter runs over modified[^1] files in the latest[^2] build of the engine.
A subset of checks can also be fixed automatically by passing --fix:
dart ./tools/clang_tidy/bin/main.dart --fix
To configure what lints are enabled, see .clang-tidy.
💡 TIP: If you're looking for the git pre-commit hook configuration, see
githooks.
Some common use cases are described below, or use --help to see all options.
To run adding a check not specified in .clang-tidy:
dart ./tools/clang_tidy/bin/main.dart --checks="<check-name-to-run>"
It's possible also to use wildcards to add multiple checks:
dart ./tools/clang_tidy/bin/main.dart --checks="readability-*"
To remove a specific check:
dart ./tools/clang_tidy/bin/main.dart --checks="-<check-name-to-remove>"
To remove multiple checks:
dart ./tools/clang_tidy/bin/main.dart --checks="-readability-*"
To remove all checks (usually to add a specific check):
dart ./tools/clang_tidy/bin/main.dart --checks="-*,<only-check-to-run>"
There are some rules that are only applicable to certain builds, or to check a difference in behavior between two builds.
Use --target-variant to specify a build:
dart ./tools/clang_tidy/bin/main.dart --target-variant <engine-variant>
For example, to check the android_debug_unopt build:
dart ./tools/clang_tidy/bin/main.dart --target-variant android_debug_unopt
In rarer cases, for example comparing two different checkouts of the engine, use --src-dir=<path/to/engine/src>.
When adding a new lint rule, or when checking lint rules that impact files that have not changed.
Use --lint-all to lint all files in the repo:
dart ./tools/clang_tidy/bin/main.dart --lint-all
Or, provide a regular expression to lint files that match:
dart ./tools/clang_tidy/bin/main.dart --lint-regex=".*test.*\.cc"
⚠️ WARNING: This may take a long time to run if a pattern is not provided or if the pattern matches a large number of files, i.e. on the order of thousands of files could take 30 minutes or more to run and lock your machine.
[^1]: Modified files are determined by a git diff command compared to HEAD. [^2]: Latest build is the last updated directory in src/out/.