[abashev]

Error Prone has run on every compile, but nothing it reported failed the build except two JUnit checks, and the warnings scrolled past. This is the first step towards making it fail the build: the suppressions go, and four checks become errors once their findings are fixed.

• @SuppressWarnings. 105 of the 110 are gone. They hid almost nothing. 94 named their checks with palantir-baseline's for-rollout: prefix, which plain Error Prone does not take for a check's name, so NullAway and the rest reported those lines all along. Others named checks this build does not run (TooManyArguments, ImmutablesStyle), IntelliJ inspections, or javac's unchecked lint, which is off. Removing UnicodeEscape's brings back its one finding.
• Immutable stays suppressed. The five suppressions on Doc's and Level's memoized suppliers remain. Immutable is an error by default, and the check is right: Suppliers.memoize caches its value, so Break, Token and NonBreakingSpace, which are @Immutable and extend Doc, are not immutable. Fixing that is a change of its own.
• Four checks are errors, after their findings are fixed. Each one has its own commit, and every commit builds. All the checks that fail the build are now set in one block; the ones that were only listed as comments for later are gone.
  • UnusedVariable: ExecutableTransform's logger, StringWrapper's endLine, and the stderr that two MainTest tests read after the process had exited.
  • SameNameButDifferent: in PalantirJavaFormatSettings, State named both IntelliJ's @State and the settings bean. The bean is now StoredSettings. Its class name is not stored in .idea/open-java-format.xml, and PalantirJavaFormatSettingsTest loads files written before.
  • RefactorSwitch: four switch statements that returned from every case are now the switch expressions they return.
  • FormatStringConcatenation: seven calls in the tests pass a format string and its arguments to AssertJ's describedAs, hasMessage and isEqualTo and to Guava's checkState, instead of a concatenated string. In JavaCommentsHelperTest the expected comment stays written out like its input, and the check is suppressed on that test.

Tests

./gradlew test passes on JDK 21: 1557 tests, 14 skipped. With an unused local added to CommandLineOptionsParser, :open-java-format:compileJava fails with error: [UnusedVariable].

Not here

166 warnings remain: NullAway 102, CollectorMutability 12, EffectivelyPrivate 12, StringConcatToTextBlock 9, ConstantNaming 5, and 1 to 3 each for 17 more checks. There are also 133 suggestions (StaticImport 86, LexicographicalAnnotationListing 23, and others). Those checks, Immutable included, follow one at a time.