Only run clang-tidy warning checks reported as errors

Author: jmagman

.clang-tidy

@@ -2,7 +2,8 @@
 Checks: "bugprone-use-after-move,\
 clang-analyzer-*,\
 clang-diagnostic-*,\
-google-*,\
+google-objc-*,\
+google-explicit-constructor" \
 modernize-use-default-member-init,\
 readability-identifier-naming,\
 -google-objc-global-variable-declaration,\
@@ -14,18 +15,6 @@ readability-identifier-naming,\
 performance-move-const-arg,\
 performance-unnecessary-value-param"
 
-# Only warnings treated as errors are reported
-# in the "ci/lint.sh" script and pre-push git hook.
-# Add checks when all warnings are fixed
-# to prevent new warnings being introduced.
-# https://github.com/flutter/flutter/issues/93279
-WarningsAsErrors: "bugprone-use-after-move,\
-clang-analyzer-*,\
-readability-identifier-naming,\
-clang-diagnostic-*,\
-google-objc-*,\
-google-explicit-constructor"
-
 CheckOptions:
   - key:    modernize-use-default-member-init.UseAssignment
     value:  true

tools/clang_tidy/lib/clang_tidy.dart

@@ -46,6 +46,7 @@ class ClangTidy {
   ClangTidy({
     required io.File buildCommandsPath,
     String checksArg = '',
+    bool warningsAsErrors = false,
     bool lintAll = false,
     bool lintHead = false,
     bool fix = false,
@@ -55,6 +56,7 @@ class ClangTidy {
     options = Options(
       buildCommandsPath: buildCommandsPath,
       checksArg: checksArg,
+      warningsAsErrors: warningsAsErrors,
       lintAll: lintAll,
       lintHead: lintHead,
       fix: fix,
@@ -99,6 +101,9 @@ class ClangTidy {
       if (options.checksArg.isNotEmpty) {
         _outSink.writeln('Checking for specific checks: ${options.checks}.');
       }
+      if (options.warningsAsErrors) {
+        _outSink.writeln('Treating warnings as errors.');
+      }
       final int changedFilesCount = changedFiles.length;
       if (options.lintAll) {
         _outSink.writeln('Checking all $changedFilesCount files the repo dir.');
@@ -136,6 +141,7 @@ class ClangTidy {
       changedFileBuildCommands,
       options.repoPath,
       options.checks,
+      options.warningsAsErrors,
     );
     final int computeResult = computeJobsResult.sawMalformed ? 1 : 0;
     final List<WorkerJob> jobs = computeJobsResult.jobs;
@@ -195,6 +201,7 @@ class ClangTidy {
     List<Command> commands,
     io.Directory repoPath,
     String? checks,
+    bool warningsAsErrors,
   ) async {
     bool sawMalformed = false;
     final List<WorkerJob> jobs = <WorkerJob>[];
@@ -217,7 +224,11 @@ class ClangTidy {
           break;
         case LintAction.lint:
           _outSink.writeln('🔶 linting $relativePath');
-          jobs.add(command.createLintJob(checks, options.fix));
+          jobs.add(command.createLintJob(
+            checks: checks,
+            warningsAsErrors: warningsAsErrors,
+            fix: options.fix,
+          ));
           break;
         case LintAction.skipThirdParty:
           _outSink.writeln('🔷 ignoring $relativePath (third_party)');

tools/clang_tidy/lib/src/command.dart

@@ -129,11 +129,19 @@ class Command {
   }
 
   /// The job for the process runner for the lint needed for this command.
-  WorkerJob createLintJob(String? checks, bool fix) {
+  WorkerJob createLintJob({
+    String? checks,
+    bool warningsAsErrors = false,
+    bool fix = false,
+  }) {
     final List<String> args = <String>[
       filePath,
       if (checks != null)
         checks,
+      if (warningsAsErrors) ...<String>[
+        '--warnings-as-errors',
+        '*',
+      ],
       if (fix) ...<String>[
         '--fix',
         '--format-style=file',

tools/clang_tidy/lib/src/options.dart

@@ -19,6 +19,7 @@ class Options {
     this.help = false,
     this.verbose = false,
     this.checksArg = '',
+    this.warningsAsErrors = false,
     this.lintAll = false,
     this.lintHead = false,
     this.fix = false,
@@ -59,6 +60,7 @@ class Options {
       verbose: options['verbose'] as bool,
       buildCommandsPath: buildCommandsPath,
       checksArg: options.wasParsed('checks') ? options['checks'] as String : '',
+      warningsAsErrors: options['warnings-as-errors'] as bool? ?? false,
       lintAll: io.Platform.environment['FLUTTER_LINT_ALL'] != null ||
                options['lint-all'] as bool,
       lintHead: options['lint-head'] as bool,
@@ -120,6 +122,11 @@ class Options {
       'verbose',
       help: 'Print verbose output.',
     )
+    ..addFlag(
+      'warnings-as-errors',
+      help: 'Treat all warnings as errors.',
+      defaultsTo: true,
+    )
     ..addOption(
       'compile-commands',
       help: 'Use the given path as the source of compile_commands.json. This '
@@ -166,6 +173,9 @@ class Options {
   /// Check arguments to plumb through to clang-tidy.
   final String? checks;
 
+  /// Surface all warnings as errors.
+  final bool warningsAsErrors;
+
   /// Whether all files should be linted.
   final bool lintAll;
 

tools/clang_tidy/test/clang_tidy_test.dart

@@ -228,21 +228,30 @@ Future<int> main(List<String> args) async {
     expect(commands, isNotEmpty);
     final Command command = commands.first;
     expect(command.tidyPath, contains('clang/bin/clang-tidy'));
-    final WorkerJob jobNoFix = command.createLintJob(null, false);
+    final WorkerJob jobNoFix = command.createLintJob();
     expect(jobNoFix.command[0], endsWith('../../buildtools/mac-x64/clang/bin/clang-tidy'));
     expect(jobNoFix.command[1], endsWith(filePath.replaceAll('/', io.Platform.pathSeparator)));
     expect(jobNoFix.command[2], '--');
     expect(jobNoFix.command[3], '');
     expect(jobNoFix.command[4], endsWith(filePath));
 
-    final WorkerJob jobWithFix = command.createLintJob(null, true);
+    final WorkerJob jobWithFix = command.createLintJob(fix: true);
     expect(jobWithFix.command[0], endsWith('../../buildtools/mac-x64/clang/bin/clang-tidy'));
     expect(jobWithFix.command[1], endsWith(filePath.replaceAll('/', io.Platform.pathSeparator)));
     expect(jobWithFix.command[2], '--fix');
     expect(jobWithFix.command[3], '--format-style=file');
     expect(jobWithFix.command[4], '--');
     expect(jobWithFix.command[5], '');
     expect(jobWithFix.command[6], endsWith(filePath));
+
+    final WorkerJob jobWithWarning = command.createLintJob(warningsAsErrors: true);
+    expect(jobWithWarning.command[0], endsWith('../../buildtools/mac-x64/clang/bin/clang-tidy'));
+    expect(jobWithWarning.command[1], endsWith(filePath.replaceAll('/', io.Platform.pathSeparator)));
+    expect(jobWithWarning.command[2], '--warnings-as-errors');
+    expect(jobWithWarning.command[3], '*');
+    expect(jobWithWarning.command[4], '--');
+    expect(jobWithWarning.command[5], '');
+    expect(jobWithWarning.command[6], endsWith(filePath));
   });
 
   test('Command getLintAction flags third_party files', () async {