feat: add support for filtering test optimization (#1377)

Author: matiasleyba

bricks/test_optimizer/hooks/lib/pre_gen.dart

@@ -8,6 +8,12 @@ typedef ExitFn = Never Function(int code);
 
 ExitFn exitFn = exit;
 
+String skipVeryGoodOptimizationTag = 'skip_very_good_optimization';
+RegExp skipVeryGoodOptimizationRegExp = RegExp(
+  "@Tags\\s*\\(\\s*\\[[\\s\\S]*?[\"']$skipVeryGoodOptimizationTag[\"'][\\s\\S]*?\\]\\s*\\)",
+  multiLine: true,
+);
+
 Future<void> run(HookContext context) async {
   final packageRoot = context.vars['package-root'] as String;
   final testDir = Directory(path.join(packageRoot, 'test'));
@@ -29,8 +35,13 @@ Future<void> run(HookContext context) async {
 
   final identifierGenerator = DartIdentifierGenerator();
   final testIdentifierTable = <Map<String, String>>[];
-  for (final entity
-      in testDir.listSync(recursive: true).where((entity) => entity.isTest)) {
+  final tests = testDir
+      .listSync(recursive: true)
+      .where((entity) => entity.isTest);
+
+  final notOptimizedTests = await getNotOptimizedTests(tests, testDir.path);
+
+  for (final entity in tests) {
     final relativePath = path
         .relative(entity.path, from: testDir.path)
         .replaceAll(r'\', '/');
@@ -40,11 +51,52 @@ Future<void> run(HookContext context) async {
     });
   }
 
-  context.vars = {'tests': testIdentifierTable, 'isFlutter': isFlutter};
+  final optimizedTestsIdentifierTable = testIdentifierTable
+      .where((e) => !notOptimizedTests.contains(e['path']))
+      .toList();
+
+  context.vars = {
+    'tests': optimizedTestsIdentifierTable,
+    'isFlutter': isFlutter,
+    'notOptimizedTests': notOptimizedTests,
+  };
 }
 
 extension on FileSystemEntity {
   bool get isTest {
     return this is File && path.basename(this.path).endsWith('_test.dart');
   }
 }
+
+Future<List<String>> getNotOptimizedTests(
+  Iterable<FileSystemEntity> tests,
+  String testDir,
+) async {
+  final paths = tests.map((e) => e.path).toList();
+  final formattedPaths = paths.map((e) => e.replaceAll('/./', '/')).toList();
+
+  final fileFutures = formattedPaths.map(_checkFileForSkipVeryGoodOptimization);
+  final fileResults = await Future.wait(fileFutures);
+
+  final testWithVeryGoodTest = <String>[];
+  for (var i = 0; i < formattedPaths.length; i++) {
+    if (fileResults[i]) {
+      testWithVeryGoodTest.add(formattedPaths[i]);
+    }
+  }
+
+  /// Format to relative path
+  final relativePaths = testWithVeryGoodTest
+      .map((e) => path.relative(e, from: testDir))
+      .toList();
+
+  return relativePaths;
+}
+
+/// Check if a single file contains skip_very_good_optimization tag
+Future<bool> _checkFileForSkipVeryGoodOptimization(String path) async {
+  final file = File(path);
+  if (!file.existsSync()) return false;
+  final content = await file.readAsString();
+  return skipVeryGoodOptimizationRegExp.hasMatch(content);
+}

bricks/test_optimizer/hooks/test/pre_gen_test.dart

@@ -16,6 +16,26 @@ class _FakeContext extends Fake implements HookContext {
   Map<String, Object?> vars = {};
 }
 
+final notOptimizedTestContent =
+    '''
+@Tags(['${pre_gen.skipVeryGoodOptimizationTag}'])
+void main() {
+  test('test', () {
+    expect(1, 1);
+  });
+}
+''';
+
+final anotherNotOptimizedTestContent =
+    '''
+@Tags(['${pre_gen.skipVeryGoodOptimizationTag}', 'another_tag'])
+void main() {
+  test('another test', () {
+    expect(1, 1);
+  });
+}
+''';
+
 void main() {
   late Directory tempDirectory;
 
@@ -86,6 +106,57 @@ dependencies:
 
         expect(context.vars['isFlutter'], true);
       });
+
+      test('with proper not optimized tests identification', () async {
+        File(path.join(tempDirectory.path, 'pubspec.yaml')).createSync();
+
+        final testDir = Directory(path.join(tempDirectory.path, 'test'))
+          ..createSync();
+        File(path.join(testDir.path, 'test1_test.dart')).createSync();
+        File(path.join(testDir.path, 'test2_test.dart')).createSync();
+        File(path.join(testDir.path, 'no_test_here.dart')).createSync();
+        File(
+          path.join(testDir.path, 'not_optimized_test.dart'),
+        ).writeAsStringSync(notOptimizedTestContent);
+        File(
+          path.join(testDir.path, 'another_not_optimized_test.dart'),
+        ).writeAsStringSync(anotherNotOptimizedTestContent);
+
+        context.vars['package-root'] = tempDirectory.absolute.path;
+
+        await pre_gen.run(context);
+
+        final tests = context.vars['tests'] as List<Map<String, String>>;
+        final testsMap = <String, String>{};
+        for (final test in tests) {
+          final path = test['path']!;
+          final identifier = test['identifier']!;
+          testsMap[path] = identifier;
+        }
+
+        final paths = testsMap.keys;
+        expect(paths, contains('test1_test.dart'));
+        expect(paths, contains('test2_test.dart'));
+        expect(paths, isNot(contains('no_test_here.dart')));
+        expect(paths, isNot(contains('not_optimized_test.dart')));
+        expect(paths, isNot(contains('another_not_optimized_test.dart')));
+
+        expect(
+          testsMap.values.toSet().length,
+          equals(tests.length),
+          reason: 'All tests files should have unique identifiers',
+        );
+        final notOptimizedTests =
+            context.vars['notOptimizedTests'] as List<String>;
+        expect(
+          notOptimizedTests,
+          contains('not_optimized_test.dart'),
+        );
+        expect(
+          notOptimizedTests,
+          contains('another_not_optimized_test.dart'),
+        );
+      });
     });
 
     group('Fails', () {
@@ -155,5 +226,65 @@ dependencies:
         expect(context.vars['isFlutter'], isNull);
       });
     });
+
+    group('skipVeryGoodOptimizationRegExp regex', () {
+      final regex = pre_gen.skipVeryGoodOptimizationRegExp;
+      test('matches single-line tag', () {
+        final content = "@Tags(['${pre_gen.skipVeryGoodOptimizationTag}'])";
+        expect(regex.hasMatch(content), isTrue);
+      });
+
+      test('matches single-line with multiple tags', () {
+        final content =
+            "@Tags(['${pre_gen.skipVeryGoodOptimizationTag}', 'chrome'])";
+        expect(regex.hasMatch(content), isTrue);
+      });
+
+      test('matches multi-line tag list', () {
+        final content =
+            '''
+      @Tags([
+        '${pre_gen.skipVeryGoodOptimizationTag}',
+        'chrome',
+        'test',
+      ])
+      ''';
+        expect(regex.hasMatch(content), isTrue);
+      });
+
+      test('matches multi-line where tag is not the first', () {
+        final content =
+            '''
+      @Tags([
+        'chrome',
+        '${pre_gen.skipVeryGoodOptimizationTag}',
+        'test',
+      ])
+      ''';
+        expect(regex.hasMatch(content), isTrue);
+      });
+
+      test('does not match when tag missing', () {
+        const content = "@Tags(['chrome', 'test'])";
+        expect(regex.hasMatch(content), isFalse);
+      });
+
+      test(
+        'does not match substring only (e.g. skip_very_good_optimization,test)',
+        () {
+          final content =
+              '''
+      @Tags([
+        '${pre_gen.skipVeryGoodOptimizationTag},test',
+        'chrome',
+      ])
+      ''';
+          expect(
+            regex.hasMatch(content),
+            isFalse,
+          ); // only exact tag should match
+        },
+      );
+    });
   });
 }