[flutter_tools] According to AnalysisSeverity return exit code detailed proposal (#61589)

No matter what level(error, warning, info) issues flutter analyze always return fatal exit code(1). CI/CD environment receive 1(!0). This may leads to e.g. Jenkins Build step 'Execute shell' marked build as failure.
I propose according to AnalysisSeverity level return fatal(1) or success(0) exit code.

packages/flutter_tools/lib/src/commands/analyze.dart

@@ -73,6 +73,14 @@ class AnalyzeCommand extends FlutterCommand {
         help: 'When analyzing the flutter repository, display the number of '
               'files that will be analyzed.\n'
               'Ignored if --watch is specified.');
+    argParser.addFlag('fatal-infos',
+        negatable: true,
+        help: 'Treat info level issues as fatal.',
+        defaultsTo: true);
+    argParser.addFlag('fatal-warnings',
+        negatable: true,
+        help: 'Treat warning level issues as fatal.',
+        defaultsTo: true);
   }
 
   /// The working directory for testing analysis using dartanalyzer.

packages/flutter_tools/lib/src/commands/analyze_once.dart

@@ -182,8 +182,7 @@ class AnalyzeOnce extends AnalyzeBase {
 
     if (errorCount > 0) {
       logger.printStatus('');
-      // We consider any level of error to be an error exit (we don't report different levels).
-      throwToolExit(errorsMessage);
+      throwToolExit(errorsMessage, exitCode: _isFatal(errors) ? 1 : 0);
     }
 
     if (argResults['congratulate'] as bool) {
@@ -194,4 +193,21 @@ class AnalyzeOnce extends AnalyzeBase {
       throwToolExit('Server error(s) occurred. (ran in ${seconds}s)');
     }
   }
+
+  bool _isFatal(List<AnalysisError> errors) {
+    for (final AnalysisError error in errors) {
+      final AnalysisSeverity severityLevel = error.writtenError.severityLevel;
+      if (severityLevel == AnalysisSeverity.error) {
+        return true;
+      }
+      if (severityLevel == AnalysisSeverity.warning &&
+        (argResults['fatal-warnings'] as bool || argResults['fatal-infos'] as bool)) {
+        return true;
+      }
+      if (severityLevel == AnalysisSeverity.info && argResults['fatal-infos'] as bool) {
+        return true;
+      }
+    }
+    return false;
+  }
 }

packages/flutter_tools/lib/src/dart/analysis.dart

@@ -190,7 +190,7 @@ class AnalysisServer {
   }
 }
 
-enum _AnalysisSeverity {
+enum AnalysisSeverity {
   error,
   warning,
   info,
@@ -217,12 +217,12 @@ class AnalysisError implements Comparable<AnalysisError> {
 
   String get colorSeverity {
     switch (writtenError.severityLevel) {
-      case _AnalysisSeverity.error:
+      case AnalysisSeverity.error:
         return _terminal.color(writtenError.severity, TerminalColor.red);
-      case _AnalysisSeverity.warning:
+      case AnalysisSeverity.warning:
         return _terminal.color(writtenError.severity, TerminalColor.yellow);
-      case _AnalysisSeverity.info:
-      case _AnalysisSeverity.none:
+      case AnalysisSeverity.info:
+      case AnalysisSeverity.none:
         return writtenError.severity;
     }
     return null;
@@ -316,14 +316,14 @@ class WrittenError {
   final int startColumn;
   final int offset;
 
-  static final Map<String, _AnalysisSeverity> _severityMap = <String, _AnalysisSeverity>{
-    'INFO': _AnalysisSeverity.info,
-    'WARNING': _AnalysisSeverity.warning,
-    'ERROR': _AnalysisSeverity.error,
+  static final Map<String, AnalysisSeverity> _severityMap = <String, AnalysisSeverity>{
+    'INFO': AnalysisSeverity.info,
+    'WARNING': AnalysisSeverity.warning,
+    'ERROR': AnalysisSeverity.error,
   };
 
-  _AnalysisSeverity get severityLevel =>
-      _severityMap[severity] ?? _AnalysisSeverity.none;
+  AnalysisSeverity get severityLevel =>
+      _severityMap[severity] ?? AnalysisSeverity.none;
 
   String get messageSentenceFragment {
     if (message.endsWith('.')) {

packages/flutter_tools/test/commands.shard/permeable/analyze_once_test.dart

@@ -41,6 +41,7 @@ void main() {
     List<String> errorTextContains,
     bool toolExit = false,
     String exitMessageContains,
+    int exitCode = 0,
   }) async {
     try {
       arguments.insert(0, '--flutter-root=${Cache.flutterRoot}');
@@ -53,6 +54,8 @@ void main() {
       }
       if (exitMessageContains != null) {
         expect(e.message, contains(exitMessageContains));
+        // May not analyzer exception the `exitCode` is `null`.
+        expect(e.exitCode ?? 0, exitCode);
       }
     }
     assertContains(logger.statusText, statusTextContains);
@@ -194,6 +197,7 @@ flutter_project:lib/
       ],
       exitMessageContains: '3 issues found.',
       toolExit: true,
+      exitCode: 1,
     );
   });
 
@@ -239,6 +243,7 @@ flutter_project:lib/
         ],
         exitMessageContains: '2 issues found.',
         toolExit: true,
+        exitCode: 1,
       );
     } finally {
       if (optionsFile.existsSync()) {
@@ -284,6 +289,7 @@ void bar() {
         ],
         exitMessageContains: '1 issue found.',
         toolExit: true,
+        exitCode: 1
       );
     } finally {
       tryToDelete(tempDir);
@@ -371,12 +377,157 @@ StringBuffer bar = StringBuffer('baz');
       tryToDelete(tempDir);
     }
   });
+
+  testUsingContext('analyze once with default options has info issue finally exit code 1.', () async {
+    final Directory tempDir = fileSystem.systemTempDirectory.createTempSync(
+        'flutter_analyze_once_default_options_info_issue_exit_code_1.');
+    _createDotPackages(tempDir.path);
+
+    const String infoSourceCode = '''
+int analyze() {}
+''';
+
+    tempDir.childFile('main.dart').writeAsStringSync(infoSourceCode);
+    try {
+      await runCommand(
+        command: AnalyzeCommand(
+          workingDirectory: fileSystem.directory(tempDir),
+          platform: _kNoColorTerminalPlatform,
+          terminal: terminal,
+          processManager: processManager,
+          logger: logger,
+          fileSystem: fileSystem,
+          artifacts: artifacts,
+        ),
+        arguments: <String>['analyze', '--no-pub'],
+        statusTextContains: <String>[
+          'info',
+          'missing_return',
+        ],
+        exitMessageContains: '1 issue found.',
+        toolExit: true,
+        exitCode: 1,
+      );
+    } finally {
+      tryToDelete(tempDir);
+    }
+  });
+
+  testUsingContext('analyze once with no-fatal-infos has info issue finally exit code 0.', () async {
+    final Directory tempDir = fileSystem.systemTempDirectory.createTempSync(
+        'flutter_analyze_once_no_fatal_infos_info_issue_exit_code_0.');
+    _createDotPackages(tempDir.path);
+
+    const String infoSourceCode = '''
+int analyze() {}
+''';
+
+    tempDir.childFile('main.dart').writeAsStringSync(infoSourceCode);
+    try {
+      await runCommand(
+        command: AnalyzeCommand(
+          workingDirectory: fileSystem.directory(tempDir),
+          platform: _kNoColorTerminalPlatform,
+          terminal: terminal,
+          processManager: processManager,
+          logger: logger,
+          fileSystem: fileSystem,
+          artifacts: artifacts,
+        ),
+        arguments: <String>['analyze', '--no-pub', '--no-fatal-infos'],
+        statusTextContains: <String>[
+          'info',
+          'missing_return',
+        ],
+        exitMessageContains: '1 issue found.',
+        toolExit: true,
+        exitCode: 0,
+      );
+    } finally {
+      tryToDelete(tempDir);
+    }
+  });
+
+  testUsingContext('analyze once only fatal-warnings has info issue finally exit code 0.', () async {
+    final Directory tempDir = fileSystem.systemTempDirectory.createTempSync(
+        'flutter_analyze_once_only_fatal_warnings_info_issue_exit_code_0.');
+    _createDotPackages(tempDir.path);
+
+    const String infoSourceCode = '''
+int analyze() {}
+''';
+
+    tempDir.childFile('main.dart').writeAsStringSync(infoSourceCode);
+    try {
+      await runCommand(
+        command: AnalyzeCommand(
+          workingDirectory: fileSystem.directory(tempDir),
+          platform: _kNoColorTerminalPlatform,
+          terminal: terminal,
+          processManager: processManager,
+          logger: logger,
+          fileSystem: fileSystem,
+          artifacts: artifacts,
+        ),
+        arguments: <String>['analyze', '--no-pub', '--fatal-warnings', '--no-fatal-infos'],
+        statusTextContains: <String>[
+          'info',
+          'missing_return',
+        ],
+        exitMessageContains: '1 issue found.',
+        toolExit: true,
+        exitCode: 0,
+      );
+    } finally {
+      tryToDelete(tempDir);
+    }
+  });
+
+  testUsingContext('analyze once only fatal-infos has warning issue finally exit code 1.', () async {
+    final Directory tempDir = fileSystem.systemTempDirectory.createTempSync(
+        'flutter_analyze_once_only_fatal_infos_warning_issue_exit_code_1.');
+    _createDotPackages(tempDir.path);
+
+    const String warningSourceCode = '''
+int analyze() {}
+''';
+
+    final File optionsFile = fileSystem.file(fileSystem.path.join(tempDir.path, 'analysis_options.yaml'));
+    optionsFile.writeAsStringSync('''
+analyzer:
+  errors:
+    missing_return: warning
+  ''');
+
+    tempDir.childFile('main.dart').writeAsStringSync(warningSourceCode);
+    try {
+      await runCommand(
+        command: AnalyzeCommand(
+          workingDirectory: fileSystem.directory(tempDir),
+          platform: _kNoColorTerminalPlatform,
+          terminal: terminal,
+          processManager: processManager,
+          logger: logger,
+          fileSystem: fileSystem,
+          artifacts: artifacts,
+        ),
+        arguments: <String>['analyze','--no-pub', '--fatal-infos', '--no-fatal-warnings'],
+        statusTextContains: <String>[
+          'warning',
+          'missing_return',
+        ],
+        exitMessageContains: '1 issue found.',
+        toolExit: true,
+        exitCode: 1,
+      );
+    } finally {
+      tryToDelete(tempDir);
+    }
+  });
 }
 
 void assertContains(String text, List<String> patterns) {
-  if (patterns == null) {
-    expect(text, isEmpty);
-  } else {
+  if (patterns != null) {
     for (final String pattern in patterns) {
       expect(text, contains(pattern));
     }