Add pre-commit hook to verify static analysis passes & format is correct

script/githooks/bin/install_hooks.dart

@@ -0,0 +1,32 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// ignore_for_file: avoid_print
+
+import 'dart:io';
+import 'package:path/path.dart' as p;
+
+void main() async {
+  Directory repoRoot = Directory.current;
+  while (repoRoot.path != '/' && !Directory(p.join(repoRoot.path, '.git')).existsSync()) {
+    repoRoot = repoRoot.parent;
+  }
+
+  if (repoRoot.path == '/') {
+    print('❌ Could not find .git directory.');
+    exit(1);
+  }
+
+  final ProcessResult result = await Process.run('git', [
+    'config',
+    'core.hooksPath',
+    'script/githooks',
+  ], workingDirectory: repoRoot.path);
+  if (result.exitCode == 0) {
+    print('✅ Git hooks installed successfully!');
+  } else {
+    print('❌ Failed to install Git hooks: ${result.stderr}');
+    exit(1);
+  }
+}

script/githooks/bin/main.dart

@@ -0,0 +1,11 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:io' as io;
+
+import 'package:githooks/githooks.dart';
+
+Future<void> main(List<String> args) async {
+  io.exitCode = await run(args);
+}

script/githooks/lib/githooks.dart

@@ -0,0 +1,16 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:args/command_runner.dart';
+
+import 'src/pre_commit_command.dart';
+
+/// Runs the githooks command line utility.
+Future<int> run(List<String> args) async {
+  final runner = CommandRunner<bool>('githooks', 'Git hooks for flutter/packages')
+    ..addCommand(PreCommitCommand());
+
+  final bool success = await runner.run(args) ?? false;
+  return success ? 0 : 1;
+}

script/githooks/lib/src/pre_commit_command.dart

@@ -0,0 +1,158 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// ignore_for_file: avoid_print
+
+import 'dart:io';
+import 'package:args/command_runner.dart';
+import 'package:path/path.dart' as p;
+
+/// The command that implements the pre-commit githook.
+class PreCommitCommand extends Command<bool> {
+  /// Creates a [PreCommitCommand].
+  PreCommitCommand({
+    Future<ProcessResult> Function(
+      String executable,
+      List<String> arguments, {
+      String? workingDirectory,
+    })?
+    processRunner,
+  }) : processRunner = processRunner ?? Process.run;
+
+  /// The process runner injected for testing.
+  final Future<ProcessResult> Function(
+    String executable,
+    List<String> arguments, {
+    String? workingDirectory,
+  })
+  processRunner;
+
+  @override
+  final String name = 'pre-commit';
+
+  @override
+  final String description = 'Checks to run before a "git commit"';
+
+  String? _findPackageName(String filePath, String repoRoot) {
+    Directory currentDir = File(p.join(repoRoot, filePath)).parent;
+    while (p.isWithin(repoRoot, currentDir.path) || p.equals(repoRoot, currentDir.path)) {
+      final String dirName = p.basename(currentDir.path);
+      if (dirName != 'example' && File(p.join(currentDir.path, 'pubspec.yaml')).existsSync()) {
+        return dirName;
+      }
+      if (p.equals(repoRoot, currentDir.path)) {
+        break;
+      }
+      currentDir = currentDir.parent;
+    }
+    return null;
+  }
+
+  @override
+  Future<bool> run() async {
+    // Find the repo root where the plugin tool is located.
+    Directory repoRoot = Directory.current;
+    while (repoRoot.path != '/' && !Directory(p.join(repoRoot.path, '.git')).existsSync()) {
+      repoRoot = repoRoot.parent;
+    }
+
+    if (repoRoot.path == '/') {
+      print('❌ Could not find .git directory.');
+      return false;
+    }
+
+    final ProcessResult diffResult = await processRunner('git', [
+      'diff',
+      '--cached',
+      '--name-only',
+      '--diff-filter=ACM',
+    ], workingDirectory: repoRoot.path);
+
+    if (diffResult.exitCode != 0) {
+      print('❌ Failed to get staged files');
+      return false;
+    }
+
+    final List<String> stagedFiles = (diffResult.stdout as String)
+        .split('\n')
+        .map((e) => e.trim())
+        .where((e) => e.isNotEmpty)
+        .toList();
+
+    if (stagedFiles.isEmpty) {
+      return true; // No files changed.
+    }
+
+    final Set<String> targetPackages = {};
+    for (final file in stagedFiles) {
+      final String? packageName = _findPackageName(file, repoRoot.path);
+      if (packageName != null) {
+        targetPackages.add(packageName);
+      }
+    }
+
+    if (targetPackages.isEmpty) {
+      return true; // None of the changed files are part of a package we care about.
+    }
+
+    final String toolScript = p.join(
+      repoRoot.path,
+      'script',
+      'tool',
+      'bin',
+      'flutter_plugin_tools.dart',
+    );
+    final packageArgs = '--packages=${targetPackages.join(',')}';
+
+    print(
+      '🔍 Running pre-commit checks on ${targetPackages.length} packages: ${targetPackages.join(', ')}',
+    );
+    var hasError = false;
+
+    // Check formatting.
+    print('Checking formatting...');
+    final ProcessResult formatResult = await processRunner('dart', [
+      'run',
+      toolScript,
+      'format',
+      packageArgs,
+      '--fail-on-change',
+    ], workingDirectory: repoRoot.path);
+
+    if (formatResult.exitCode != 0) {
+      if (formatResult.stdout.toString().isNotEmpty) {
+        print(formatResult.stdout);
+      }
+      if (formatResult.stderr.toString().isNotEmpty) {
+        print(formatResult.stderr);
+      }
+      print(
+        '❌ Formatting issues found. Please run "dart run script/tool/bin/flutter_plugin_tools.dart format $packageArgs" to fix them.',
+      );
+      hasError = true;
+    } else {
+      print('✅ Formatting looks good.');
+    }
+
+    // Run static analysis.
+    print('Running static analysis...');
+    final ProcessResult analyzeResult = await processRunner('dart', [
+      'run',
+      toolScript,
+      'analyze',
+      packageArgs,
+    ], workingDirectory: repoRoot.path);
+
+    if (analyzeResult.exitCode != 0) {
+      if (analyzeResult.stdout.toString().isNotEmpty) print(analyzeResult.stdout);
+      if (analyzeResult.stderr.toString().isNotEmpty) print(analyzeResult.stderr);
+      print('❌ Static analysis errors found. Please fix the errors listed above.');
+      hasError = true;
+    } else {
+      print('✅ Static analysis looks good.');
+    }
+
+    return !hasError;
+  }
+}

script/githooks/pre-commit

@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+set -e
+
+HOOKS_DIR="$(dirname "$0")"
+exec dart "$HOOKS_DIR/bin/main.dart" pre-commit "$@"

script/githooks/pubspec.yaml

@@ -0,0 +1,13 @@
+name: githooks
+description: Git hooks for the flutter/packages repository.
+publish_to: none
+
+environment:
+  sdk: ^3.10.0-0
+
+dependencies:
+  args: any
+  path: any
+
+dev_dependencies:
+  test: any

script/githooks/test/pre_commit_test.dart

@@ -0,0 +1,78 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:io';
+
+import 'package:githooks/src/pre_commit_command.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('pre-commit hook', () {
+    test('passes when both format and analyze succeed', () async {
+      final command = PreCommitCommand(
+        processRunner:
+            (String executable, List<String> arguments, {String? workingDirectory}) async {
+              if (executable == 'git') {
+                return ProcessResult(0, 0, 'script/githooks/lib/githooks.dart\n', '');
+              }
+              return ProcessResult(0, 0, 'Success', '');
+            },
+      );
+
+      final bool result = await command.run();
+      expect(result, isTrue);
+    });
+
+    test('fails when formatting fails', () async {
+      final command = PreCommitCommand(
+        processRunner:
+            (String executable, List<String> arguments, {String? workingDirectory}) async {
+              if (executable == 'git') {
+                return ProcessResult(0, 0, 'script/githooks/lib/githooks.dart\n', '');
+              }
+              if (arguments.contains('format')) {
+                return ProcessResult(0, 1, 'bad_file.dart', '');
+              }
+              return ProcessResult(0, 0, 'Success', '');
+            },
+      );
+
+      final bool result = await command.run();
+      expect(result, isFalse);
+    });
+
+    test('fails when analysis fails', () async {
+      final command = PreCommitCommand(
+        processRunner:
+            (String executable, List<String> arguments, {String? workingDirectory}) async {
+              if (executable == 'git') {
+                return ProcessResult(0, 0, 'script/githooks/lib/githooks.dart\n', '');
+              }
+              if (arguments.contains('analyze')) {
+                return ProcessResult(0, 1, 'error in file.dart', '');
+              }
+              return ProcessResult(0, 0, 'Success', '');
+            },
+      );
+
+      final bool result = await command.run();
+      expect(result, isFalse);
+    });
+
+    test('ignores non-dart files', () async {
+      final command = PreCommitCommand(
+        processRunner:
+            (String executable, List<String> arguments, {String? workingDirectory}) async {
+              if (executable == 'git') {
+                return ProcessResult(0, 0, 'README.md\n', '');
+              }
+              return ProcessResult(0, 0, 'Success', '');
+            },
+      );
+
+      final bool result = await command.run();
+      expect(result, isTrue);
+    });
+  });
+}