[flutter_tools] prevent wildcard assets from causing build invalidation issues (flutter#56472)

Author: jonahwilliams

packages/flutter_tools/lib/src/asset.dart

@@ -272,6 +272,19 @@ class ManifestAssetBundle implements AssetBundle {
     final DevFSStringContent licenses = DevFSStringContent(licenseResult.combinedLicenses);
     additionalDependencies = licenseResult.dependencies;
 
+    if (wildcardDirectories.isNotEmpty) {
+      // Force the depfile to contain missing files so that Gradle does not skip
+      // the task. Wildcard directories are not compatible with full incremental
+      // builds. For more context see https://github.com/flutter/flutter/issues/56466 .
+      globals.printTrace(
+        'Manifest contained wildcard assets. Inserting missing file into '
+        'build graph to force rerun. for more information see #56466.'
+      );
+      final int suffix = Object().hashCode;
+      additionalDependencies.add(
+        globals.fs.file('DOES_NOT_EXIST_RERUN_FOR_WILDCARD$suffix').absolute);
+    }
+
     _setIfChanged(_assetManifestJson, assetManifest);
     _setIfChanged(kFontManifestJson, fontManifest);
     _setIfChanged(_license, licenses);

packages/flutter_tools/test/general.shard/asset_bundle_test.dart

@@ -224,6 +224,83 @@ assets:
     ProcessManager: () => FakeProcessManager.any(),
   });
 
+  testUsingContext('inserts dummy file into additionalDependencies when '
+    'wildcards are used', () async {
+    globals.fs.file('.packages').createSync();
+    globals.fs.file(globals.fs.path.join('assets', 'bar.txt')).createSync(recursive: true);
+    globals.fs.file('pubspec.yaml')
+      ..createSync()
+      ..writeAsStringSync(r'''
+name: example
+flutter:
+  assets:
+    - assets/
+''');
+    final AssetBundle bundle = AssetBundleFactory.instance.createBundle();
+
+    expect(await bundle.build(manifestPath: 'pubspec.yaml'), 0);
+    expect(bundle.additionalDependencies.single.path, contains('DOES_NOT_EXIST_RERUN_FOR_WILDCARD'));
+  }, overrides: <Type, Generator>{
+    FileSystem: () => MemoryFileSystem.test(),
+    ProcessManager: () => FakeProcessManager.any(),
+  });
+
+  testUsingContext('Does not insert dummy file into additionalDependencies '
+    'when wildcards are not used', () async {
+    globals.fs.file('.packages').createSync();
+    globals.fs.file(globals.fs.path.join('assets', 'bar.txt')).createSync(recursive: true);
+    globals.fs.file('pubspec.yaml')
+      ..createSync()
+      ..writeAsStringSync(r'''
+name: example
+flutter:
+  assets:
+    - assets/bar.txt
+''');
+    final AssetBundle bundle = AssetBundleFactory.instance.createBundle();
+
+    expect(await bundle.build(manifestPath: 'pubspec.yaml'), 0);
+    expect(bundle.additionalDependencies, isEmpty);
+  }, overrides: <Type, Generator>{
+    FileSystem: () => MemoryFileSystem.test(),
+    ProcessManager: () => FakeProcessManager.any(),
+  });
+
+  testUsingContext('Does not insert dummy file into additionalDependencies '
+    'when wildcards are used by dependencies', () async {
+    globals.fs.file('.packages').writeAsStringSync(r'''
+example:lib/
+foo:foo/lib/
+''');
+    globals.fs.file(globals.fs.path.join('assets', 'foo', 'bar.txt'))
+      .createSync(recursive: true);
+    globals.fs.file('pubspec.yaml')
+      ..createSync()
+      ..writeAsStringSync(r'''
+name: example
+dependencies:
+  foo: any
+''');
+    globals.fs.file('foo/pubspec.yaml')
+      ..createSync(recursive: true)
+      ..writeAsStringSync(r'''
+name: foo
+
+flutter:
+  assets:
+    - bar/
+''');
+    final AssetBundle bundle = AssetBundleFactory.instance.createBundle();
+    globals.fs.file('foo/bar/fizz.txt').createSync(recursive: true);
+
+    expect(await bundle.build(manifestPath: 'pubspec.yaml'), 0);
+    expect(bundle.additionalDependencies, isEmpty);
+  }, overrides: <Type, Generator>{
+    FileSystem: () => MemoryFileSystem.test(),
+    ProcessManager: () => FakeProcessManager.any(),
+    Platform: () => FakePlatform(operatingSystem: 'linux'),
+  });
+
   testUsingContext('does not track wildcard directories from dependencies', () async {
     globals.fs.file('.packages').writeAsStringSync(r'''
 example:lib/