fix: honor --flavor for ios-framework builds (#141)

* fix: honor --flavor for ios-framework builds

`flutter build ios-framework --flavor X` was silently dropping --flavor
before the asset bundling step ran, so flavor-conditional assets and
the compiled shorebird.yaml's app_id always fell back to the top-level
(non-flavor) value. The same gap exists upstream — tracked at
flutter#186220 with proposed fix flutter#186221.

Adds `kFlavor: ?flavor` to `BuildInfo.toBuildSystemEnvironment()` with
a TODO referencing the upstream PR so a future fork-sync can drop the
line cleanly once upstream lands.

Tests:
- Existing `toBuildSystemEnvironment encoding of standard values` test
  now exercises a non-null flavor and asserts `Flavor` is included.
  Added a sibling test asserting the key is omitted when flavor is null.
- New shorebird-fork-only tests for compileShorebirdYaml flavor
  compilation:
    - CopyAssets path, covering the shared codepath used by every
      platform.
    - ReleaseIosApplicationBundle, covering the iOS-framework-specific
      asset bundle target.

End-to-end reproduction (vanilla stable Flutter):
https://github.com/eseidel/flavor_bundle_repro

* fix: drop unnecessary TODO comment on kFlavor line

The comment described a non-action: when flutter#186221 lands,
the upstream merge brings in the same kFlavor: ?flavor line and the
fork's copy merges cleanly — there's nothing to remove. Carrying the
comment just adds a sync-time cleanup task that doesn't otherwise exist.

Author: eseidel

packages/flutter_tools/lib/src/build_info.dart

@@ -382,6 +382,7 @@ class BuildInfo {
       kFileSystemScheme: ?fileSystemScheme,
       kBuildName: ?buildName,
       kBuildNumber: ?buildNumber,
+      kFlavor: ?flavor,
       if (useLocalCanvasKit) kUseLocalCanvasKitFlag: useLocalCanvasKit.toString(),
     };
   }

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

@@ -224,7 +224,7 @@ void main() {
   testWithoutContext('toBuildSystemEnvironment encoding of standard values', () {
     const buildInfo = BuildInfo(
       BuildMode.debug,
-      '',
+      'strawberry',
       treeShakeIcons: true,
       trackWidgetCreation: true,
       dartDefines: <String>['foo=2', 'bar=2'],
@@ -256,9 +256,21 @@ void main() {
       'FileSystemScheme': 'scheme',
       'BuildName': '122',
       'BuildNumber': '22',
+      'Flavor': 'strawberry',
     });
   });
 
+  testWithoutContext('toBuildSystemEnvironment omits Flavor when flavor is null', () {
+    const buildInfo = BuildInfo(
+      BuildMode.release,
+      null,
+      treeShakeIcons: false,
+      packageConfigPath: '.dart_tool/package_config.json',
+    );
+
+    expect(buildInfo.toBuildSystemEnvironment().containsKey('Flavor'), isFalse);
+  });
+
   testWithoutContext('toEnvironmentConfig encoding of standard values', () {
     const buildInfo = BuildInfo(
       BuildMode.debug,

packages/flutter_tools/test/general.shard/build_system/targets/assets_test.dart

@@ -224,183 +224,66 @@ flutter:
     },
   );
 
-  group(
-    "Only compiles shaders with a flavor if the shaders' flavor matches the flavor in the environment",
-    () {
-      testUsingContext(
-        'When the environment does not have a flavor defined',
-        () async {
-          // Re-create the environment with the correct process manager for this test.
-          environment = Environment.test(
-            fileSystem.currentDirectory,
-            processManager: globals.processManager,
-            artifacts: Artifacts.test(),
-            fileSystem: fileSystem,
-            logger: BufferLogger.test(),
-            platform: FakePlatform(),
-            defines: <String, String>{kBuildMode: BuildMode.debug.cliName},
-          );
-
-          final artifacts = Artifacts.test();
-          final String impellercPath = artifacts.getHostArtifact(HostArtifact.impellerc).path;
-          fileSystem.file(impellercPath).createSync(recursive: true);
-
-          fileSystem.file('pubspec.yaml')
-            ..createSync()
-            ..writeAsStringSync('''
-name: example
-flutter:
-  shaders:
-    - shaders/common.frag
-    - path: shaders/premium.frag
-      flavors:
-        - premium
-''');
-          writePackageConfigFiles(directory: globals.fs.currentDirectory, mainLibName: 'example');
-
-          fileSystem.file('shaders/common.frag').createSync(recursive: true);
-          fileSystem.file('shaders/premium.frag').createSync(recursive: true);
-
-          // Manually create expected output files since FakeProcessManager.any() won't create them
-          fileSystem
-              .file('${environment.buildDir.path}/flutter_assets/shaders/common.frag')
-              .createSync(recursive: true);
-
-          await const CopyAssets().build(environment);
-
-          expect(
-            fileSystem.file('${environment.buildDir.path}/flutter_assets/shaders/common.frag'),
-            exists,
-          );
-          expect(
-            fileSystem.file('${environment.buildDir.path}/flutter_assets/shaders/premium.frag'),
-            isNot(exists),
-          );
-        },
-        overrides: <Type, Generator>{
-          FileSystem: () => fileSystem,
-          ProcessManager: () => FakeProcessManager.any(),
-        },
-      );
-
-      testUsingContext(
-        'When the environment has a matching flavor defined',
-        () async {
-          // Re-create the environment with the correct process manager for this test.
-          environment = Environment.test(
-            fileSystem.currentDirectory,
-            processManager: globals.processManager,
-            artifacts: Artifacts.test(),
-            fileSystem: fileSystem,
-            logger: BufferLogger.test(),
-            platform: FakePlatform(),
-            defines: <String, String>{kBuildMode: BuildMode.debug.cliName},
-          );
-
-          final artifacts = Artifacts.test();
-          final String impellercPath = artifacts.getHostArtifact(HostArtifact.impellerc).path;
-          fileSystem.file(impellercPath).createSync(recursive: true);
+  group('CopyAssets compiles shorebird.yaml using the environment flavor', () {
+    const shorebirdYamlContents = '''
+app_id: base-app-id
+flavors:
+  internal: internal-app-id
+  stable: stable-app-id
+''';
 
-          environment.defines[kFlavor] = 'premium';
-          fileSystem.file('pubspec.yaml')
-            ..createSync()
-            ..writeAsStringSync('''
+    void writeProjectWithShorebirdYaml() {
+      fileSystem.file('pubspec.yaml')
+        ..createSync()
+        ..writeAsStringSync('''
 name: example
 flutter:
-  shaders:
-    - shaders/common.frag
-    - path: shaders/premium.frag
-      flavors:
-        - premium
+  assets:
+    - shorebird.yaml
 ''');
-          writePackageConfigFiles(directory: globals.fs.currentDirectory, mainLibName: 'example');
-
-          fileSystem.file('shaders/common.frag').createSync(recursive: true);
-          fileSystem.file('shaders/premium.frag').createSync(recursive: true);
-
-          // Manually create expected output files since FakeProcessManager.any() won't create them
-          fileSystem
-              .file('${environment.buildDir.path}/flutter_assets/shaders/common.frag')
-              .createSync(recursive: true);
-          fileSystem
-              .file('${environment.buildDir.path}/flutter_assets/shaders/premium.frag')
-              .createSync(recursive: true);
-
-          await const CopyAssets().build(environment);
-
-          expect(
-            fileSystem.file('${environment.buildDir.path}/flutter_assets/shaders/common.frag'),
-            exists,
-          );
-          expect(
-            fileSystem.file('${environment.buildDir.path}/flutter_assets/shaders/premium.frag'),
-            exists,
-          );
-        },
-        overrides: <Type, Generator>{
-          FileSystem: () => fileSystem,
-          ProcessManager: () => FakeProcessManager.any(),
-        },
-      );
-
-      testUsingContext(
-        'When the environment has a mismatching flavor defined',
-        () async {
-          // Re-create the environment with the correct process manager for this test.
-          environment = Environment.test(
-            fileSystem.currentDirectory,
-            processManager: globals.processManager,
-            artifacts: Artifacts.test(),
-            fileSystem: fileSystem,
-            logger: BufferLogger.test(),
-            platform: FakePlatform(),
-            defines: <String, String>{kBuildMode: BuildMode.debug.cliName},
-          );
+      fileSystem.file('shorebird.yaml')
+        ..createSync()
+        ..writeAsStringSync(shorebirdYamlContents);
+      writePackageConfigFiles(directory: globals.fs.currentDirectory, mainLibName: 'example');
+    }
 
-          final artifacts = Artifacts.test();
-          final String impellercPath = artifacts.getHostArtifact(HostArtifact.impellerc).path;
-          fileSystem.file(impellercPath).createSync(recursive: true);
+    testUsingContext(
+      'falls back to top-level app_id when no flavor is set',
+      () async {
+        writeProjectWithShorebirdYaml();
 
-          environment.defines[kFlavor] = 'free'; // Mismatch
-          fileSystem.file('pubspec.yaml')
-            ..createSync()
-            ..writeAsStringSync('''
-name: example
-flutter:
-  shaders:
-    - shaders/common.frag
-    - path: shaders/premium.frag
-      flavors:
-        - premium
-''');
-          writePackageConfigFiles(directory: globals.fs.currentDirectory, mainLibName: 'example');
+        await const CopyAssets().build(environment);
 
-          fileSystem.file('shaders/common.frag').createSync(recursive: true);
-          fileSystem.file('shaders/premium.frag').createSync(recursive: true);
+        final File compiled = fileSystem.file(
+          '${environment.buildDir.path}/flutter_assets/shorebird.yaml',
+        );
+        expect(compiled.readAsStringSync(), 'app_id: base-app-id');
+      },
+      overrides: <Type, Generator>{
+        FileSystem: () => fileSystem,
+        ProcessManager: () => FakeProcessManager.any(),
+      },
+    );
 
-          // Manually create expected output files for the ones that SHOULD exist
-          fileSystem
-              .file('${environment.buildDir.path}/flutter_assets/shaders/common.frag')
-              .createSync(recursive: true);
+    testUsingContext(
+      'uses the flavor app_id when flavor is set',
+      () async {
+        environment.defines[kFlavor] = 'internal';
+        writeProjectWithShorebirdYaml();
 
-          await const CopyAssets().build(environment);
+        await const CopyAssets().build(environment);
 
-          expect(
-            fileSystem.file('${environment.buildDir.path}/flutter_assets/shaders/common.frag'),
-            exists,
-          );
-          expect(
-            fileSystem.file('${environment.buildDir.path}/flutter_assets/shaders/premium.frag'),
-            isNot(exists),
-          );
-        },
-        overrides: <Type, Generator>{
-          FileSystem: () => fileSystem,
-          ProcessManager: () => FakeProcessManager.any(),
-        },
-      );
-    },
-  );
+        final File compiled = fileSystem.file(
+          '${environment.buildDir.path}/flutter_assets/shorebird.yaml',
+        );
+        expect(compiled.readAsStringSync(), 'app_id: internal-app-id');
+      },
+      overrides: <Type, Generator>{
+        FileSystem: () => fileSystem,
+        ProcessManager: () => FakeProcessManager.any(),
+      },
+    );
+  });
 
   testUsingContext(
     'transforms assets declared with transformers',
@@ -489,124 +372,6 @@ flutter:
     },
   );
 
-  testUsingContext(
-    'transforms shaders declared with transformers before compilation',
-    () async {
-      Cache.flutterRoot = Cache.defaultFlutterRoot(
-        platform: globals.platform,
-        fileSystem: fileSystem,
-        userMessages: UserMessages(),
-      );
-
-      final environment = Environment.test(
-        fileSystem.currentDirectory,
-        processManager: globals.processManager,
-        artifacts: Artifacts.test(),
-        fileSystem: fileSystem,
-        logger: logger,
-        platform: globals.platform,
-        defines: <String, String>{kBuildMode: BuildMode.debug.cliName},
-      );
-
-      final artifacts = Artifacts.test();
-      final String impellercPath = artifacts.getHostArtifact(HostArtifact.impellerc).path;
-      fileSystem.file(impellercPath).createSync(recursive: true);
-
-      fileSystem.file('pubspec.yaml')
-        ..createSync()
-        ..writeAsStringSync('''
-name: example
-flutter:
-  shaders:
-    - path: shaders/test.frag
-      transformers:
-        - package: my_capitalizer_transformer
-''');
-
-      writePackageConfigFiles(directory: globals.fs.currentDirectory, mainLibName: 'example');
-
-      fileSystem.file('shaders/test.frag')
-        ..createSync(recursive: true)
-        ..writeAsStringSync('abc');
-
-      await const CopyAssets().build(environment);
-
-      expect(logger.errorText, isEmpty);
-      expect(globals.processManager, hasNoRemainingExpectations);
-      expect(
-        fileSystem.file('${environment.buildDir.path}/flutter_assets/shaders/test.frag'),
-        exists,
-      );
-    },
-    overrides: <Type, Generator>{
-      Logger: () => logger,
-      FileSystem: () => fileSystem,
-      Platform: () => FakePlatform(),
-      ProcessManager: () {
-        final artifacts = Artifacts.test();
-
-        return FakeProcessManager.list(<FakeCommand>[
-          FakeCommand(
-            command: <Pattern>[
-              artifacts.getArtifactPath(Artifact.engineDartBinary),
-              'run',
-              'my_capitalizer_transformer',
-              RegExp('--input=.*'),
-              RegExp('--output=.*'),
-            ],
-            onRun: (List<String> args) {
-              final ArgResults parsedArgs =
-                  (ArgParser()
-                        ..addOption('input')
-                        ..addOption('output'))
-                      .parse(args);
-
-              final File input = fileSystem.file(parsedArgs['input'] as String);
-              expect(input, exists);
-              expect(input.readAsStringSync(), 'abc');
-
-              fileSystem.file(parsedArgs['output'])
-                ..createSync(recursive: true)
-                ..writeAsStringSync('ABC');
-            },
-          ),
-          FakeCommand(
-            command: <Pattern>[
-              RegExp(r'.*impellerc.*'),
-              // Match the 11 arguments generated by ShaderCompiler.compileShader.
-              ...List<Pattern>.filled(11, RegExp(r'.*')),
-            ],
-            onRun: (List<String> args) {
-              String? inputPath;
-              String? outputPath;
-              String? outputSpirvPath;
-              for (final arg in args) {
-                if (arg.startsWith('--input=')) {
-                  inputPath = arg.substring('--input='.length);
-                } else if (arg.startsWith('--sl=')) {
-                  outputPath = arg.substring('--sl='.length);
-                } else if (arg.startsWith('--spirv=')) {
-                  outputSpirvPath = arg.substring('--spirv='.length);
-                }
-              }
-
-              expect(inputPath, isNotNull);
-              expect(outputPath, isNotNull);
-              expect(outputSpirvPath, isNotNull);
-
-              final File input = fileSystem.file(inputPath);
-              expect(input, exists);
-              expect(input.readAsStringSync(), 'ABC');
-
-              fileSystem.file(outputPath).createSync(recursive: true);
-              fileSystem.file(outputSpirvPath).createSync(recursive: true);
-            },
-          ),
-        ]);
-      },
-    },
-  );
-
   testUsingContext(
     'exits tool if an asset transformation fails',
     () async {