[camerax] Marks all wrapped classes as immutable (#4451)

Marks all Dart-wrapped Android native classes as `@immutable`. They are all immutable anyway because they extend `JavaObject` which is immutable, but marking them as immutable explicitly avoids lint warnings caused by [`must_be_immutable`](https://dart.dev/tools/diagnostic-messages#must_be_immutable) when generated mocks of these classes are used (see dart-lang/mockito#200).

Also, updates `CONTRIBUTING.md` to include marking wrapped classes as immutable and extending `JavaObject` as requirements for adding new wrapped classes.

cc @ChristianEdwardPadilla: this should fix the internal lint errors caused by `JavaObject` being immutable.

packages/camera/camera_android_camerax/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.5.0+9
+
+* Marks all Dart-wrapped Android native classes as `@immutable`.
+* Updates `CONTRIBUTING.md` to note requirements of Dart-wrapped Android native classes.
+
 ## 0.5.0+8
 
 * Fixes unawaited_futures violations.

packages/camera/camera_android_camerax/CONTRIBUTING.md

@@ -48,7 +48,10 @@ an `InstanceManager` (implementation in `InstanceManager.java`).
 
 If CameraX or other Android classes that you need to access do not have a
 duplicately named implementation in `lib/src/`, then follow the same structure
-described above to add them.
+described above to add them. Please note that any Dart-wrapped native Android
+classes that you add should extend `JavaObject`. Additionally, they should be
+annotated as `@immutable` to avoid lint errors with mock objects that are
+generated for them that you may use for testing.
 
 For more information, please see the [design document][2] or feel free
 to ask any questions on the #hackers-ecosystem channel on [Discord][6]. For

packages/camera/camera_android_camerax/lib/src/analyzer.dart

@@ -5,7 +5,7 @@
 import 'dart:async';
 
 import 'package:flutter/services.dart' show BinaryMessenger;
-import 'package:meta/meta.dart' show protected;
+import 'package:meta/meta.dart' show immutable, protected;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -16,6 +16,7 @@ import 'java_object.dart';
 /// Wrapper of callback for analyzing images.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/ImageAnalysis.Analyzer.
+@immutable
 class Analyzer extends JavaObject {
   /// Creates an [Analyzer].
   Analyzer(

packages/camera/camera_android_camerax/lib/src/camera.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camera_info.dart';
@@ -14,6 +15,7 @@ import 'java_object.dart';
 /// camera, and publich the state of the camera.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/Camera.
+@immutable
 class Camera extends JavaObject {
   /// Constructs a [Camera] that is not automatically attached to a native object.
   Camera.detached(

packages/camera/camera_android_camerax/lib/src/camera_info.dart

@@ -5,6 +5,7 @@
 import 'dart:async';
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camera_state.dart';
@@ -18,6 +19,7 @@ import 'zoom_state.dart';
 /// The metadata of a camera.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/CameraInfo.
+@immutable
 class CameraInfo extends JavaObject {
   /// Constructs a [CameraInfo] that is not automatically attached to a native object.
   CameraInfo.detached(

packages/camera/camera_android_camerax/lib/src/camera_selector.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart';
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camera_info.dart';
@@ -13,6 +14,7 @@ import 'java_object.dart';
 /// Selects a camera for use.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/CameraSelector.
+@immutable
 class CameraSelector extends JavaObject {
   /// Creates a [CameraSelector].
   CameraSelector(

packages/camera/camera_android_camerax/lib/src/camera_state.dart

@@ -13,6 +13,7 @@ import 'java_object.dart';
 /// A snapshot of the camera state.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/CameraState.
+@immutable
 class CameraState extends JavaObject {
   /// Constructs a [CameraState] that is not automatically attached to a native object.
   CameraState.detached(

packages/camera/camera_android_camerax/lib/src/camera_state_error.dart

@@ -13,6 +13,7 @@ import 'java_object.dart';
 /// The error that a camera has encountered.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/CameraState.StateError.
+@immutable
 class CameraStateError extends JavaObject {
   /// Constructs a [CameraStateError] that is not automatically attached to a native object.
   CameraStateError.detached(

packages/camera/camera_android_camerax/lib/src/exposure_state.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -12,6 +13,7 @@ import 'java_object.dart';
 /// Represents exposure related information of a camera.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/ExposureState.
+@immutable
 class ExposureState extends JavaObject {
   /// Constructs a [ExposureState] that is not automatically attached to a native object.
   ExposureState.detached(

packages/camera/camera_android_camerax/lib/src/image_analysis.dart

@@ -5,6 +5,7 @@
 import 'dart:async';
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'analyzer.dart';
 import 'android_camera_camerax_flutter_api_impls.dart';
@@ -16,6 +17,7 @@ import 'use_case.dart';
 /// Use case for providing CPU accessible images for performing image analysis.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/ImageAnalysis.
+@immutable
 class ImageAnalysis extends UseCase {
   /// Creates an [ImageAnalysis].
   ImageAnalysis(

packages/camera/camera_android_camerax/lib/src/image_capture.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'camerax_library.g.dart';
 import 'instance_manager.dart';
@@ -12,6 +13,7 @@ import 'use_case.dart';
 /// Use case for picture taking.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/ImageCapture.
+@immutable
 class ImageCapture extends UseCase {
   /// Creates an [ImageCapture].
   ImageCapture({

packages/camera/camera_android_camerax/lib/src/image_proxy.dart

@@ -5,7 +5,7 @@
 import 'dart:async';
 
 import 'package:flutter/services.dart' show BinaryMessenger;
-import 'package:meta/meta.dart' show protected;
+import 'package:meta/meta.dart' show immutable, protected;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -16,6 +16,7 @@ import 'plane_proxy.dart';
 /// Representation of a single complete image buffer.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/ImageProxy.
+@immutable
 class ImageProxy extends JavaObject {
   /// Constructs a [ImageProxy] that is not automatically attached to a native object.
   ImageProxy.detached(

packages/camera/camera_android_camerax/lib/src/live_data.dart

@@ -18,6 +18,7 @@ import 'zoom_state.dart';
 /// Android Activity to which this plugin is attached.
 ///
 /// See https://developer.android.com/reference/androidx/lifecycle/LiveData.
+@immutable
 class LiveData<T extends Object> extends JavaObject {
   /// Constructs a [LiveData] that is not automatically attached to a native object.
   LiveData.detached({this.binaryMessenger, this.instanceManager})

packages/camera/camera_android_camerax/lib/src/observer.dart

@@ -14,6 +14,7 @@ import 'live_data.dart';
 /// Callback that can receive from [LiveData].
 ///
 /// See https://developer.android.com/reference/androidx/lifecycle/Observer.
+@immutable
 class Observer<T> extends JavaObject {
   /// Constructor for [Observer].
   Observer(

packages/camera/camera_android_camerax/lib/src/pending_recording.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -13,6 +14,7 @@ import 'recording.dart';
 /// Dart wrapping of PendingRecording CameraX class.
 ///
 /// See https://developer.android.com/reference/androidx/camera/video/PendingRecording
+@immutable
 class PendingRecording extends JavaObject {
   /// Creates a [PendingRecording] that is not automatically attached to
   /// a native object.

packages/camera/camera_android_camerax/lib/src/plane_proxy.dart

@@ -5,7 +5,7 @@
 import 'dart:typed_data';
 
 import 'package:flutter/services.dart' show BinaryMessenger;
-import 'package:meta/meta.dart' show protected;
+import 'package:meta/meta.dart' show immutable, protected;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -15,6 +15,7 @@ import 'java_object.dart';
 /// A single color plane of image data.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/ImageProxy.PlaneProxy.
+@immutable
 class PlaneProxy extends JavaObject {
   /// Constructs a [PlaneProxy] that is not automatically attached to a native object.
   PlaneProxy.detached(

packages/camera/camera_android_camerax/lib/src/preview.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'camerax_library.g.dart';
 import 'instance_manager.dart';
@@ -12,6 +13,7 @@ import 'use_case.dart';
 /// Use case that provides a camera preview stream for display.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/Preview.
+@immutable
 class Preview extends UseCase {
   /// Creates a [Preview].
   Preview(

packages/camera/camera_android_camerax/lib/src/process_camera_provider.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart';
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camera.dart';
@@ -16,6 +17,7 @@ import 'use_case.dart';
 /// Provides an object to manage the camera.
 ///
 /// See https://developer.android.com/reference/androidx/camera/lifecycle/ProcessCameraProvider.
+@immutable
 class ProcessCameraProvider extends JavaObject {
   /// Creates a detached [ProcessCameraProvider].
   ProcessCameraProvider.detached(

packages/camera/camera_android_camerax/lib/src/recorder.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart';
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -13,6 +14,7 @@ import 'pending_recording.dart';
 /// A dart wrapping of the CameraX Recorder class.
 ///
 /// See https://developer.android.com/reference/androidx/camera/video/Recorder.
+@immutable
 class Recorder extends JavaObject {
   /// Creates a [Recorder].
   Recorder(

packages/camera/camera_android_camerax/lib/src/recording.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -12,6 +13,7 @@ import 'java_object.dart';
 /// Wraps a CameraX recording class.
 ///
 /// See https://developer.android.com/reference/androidx/camera/video/Recording.
+@immutable
 class Recording extends JavaObject {
   /// Constructs a detached [Recording]
   Recording.detached(

packages/camera/camera_android_camerax/lib/src/surface.dart

@@ -2,11 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:meta/meta.dart' show immutable;
+
 import 'java_object.dart';
 
 /// Handle onto the raw buffer managed by screen compositor.
 ///
 /// See https://developer.android.com/reference/android/view/Surface.html.
+@immutable
 class Surface extends JavaObject {
   /// Creates a detached [Surface].
   Surface.detached({super.binaryMessenger, super.instanceManager})

packages/camera/camera_android_camerax/lib/src/use_case.dart

@@ -2,11 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:meta/meta.dart' show immutable;
+
 import 'java_object.dart';
 
 /// An object representing the different functionalities of the camera.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/UseCase.
+@immutable
 class UseCase extends JavaObject {
   /// Creates a detached [UseCase].
   UseCase.detached({super.binaryMessenger, super.instanceManager})

packages/camera/camera_android_camerax/lib/src/video_capture.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart';
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -14,6 +15,7 @@ import 'use_case.dart';
 /// Dart wrapping of CameraX VideoCapture class.
 ///
 /// See https://developer.android.com/reference/androidx/camera/video/VideoCapture.
+@immutable
 class VideoCapture extends UseCase {
   /// Creates a VideoCapture that is not automatically attached to a native object.
   VideoCapture.detached(

packages/camera/camera_android_camerax/lib/src/zoom_state.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart' show BinaryMessenger;
+import 'package:meta/meta.dart' show immutable;
 
 import 'android_camera_camerax_flutter_api_impls.dart';
 import 'camerax_library.g.dart';
@@ -12,6 +13,7 @@ import 'java_object.dart';
 /// Represents zoom related information of a camera.
 ///
 /// See https://developer.android.com/reference/androidx/camera/core/ZoomState.
+@immutable
 class ZoomState extends JavaObject {
   /// Constructs a [CameraInfo] that is not automatically attached to a native object.
   ZoomState.detached(

packages/camera/camera_android_camerax/pubspec.yaml

@@ -2,7 +2,7 @@ name: camera_android_camerax
 description: Android implementation of the camera plugin using the CameraX library.
 repository: https://github.com/flutter/packages/tree/main/packages/camera/camera_android_camerax
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+camera%22
-version: 0.5.0+8
+version: 0.5.0+9
 
 environment:
   sdk: ">=2.19.0 <4.0.0"

packages/camera/camera_android_camerax/test/analyzer_test.mocks.dart

@@ -1,7 +1,9 @@
-// Mocks generated by Mockito 5.4.0 from annotations
+// Mocks generated by Mockito 5.4.1 from annotations
 // in camera_android_camerax/test/analyzer_test.dart.
 // Do not manually edit this file.
 
+// @dart=2.19
+
 // ignore_for_file: no_leading_underscores_for_library_prefixes
 import 'package:mockito/mockito.dart' as _i1;