[camera_android_camerax] Removes internal native library Dart proxy (#10536)

ProxyApis now
* Generate a Dart `PigeonOverrides` class that can override constructors and static methods.
* Use a test `PigeonInstanceManager` that doesn't make any message calls.

This removes the manually written proxy and replaces its use in tests with `PigeonOverrides`. 

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Author: bparrishMines

packages/camera/camera_android_camerax/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.6.26
+
+* Removes internal native library Dart proxy.
+
 ## 0.6.25+1
 
 * Bumps kotlin_version to 2.2.21.

packages/camera/camera_android_camerax/android/src/main/java/io/flutter/plugins/camerax/CameraXLibrary.g.kt

@@ -1,7 +1,7 @@
 // Copyright 2013 The Flutter Authors
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
-// Autogenerated from Pigeon (v26.1.0), do not edit directly.
+// Autogenerated from Pigeon (v26.1.2), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 @file:Suppress("UNCHECKED_CAST", "ArrayInDataClass")
 
@@ -213,7 +213,7 @@ class CameraXLibraryPigeonInstanceManager(
   }
 
   /** Retrieves the instance associated with identifier, if present, otherwise `null`. */
-  fun <T> getInstance(identifier: Long): T? {
+  fun <T : Any> getInstance(identifier: Long): T? {
     logWarningIfFinalizationListenerHasStopped()
     val instance = weakInstances[identifier] as IdentityWeakReference<T>?
     return instance?.get()

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

@@ -9,28 +9,46 @@ import 'camerax_library.g.dart' as camerax;
 
 export 'camerax_library.g.dart' hide CameraInfo, LiveData, Observer;
 
+/// Provides overrides for the constructors and static members of classes that
+/// extend Dart proxy classes.
+///
+/// Intended to be similar to [camerax.PigeonOverrides].
+///
+/// This is only intended to be used with unit tests to prevent errors from
+/// making message calls in a unit test.
+///
+/// See [GenericsPigeonOverrides.reset] to set all overrides back to null.
+@visibleForTesting
+final class GenericsPigeonOverrides {
+  /// Overrides [Observer.new].
+  static Observer<T> Function<T>({
+    required void Function(Observer<T> pigeonInstance, T value) onChanged,
+  })?
+  observerNew;
+
+  /// Sets all overridden ProxyApi class members to null.
+  static void reset() {
+    observerNew = null;
+  }
+}
+
 /// Handles adding support for generics to the API wrapper.
 ///
 /// APIs wrapped with the pigeon ProxyAPI system doesn't support generics, so
 /// this handles using subclasses to add support.
-void setUpGenerics({
-  BinaryMessenger? pigeonBinaryMessenger,
-  camerax.PigeonInstanceManager? pigeonInstanceManager,
-}) {
+void setUpGenerics({BinaryMessenger? pigeonBinaryMessenger}) {
   camerax.LiveData.pigeon_setUpMessageHandlers(
     pigeon_newInstance: (camerax.LiveDataSupportedType type) {
       switch (type) {
         case camerax.LiveDataSupportedType.cameraState:
           return LiveData<camerax.CameraState>.detached(
             type: type,
             pigeon_binaryMessenger: pigeonBinaryMessenger,
-            pigeon_instanceManager: pigeonInstanceManager,
           );
         case camerax.LiveDataSupportedType.zoomState:
           return LiveData<camerax.ZoomState>.detached(
             type: type,
             pigeon_binaryMessenger: pigeonBinaryMessenger,
-            pigeon_instanceManager: pigeonInstanceManager,
           );
       }
     },
@@ -43,7 +61,6 @@ void setUpGenerics({
             sensorRotationDegrees: sensorRotationDegrees,
             exposureState: exposureState,
             pigeon_binaryMessenger: pigeonBinaryMessenger,
-            pigeon_instanceManager: pigeonInstanceManager,
           );
         },
   );
@@ -87,8 +104,6 @@ class CameraInfo extends camerax.CameraInfo {
     required super.exposureState,
     // ignore: non_constant_identifier_names
     super.pigeon_binaryMessenger,
-    // ignore: non_constant_identifier_names
-    super.pigeon_instanceManager,
   }) : super.pigeon_detached();
 
   @override
@@ -108,7 +123,6 @@ class CameraInfo extends camerax.CameraInfo {
       sensorRotationDegrees: sensorRotationDegrees,
       exposureState: exposureState,
       pigeon_binaryMessenger: pigeon_binaryMessenger,
-      pigeon_instanceManager: pigeon_instanceManager,
     );
   }
 }
@@ -130,8 +144,6 @@ class LiveData<T> extends camerax.LiveData {
     required super.type,
     // ignore: non_constant_identifier_names
     super.pigeon_binaryMessenger,
-    // ignore: non_constant_identifier_names
-    super.pigeon_instanceManager,
   }) : super.pigeon_detached();
 
   @override
@@ -150,7 +162,6 @@ class LiveData<T> extends camerax.LiveData {
     return LiveData<T>.detached(
       type: type,
       pigeon_binaryMessenger: pigeon_binaryMessenger,
-      pigeon_instanceManager: pigeon_instanceManager,
     );
   }
 }
@@ -160,12 +171,25 @@ class LiveData<T> extends camerax.LiveData {
 /// See https://developer.android.com/reference/androidx/lifecycle/Observer.
 class Observer<T> extends camerax.Observer {
   /// Constructs an [Observer].
-  Observer({
+  factory Observer({
+    required void Function(Observer<T> instance, T value) onChanged,
+    BinaryMessenger? binaryMessenger,
+  }) {
+    if (GenericsPigeonOverrides.observerNew != null) {
+      return GenericsPigeonOverrides.observerNew!(onChanged: onChanged);
+    }
+    return Observer<T>.pigeonNew(
+      pigeon_binaryMessenger: binaryMessenger,
+      onChanged: onChanged,
+    );
+  }
+
+  /// Constructs an [Observer].
+  @protected
+  Observer.pigeonNew({
     required void Function(Observer<T> instance, T value) onChanged,
     // ignore: non_constant_identifier_names
     super.pigeon_binaryMessenger,
-    // ignore: non_constant_identifier_names
-    super.pigeon_instanceManager,
   }) : _genericOnChanged = onChanged,
        super.pigeon_new(
          onChanged: (camerax.Observer instance, Object value) {
@@ -181,8 +205,6 @@ class Observer<T> extends camerax.Observer {
     required void Function(Observer<T> instance, T value) onChanged,
     // ignore: non_constant_identifier_names
     super.pigeon_binaryMessenger,
-    // ignore: non_constant_identifier_names
-    super.pigeon_instanceManager,
   }) : _genericOnChanged = onChanged,
        super.pigeon_detached(
          onChanged: (camerax.Observer instance, Object value) {
@@ -198,7 +220,6 @@ class Observer<T> extends camerax.Observer {
     return Observer<T>.detached(
       onChanged: _genericOnChanged,
       pigeon_binaryMessenger: pigeon_binaryMessenger,
-      pigeon_instanceManager: pigeon_instanceManager,
     );
   }
 }

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

@@ -1,7 +1,7 @@
 // Copyright 2013 The Flutter Authors
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
-// Autogenerated from Pigeon (v26.1.0), do not edit directly.
+// Autogenerated from Pigeon (v26.1.2), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 // ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import, unnecessary_parenthesis, prefer_null_aware_operators, omit_local_variable_types, unused_shown_name, unnecessary_import, no_leading_underscores_for_local_identifiers