[camera_web] Add availableCameras implementation (flutter#4175)

packages/camera/camera_web/example/integration_test/camera_settings_test.dart

@@ -0,0 +1,210 @@
+// 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:html';
+
+import 'package:camera_platform_interface/camera_platform_interface.dart';
+import 'package:camera_web/src/camera_settings.dart';
+import 'package:camera_web/src/types/types.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:integration_test/integration_test.dart';
+import 'package:mocktail/mocktail.dart';
+
+import 'helpers/helpers.dart';
+
+void main() {
+  IntegrationTestWidgetsFlutterBinding.ensureInitialized();
+
+  group('CameraSettings', () {
+    late Window window;
+    late Navigator navigator;
+    late MediaDevices mediaDevices;
+    late CameraSettings settings;
+
+    setUp(() async {
+      window = MockWindow();
+      navigator = MockNavigator();
+      mediaDevices = MockMediaDevices();
+
+      when(() => window.navigator).thenReturn(navigator);
+      when(() => navigator.mediaDevices).thenReturn(mediaDevices);
+
+      settings = CameraSettings()..window = window;
+    });
+
+    group('getFacingModeForVideoTrack', () {
+      testWidgets(
+          'throws CameraException '
+          'with notSupported error '
+          'when there are no media devices', (tester) async {
+        when(() => navigator.mediaDevices).thenReturn(null);
+
+        expect(
+          () => settings.getFacingModeForVideoTrack(MockMediaStreamTrack()),
+          throwsA(
+            isA<CameraException>().having(
+              (e) => e.code,
+              'code',
+              CameraErrorCodes.notSupported,
+            ),
+          ),
+        );
+      });
+
+      testWidgets(
+          'returns null '
+          'when the facing mode is not supported', (tester) async {
+        when(mediaDevices.getSupportedConstraints).thenReturn({
+          'facingMode': false,
+        });
+
+        final facingMode =
+            settings.getFacingModeForVideoTrack(MockMediaStreamTrack());
+
+        expect(
+          facingMode,
+          equals(null),
+        );
+      });
+
+      group('when the facing mode is supported', () {
+        setUp(() {
+          when(mediaDevices.getSupportedConstraints).thenReturn({
+            'facingMode': true,
+          });
+        });
+
+        testWidgets(
+            'returns an appropriate facing mode '
+            'based on the video track settings', (tester) async {
+          final videoTrack = MockMediaStreamTrack();
+
+          when(videoTrack.getSettings).thenReturn({'facingMode': 'user'});
+
+          final facingMode = settings.getFacingModeForVideoTrack(videoTrack);
+
+          expect(
+            facingMode,
+            equals('user'),
+          );
+        });
+
+        testWidgets(
+            'returns an appropriate facing mode '
+            'based on the video track capabilities '
+            'when the facing mode setting is empty', (tester) async {
+          final videoTrack = MockMediaStreamTrack();
+
+          when(videoTrack.getSettings).thenReturn({});
+          when(videoTrack.getCapabilities).thenReturn({
+            'facingMode': ['environment', 'left']
+          });
+
+          final facingMode = settings.getFacingModeForVideoTrack(videoTrack);
+
+          expect(
+            facingMode,
+            equals('environment'),
+          );
+        });
+
+        testWidgets(
+            'returns null '
+            'when the facing mode setting '
+            'and capabilities are empty', (tester) async {
+          final videoTrack = MockMediaStreamTrack();
+
+          when(videoTrack.getSettings).thenReturn({});
+          when(videoTrack.getCapabilities).thenReturn({'facingMode': []});
+
+          final facingMode = settings.getFacingModeForVideoTrack(videoTrack);
+
+          expect(
+            facingMode,
+            equals(null),
+          );
+        });
+
+        testWidgets(
+            'returns null '
+            'when the facing mode setting is empty and '
+            'the video track capabilities are not supported', (tester) async {
+          final videoTrack = MockMediaStreamTrack();
+
+          when(videoTrack.getSettings).thenReturn({});
+          when(videoTrack.getCapabilities).thenThrow(JSNoSuchMethodError());
+
+          final facingMode = settings.getFacingModeForVideoTrack(videoTrack);
+
+          expect(
+            facingMode,
+            equals(null),
+          );
+        });
+
+        testWidgets(
+            'throws CameraException '
+            'with unknown error '
+            'when getting the video track capabilities '
+            'throws an unknown error', (tester) async {
+          final videoTrack = MockMediaStreamTrack();
+
+          when(videoTrack.getSettings).thenReturn({});
+          when(videoTrack.getCapabilities).thenThrow(Exception('Unknown'));
+
+          expect(
+            () => settings.getFacingModeForVideoTrack(videoTrack),
+            throwsA(
+              isA<CameraException>().having(
+                (e) => e.code,
+                'code',
+                CameraErrorCodes.unknown,
+              ),
+            ),
+          );
+        });
+      });
+    });
+
+    group('mapFacingModeToLensDirection', () {
+      testWidgets(
+          'returns front '
+          'when the facing mode is user', (tester) async {
+        expect(
+          settings.mapFacingModeToLensDirection('user'),
+          equals(CameraLensDirection.front),
+        );
+      });
+
+      testWidgets(
+          'returns back '
+          'when the facing mode is environment', (tester) async {
+        expect(
+          settings.mapFacingModeToLensDirection('environment'),
+          equals(CameraLensDirection.back),
+        );
+      });
+
+      testWidgets(
+          'returns external '
+          'when the facing mode is left', (tester) async {
+        expect(
+          settings.mapFacingModeToLensDirection('left'),
+          equals(CameraLensDirection.external),
+        );
+      });
+
+      testWidgets(
+          'returns external '
+          'when the facing mode is right', (tester) async {
+        expect(
+          settings.mapFacingModeToLensDirection('right'),
+          equals(CameraLensDirection.external),
+        );
+      });
+    });
+  });
+}
+
+class JSNoSuchMethodError implements Exception {}