[url_launcher] Add overridable platform

packages/url_launcher/url_launcher/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 5.2.3
+
+* Adds `urlLauncherPlatform` which can be overridden to implement `url_launcher`
+  on other platforms (which may not want to use MethodChannels).
+
 ## 5.2.2
 
 * Re-land embedder v2 support with correct Flutter SDK constraints.

packages/url_launcher/url_launcher/lib/method_channel_url_launcher.dart

@@ -0,0 +1,47 @@
+import 'dart:async';
+
+import 'package:flutter/services.dart';
+
+import 'url_launcher_platform_interface.dart';
+
+const MethodChannel _channel = MethodChannel('plugins.flutter.io/url_launcher');
+
+/// An implementation of [UrlLauncherPlatform] that uses method channels.
+class MethodChannelUrlLauncher extends UrlLauncherPlatform {
+  @override
+  Future<bool> canLaunch(String url) {
+    return _channel.invokeMethod<bool>(
+      'canLaunch',
+      <String, Object>{'url': url},
+    );
+  }
+
+  @override
+  Future<void> closeWebView() {
+    return _channel.invokeMethod<void>('closeWebView');
+  }
+
+  @override
+  Future<bool> launch(
+    String url,
+    bool useSafariVC,
+    bool useWebView,
+    bool enableJavaScript,
+    bool enableDomStorage,
+    bool universalLinksOnly,
+    Map<String, String> headers,
+  ) {
+    _channel.invokeMethod<bool>(
+      'launch',
+      <String, Object>{
+        'url': url,
+        'useSafariVC': useSafariVC,
+        'useWebView': useWebView,
+        'enableJavaScript': enableJavaScript,
+        'enableDomStorage': enableDomStorage,
+        'universalLinksOnly': universalLinksOnly,
+        'headers': headers,
+      },
+    );
+  }
+}

packages/url_launcher/url_launcher/lib/url_launcher.dart

@@ -8,7 +8,8 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 
-const MethodChannel _channel = MethodChannel('plugins.flutter.io/url_launcher');
+import 'url_launcher_platform_interface.dart';
+import 'method_channel_url_launcher.dart';
 
 /// Parses the specified URL string and delegates handling of it to the
 /// underlying platform.
@@ -84,17 +85,14 @@ Future<bool> launch(
         ? SystemUiOverlayStyle.dark
         : SystemUiOverlayStyle.light);
   }
-  final bool result = await _channel.invokeMethod<bool>(
-    'launch',
-    <String, Object>{
-      'url': urlString,
-      'useSafariVC': forceSafariVC ?? isWebURL,
-      'useWebView': forceWebView ?? false,
-      'enableJavaScript': enableJavaScript ?? false,
-      'enableDomStorage': enableDomStorage ?? false,
-      'universalLinksOnly': universalLinksOnly ?? false,
-      'headers': headers ?? <String, String>{},
-    },
+  final bool result = await urlLauncherPlatform.launch(
+    urlString,
+    forceSafariVC ?? isWebURL,
+    forceWebView ?? false,
+    enableJavaScript ?? false,
+    enableDomStorage ?? false,
+    universalLinksOnly ?? false,
+    headers ?? <String, String>{},
   );
   if (statusBarBrightness != null) {
     WidgetsBinding.instance.renderView.automaticSystemUiAdjustment =
@@ -109,10 +107,7 @@ Future<bool> canLaunch(String urlString) async {
   if (urlString == null) {
     return false;
   }
-  return await _channel.invokeMethod<bool>(
-    'canLaunch',
-    <String, Object>{'url': urlString},
-  );
+  return await urlLauncherPlatform.canLaunch(urlString);
 }
 
 /// Closes the current WebView, if one was previously opened via a call to [launch].
@@ -127,5 +122,25 @@ Future<bool> canLaunch(String urlString) async {
 /// SafariViewController is only available on IOS version >= 9.0, this method does not do anything
 /// on IOS version below 9.0
 Future<void> closeWebView() async {
-  return await _channel.invokeMethod<void>('closeWebView');
+  return await urlLauncherPlatform.closeWebView();
+}
+
+UrlLauncherPlatform _platform;
+
+/// The [UrlLauncherPlatform] that will do the platform-specific work.
+///
+/// Defaults to [MethodChannelUrlLauncher].
+UrlLauncherPlatform get urlLauncherPlatform {
+  if (_platform == null) {
+    _platform = MethodChannelUrlLauncher();
+  }
+  return _platform;
+}
+
+/// Sets the [UrlLauncherPlatform] to use.
+///
+/// Set the platform if you have a platform-specific implementation of
+/// [UrlLauncherPlatform] that you would like to use.
+set urlLauncherPlatform(UrlLauncherPlatform newPlatform) {
+  _platform = newPlatform;
 }

packages/url_launcher/url_launcher/lib/url_launcher_platform_interface.dart

@@ -0,0 +1,29 @@
+// Copyright 2017 The Chromium 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:async';
+
+/// The interface that implementations of url_launcher must implement.
+abstract class UrlLauncherPlatform {
+  /// Returns `true` if this platform is able to launch [url].
+  Future<bool> canLaunch(String url);
+
+  /// Returns `true` if the given [url] was successfully launched.
+  ///
+  /// For documentation on the other arguments, see the `launch` documentation
+  /// in `package:url_launcher/url_launcher.dart`.
+  Future<bool> launch(
+      String url,
+      bool useSafariVC,
+      bool useWebView,
+      bool enableJavaScript,
+      bool enableDomStorage,
+      bool universalLinksOnly,
+      Map<String, String> headers,
+  );
+
+
+  /// Closes the WebView, if one was opened earlier by `launch`.
+  Future<void> closeWebView();
+}

packages/url_launcher/url_launcher/pubspec.yaml

@@ -3,7 +3,7 @@ description: Flutter plugin for launching a URL on Android and iOS. Supports
   web, phone, SMS, and email schemes.
 author: Flutter Team <[email protected]>
 homepage: https://github.com/flutter/plugins/tree/master/packages/url_launcher/url_launcher
-version: 5.2.2
+version: 5.2.3
 
 flutter:
   plugin:

packages/url_launcher/url_launcher/test/url_launcher_platform_test.dart

@@ -0,0 +1,67 @@
+// Copyright 2017 The Chromium 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 'package:flutter_test/flutter_test.dart';
+import 'package:url_launcher/url_launcher.dart';
+import 'package:url_launcher/url_launcher_platform_interface.dart';
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  group('UrlLauncher with mock platform', () {
+    final MockUrlLauncherPlatform platform = MockUrlLauncherPlatform();
+    urlLauncherPlatform = platform;
+
+    test('can mock "canLaunch"', () async {
+      expect(canLaunch('http://www.google.com'), completion(isFalse));
+
+      platform.launchableUrls.add('http://www.google.com');
+
+      expect(canLaunch('http://www.google.com'), completion(isTrue));
+
+      platform.launchableUrls.clear();
+    });
+
+    test('can mock "launch"', () async {
+      expect(launch('http://www.google.com'), completion(isFalse));
+
+      platform.launchableUrls.add('http://www.google.com');
+
+      expect(launch('http://www.google.com'), completion(isTrue));
+
+      platform.launchableUrls.clear();
+    });
+
+    test('can mock "closeWebView"', () async {
+      expect(closeWebView(), completes);
+    });
+  });
+}
+
+class MockUrlLauncherPlatform extends UrlLauncherPlatform {
+  Set<String> launchableUrls = Set<String>();
+
+  @override
+  Future<bool> canLaunch(String url) {
+    return Future.value(launchableUrls.contains(url));
+  }
+
+  @override
+  Future<void> closeWebView() {
+    return Future<void>.value();
+  }
+
+  @override
+  Future<bool> launch(
+    String url,
+    bool useSafariVC,
+    bool useWebView,
+    bool enableJavaScript,
+    bool enableDomStorage,
+    bool universalLinksOnly,
+    Map<String, String> headers,
+  ) {
+    return Future.value(launchableUrls.contains(url));
+  }
+}