Adding support for FirebaseUser.unlink(providerId)

packages/firebase_auth/android/src/main/java/io/flutter/plugins/firebaseauth/FirebaseAuthPlugin.java

@@ -111,6 +111,9 @@ public void onMethodCall(MethodCall call, Result result) {
       case "linkWithFacebookCredential":
         handleLinkWithFacebookCredential(call, result);
         break;
+      case "unlink":
+        handleUnlink(call, result);
+        break;
       case "updateProfile":
         handleUpdateProfile(call, result);
         break;
@@ -372,6 +375,16 @@ private void handleLinkWithFacebookCredential(MethodCall call, final Result resu
         .addOnCompleteListener(new SignInCompleteListener(result));
   }
 
+  private void handleUnlink(MethodCall call, final Result result) {
+    @SuppressWarnings("unchecked")
+    Map<String, String> arguments = (Map<String, String>) call.arguments;
+    String providerId = arguments.get("providerId");
+    firebaseAuth
+        .getCurrentUser()
+        .unlink(providerId)
+        .addOnCompleteListener(new SignInCompleteListener(result));
+  }
+
   private void handleSignInWithFacebook(MethodCall call, final Result result) {
     @SuppressWarnings("unchecked")
     Map<String, String> arguments = (Map<String, String>) call.arguments;

packages/firebase_auth/ios/Classes/FirebaseAuthPlugin.m

@@ -176,6 +176,12 @@ - (void)handleMethodCall:(FlutterMethodCall *)call result:(FlutterResult)result
                                         completion:^(FIRUser *user, NSError *error) {
                                           [self sendResult:result forUser:user error:error];
                                         }];
+  } else if ([@"unlink" isEqualToString:call.method]) {
+    NSString *providerId = call.arguments[@"providerId"];
+    [[FIRAuth auth].currentUser unlinkFromProvider:providerId
+                                        completion:^(FIRUser *user, NSError *error) {
+                                          [self sendResult:result forUser:user error:error];
+                                        }];
   } else if ([@"updateProfile" isEqualToString:call.method]) {
     FIRUserProfileChangeRequest *changeRequest = [[FIRAuth auth].currentUser profileChangeRequest];
     if (call.arguments[@"displayName"]) {

packages/firebase_auth/lib/firebase_auth.dart

@@ -428,6 +428,19 @@ class FirebaseAuth {
     return currentUser;
   }
 
+  Future<FirebaseUser> unlink({
+    @required String providerId,
+  }) async {
+    final Map<dynamic, dynamic> data = await channel.invokeMethod(
+      'unlink',
+      <String, String>{
+        'providerId': providerId,
+      },
+    );
+    final FirebaseUser currentUser = new FirebaseUser._(data);
+    return currentUser;
+  }
+
   /// Sets the user-facing language code for auth operations that can be
   /// internationalized, such as [sendEmailVerification]. This language
   /// code should follow the conventions defined by the IETF in BCP47.

packages/firebase_auth/test/firebase_auth_test.dart

@@ -247,6 +247,24 @@ void main() {
       );
     });
 
+    test('unlink', () async {
+      final FirebaseUser user = await auth.unlink(
+        providerId: kMockProviderId,
+      );
+      verifyUser(user);
+      expect(
+        log,
+        <Matcher>[
+          isMethodCall(
+            'unlink',
+            arguments: <String, String>{
+              'providerId': kMockProviderId,
+            },
+          ),
+        ],
+      );
+    });
+
     test('signInWithFacebook', () async {
       final FirebaseUser user = await auth.signInWithFacebook(
         accessToken: kMockAccessToken,
@@ -378,7 +396,7 @@ void main() {
 
     test('updateEmail', () async {
       final String updatedEmail = 'atestemail@gmail.com';
-      auth.updateEmail(email: updatedEmail);
+      await auth.updateEmail(email: updatedEmail);
       expect(
         log,
         <Matcher>[