[android][auth] implemented missing 'unlink' method

android/src/main/java/io/invertase/firebase/auth/RNFirebaseAuth.java

@@ -643,6 +643,38 @@ public class RNFirebaseAuth extends ReactContextBaseJavaModule {
     }
   }
 
+  /**
+   * unlink
+   *
+   * @url https://firebase.google.com/docs/reference/android/com/google/firebase/auth/FirebaseUser.html#unlink(java.lang.String)
+   * @param providerId
+   * @param promise
+   */
+  @ReactMethod
+  public void unlink(final String providerId, final Promise promise) {
+    FirebaseUser user = mAuth.getCurrentUser();
+    Log.d(TAG, "unlink");
+
+    if (user != null) {
+      user.unlink(providerId)
+        .addOnCompleteListener(new OnCompleteListener<AuthResult>() {
+          @Override
+          public void onComplete(@NonNull Task<AuthResult> task) {
+            if (task.isSuccessful()) {
+              Log.d(TAG, "unlink:onComplete:success");
+              promiseWithUser(task.getResult().getUser(), promise);
+            } else {
+              Exception exception = task.getException();
+              Log.e(TAG, "unlink:onComplete:failure", exception);
+              promiseRejectAuthException(promise, exception);
+            }
+          }
+        });
+    } else {
+      promiseNoUser(promise, true);
+    }
+  }
+
   /**
    * reauthenticate
    *

ios/RNFirebase/auth/RNFirebaseAuth.m

@@ -478,6 +478,32 @@ RCT_EXPORT_METHOD(link:(NSString *)provider authToken:(NSString *)authToken auth
     }
 }
 
+/**
+ unlink
+
+ @param NSString provider
+ @param NSString authToken
+ @param NSString authSecret
+ @param RCTPromiseResolveBlock resolve
+ @param RCTPromiseRejectBlock reject
+ @return
+ */
+RCT_EXPORT_METHOD(unlink:(NSString *)providerId resolver:(RCTPromiseResolveBlock) resolve rejecter:(RCTPromiseRejectBlock) reject) {
+    FIRUser *user = [FIRAuth auth].currentUser;
+
+    if (user) {
+        [user unlinkFromProvider:providerId completion:^(FIRUser *_Nullable _user, NSError *_Nullable error) {
+            if (error) {
+                [self promiseRejectAuthException:reject error:error];
+            } else {
+                [self promiseWithUser:resolve rejecter:reject user:_user];
+            }
+        }];
+    } else {
+        [self promiseNoUser:resolve rejecter:reject isError:YES];
+    }
+}
+
 /**
  reauthenticate
 

lib/modules/auth/user.js

@@ -64,11 +64,11 @@ export default class User {
    * PROPERTIES
    */
 
-  get displayName(): String|null {
+  get displayName(): String | null {
     return this._valueOrNull('displayName');
   }
 
-  get email(): String|null {
+  get email(): String | null {
     return this._valueOrNull('email');
   }
 
@@ -80,7 +80,7 @@ export default class User {
     return this._valueOrFalse('isAnonymous');
   }
 
-  get photoURL(): String|null {
+  get photoURL(): String | null {
     return this._valueOrNull('photoURL');
   }
 
@@ -117,6 +117,15 @@ export default class User {
     return this._auth._interceptUserValue(FirebaseAuth.link(credential.provider, credential.token, credential.secret));
   }
 
+  /**
+   *
+   * @param providerId
+   * @return {Promise.<TResult>|*}
+   */
+  unlink(providerId: string) {
+    return this._auth._interceptUserValue(FirebaseAuth.unlink(providerId));
+  }
+
   /**
    * Re-authenticate a user with a third-party authentication provider
    * @return {Promise}         A promise resolved upon completion