From c004904b196c54668c7066adb1b6f4d4c282ecaf Mon Sep 17 00:00:00 2001
From: Idan Entin <idane@dudamobile.com>
Date: Tue, 23 May 2017 23:51:43 +0300
Subject: [PATCH] feat(auth): Add ability to link user with email credentials
 to current user

---
 src/auth/FirebaseAuth.js        | 21 ++++++++
 tests/unit/FirebaseAuth.spec.js | 89 +++++++++++++++++++++++++++++++++
 2 files changed, 110 insertions(+)

diff --git a/src/auth/FirebaseAuth.js b/src/auth/FirebaseAuth.js
index 1b30251e..b2266118 100644
--- a/src/auth/FirebaseAuth.js
+++ b/src/auth/FirebaseAuth.js
@@ -59,6 +59,7 @@
         $updateEmail: this.updateEmail.bind(this),
         $deleteUser: this.deleteUser.bind(this),
         $sendPasswordResetEmail: this.sendPasswordResetEmail.bind(this),
+        $linkUser: this.linkUser.bind(this),
 
         // Hack: needed for tests
         _: this
@@ -334,6 +335,26 @@
       }
     },
 
+    /**
+     * Links the currently logged in user to a user with the given credentials.
+     *
+     * @param {string} email User's email
+     * @param {string} password User's password
+     * @return {Promise<firebase.User>} A promise fulfilled with the `firebase.User` object.
+     */
+    linkUser: function(email, password) {
+      var user = this.getAuth(),
+          credential;
+
+      if (!user) {
+        throw new Error('No user to link to (user must login before linking)');
+      }
+
+      credential = firebase.auth.EmailAuthProvider.credential(email, password);
+
+      return user.link(credential);
+    },
+
 
     /**
      * Sends a password reset email to an email/password user.
diff --git a/tests/unit/FirebaseAuth.spec.js b/tests/unit/FirebaseAuth.spec.js
index 4f524d32..5c4ded9f 100644
--- a/tests/unit/FirebaseAuth.spec.js
+++ b/tests/unit/FirebaseAuth.spec.js
@@ -681,4 +681,93 @@ describe('FirebaseAuth',function(){
       expect(result).toEqual('myResult');
     });
   });
+
+  describe('$linkUser()',function (){
+    it('should return a promise', function () {
+      var email = 'somebody@somewhere.com';
+      var password = 'myPass';
+      var credentials = {
+        provider: 'password',
+        uid: 'testUid',
+        link: jasmine.createSpy().and.returnValue(fakePromise())
+      };
+      spyOn(authService._, 'getAuth').and.returnValue(credentials);
+
+      expect(authService.$linkUser(email, password)).toBeAPromise();
+    });
+
+    it('should pass email and password to method on backing auth instance', function () {
+      var email = 'somebody@somewhere.com',
+          password = 'myPass';
+      var credentials = {
+        provider: 'password',
+        uid: 'testUid',
+        link: jasmine.createSpy().and.returnValue(fakePromise())
+      };
+      spyOn(authService._, 'getAuth').and.callFake(function () {
+        return credentials;
+      });
+
+      spyOn(firebase.auth.EmailAuthProvider, 'credential').and.returnValue(fakePromise());
+
+      authService.$linkUser(email, password);
+      expect(firebase.auth.EmailAuthProvider.credential).toHaveBeenCalledWith(email, password);
+    });
+
+    it('should call Firebase User\'s link method with email credentials', function () {
+      var email = 'somebody@somewhere.com',
+          password = 'myPass',
+          mockCredentials = 'mock credentials';
+      var fbUser = {
+        provider: 'password',
+        uid: 'testUid',
+        link: jasmine.createSpy()
+      };
+      spyOn(authService._, 'getAuth').and.callFake(function () {
+        return fbUser;
+      });
+
+      spyOn(firebase.auth.EmailAuthProvider, 'credential').and.returnValue(mockCredentials);
+
+      authService.$linkUser(email, password);
+
+      expect(fbUser.link).toHaveBeenCalledWith(mockCredentials);
+    });
+
+    it('should resolve promise with the user', function (done) {
+      var email = 'somebody@somewhere.com',
+          password = 'myPass',
+          mockCredentials = 'mock credentials';
+      var mockUser = {
+        provider: 'password',
+        uid: 'testUid',
+        link: jasmine.createSpy().and.callFake(function (aCredential) {
+          if (aCredential === mockCredentials) {
+            return Promise.resolve(mockUser);
+          }
+          return Promise.reject(new Error('Wrong mail / password'));
+        })
+      };
+      spyOn(authService._, 'getAuth').and.callFake(function () {
+        return mockUser;
+      });
+
+      spyOn(firebase.auth.EmailAuthProvider, 'credential').and.returnValue(mockCredentials);
+
+      authService.$linkUser(email, password)
+        .then(function (aUser) {
+          expect(aUser).toBe(mockUser);
+          done();
+        })
+        .catch(function (err) {
+          fail('failed due to an error in promise chain: ' + err.message);
+        });
+    });
+
+    it('should throw an error if there\'s no current user', function () {
+      spyOn(authService._, 'getAuth').and.returnValue(null);
+
+      expect(function () { authService.$linkUser('noone@nowhere.com', 'nevermind'); }).toThrow(new Error('No user to link to (user must login before linking)'));
+    });
+  });
 });