Adds copy auth state API (#1018)

* Adds copy auth state API

* improvements

* Addresses comments

2 files changed, 148 insertions, 3 deletions

diff --git a/Example/Auth/Sample/MainViewController.m b/Example/Auth/Sample/MainViewController.m
index 18f1e02..e343508 100644
--- a/Example/Auth/Sample/MainViewController.m
+++ b/Example/Auth/Sample/MainViewController.m
@@ -429,6 +429,11 @@ static NSString *const kRemoveIDTokenListenerTitle = @"Remove Last ID Token Chan
  */
 static NSString *const kSectionTitleApp = @"APP";
 
+/** @var kUpdateCurrentUserFromSavedTitle
+    @brief The text of the "Upgrade to saved user" button.
+ */
+static NSString *const kUpdateCurrentUserFromSavedTitle = @"Upgrade to saved user";
+
 /** @var kCreateUserTitle
     @brief The text of the "Create User" button.
  */
@@ -745,6 +750,9 @@ typedef enum {
         }],
       ]],
       [StaticContentTableViewSection sectionWithTitle:kSectionTitleSignIn cells:@[
+        [StaticContentTableViewCell cellWithTitle:kUpdateCurrentUserFromSavedTitle
+                                            value:nil
+                                           action:^{ [weakSelf updateToSavedUser]; }],
         [StaticContentTableViewCell cellWithTitle:kCreateUserTitle
                                             value:nil
                                            action:^{ [weakSelf createUser]; }
@@ -2744,6 +2752,29 @@ static NSDictionary<NSString *, NSString *> *parseURL(NSString *urlString) {
   }];
 }
 
+/** @fn updateToSavedUser
+    @brief updates the current user to the saved user.
+ */
+- (void)updateToSavedUser {
+  if(![AppManager auth].currentUser) {
+    NSLog(@"You must be signed in to perform this action");
+    return;
+  }
+
+  if (!_userInMemory) {
+    NSLog(@"You need an in memory user to perform this action");
+    return;
+  }
+
+  [[AppManager auth] updateCurrentUser:_userInMemory completion:^(NSError *_Nullable error) {
+    if (error) {
+      [self showMessagePrompt:
+          [NSString stringWithFormat:@"An error Occurred: %@", error.localizedDescription]];
+      return;
+    }
+  }];
+}
+
 /** @fn createUser
     @brief Creates a new user.
  */
diff --git a/Example/Auth/Tests/FIRAuthTests.m b/Example/Auth/Tests/FIRAuthTests.m
index 914c58b..2e2d2c5 100644
--- a/Example/Auth/Tests/FIRAuthTests.m
+++ b/Example/Auth/Tests/FIRAuthTests.m
@@ -1773,6 +1773,111 @@ static const NSTimeInterval kWaitInterval = .5;
   return actionCodeSettings;
 }
 
+/** @fn testUpdateCurrentUserFailure
+    @brief Tests the flow of a failed @c updateCurrentUser:completion:
+        call.
+ */
+- (void)testUpdateCurrentUserFailure {
+  NSString *kTestAccessToken = @"fakeAccessToken";
+  NSString *kTestAPIKey = @"fakeAPIKey";
+  [self waitForSignInWithAccessToken:kTestAccessToken
+                              APIKey:kTestAPIKey
+                          completion:nil];
+    NSString *kTestAPIKey2 = @"fakeAPIKey2";
+    FIRUser *user2 = [FIRAuth auth].currentUser;
+    user2.requestConfiguration = [[FIRAuthRequestConfiguration alloc]initWithAPIKey:kTestAPIKey2];
+    OCMExpect([_mockBackend getAccountInfo:[OCMArg any] callback:[OCMArg any]])
+      .andDispatchError2([FIRAuthErrorUtils invalidAPIKeyError]);
+    XCTestExpectation *expectation = [self expectationWithDescription:@"callback"];
+    [[FIRAuth auth] updateCurrentUser:user2 completion:^(NSError *_Nullable error) {
+      XCTAssertEqual(error.code, FIRAuthErrorCodeInvalidAPIKey);
+      [expectation fulfill];
+    }];
+  [self waitForExpectationsWithTimeout:kExpectationTimeout handler:nil];
+  OCMVerifyAll(_mockBackend);
+}
+
+/** @fn testUpdateCurrentUserFailureNetworkError
+    @brief Tests the flow of a failed @c updateCurrentUser:completion:
+        call with a network error.
+ */
+- (void)testUpdateCurrentUserFailureNetworkError {
+  NSString *kTestAPIKey = @"fakeAPIKey";
+  NSString *kTestAccessToken = @"fakeAccessToken";
+  [self waitForSignInWithAccessToken:kTestAccessToken
+                              APIKey:kTestAPIKey
+                          completion:nil];
+    NSString *kTestAPIKey2 = @"fakeAPIKey2";
+    FIRUser *user2 = [FIRAuth auth].currentUser;
+    user2.requestConfiguration = [[FIRAuthRequestConfiguration alloc]initWithAPIKey:kTestAPIKey2];
+    OCMExpect([_mockBackend getAccountInfo:[OCMArg any] callback:[OCMArg any]])
+      .andDispatchError2([FIRAuthErrorUtils networkErrorWithUnderlyingError:[NSError new]]);
+    XCTestExpectation *expectation = [self expectationWithDescription:@"callback"];
+    [[FIRAuth auth] updateCurrentUser:user2 completion:^(NSError *_Nullable error) {
+      XCTAssertEqual(error.code, FIRAuthErrorCodeNetworkError);
+      [expectation fulfill];
+    }];
+  [self waitForExpectationsWithTimeout:kExpectationTimeout handler:nil];
+  OCMVerifyAll(_mockBackend);
+}
+
+/** @fn testUpdateCurrentUserFailureNUllUser
+    @brief Tests the flow of a failed @c updateCurrentUser:completion:
+        call with FIRAuthErrorCodeNullUser.
+ */
+- (void)testUpdateCurrentUserFailureNUllUser {
+  NSString *kTestAccessToken = @"fakeAccessToken";
+  NSString *kTestAPIKey = @"fakeAPIKey";
+  [self waitForSignInWithAccessToken:kTestAccessToken
+                              APIKey:kTestAPIKey
+                          completion:nil];
+    FIRUser *fakeNilUser = nil;
+    XCTestExpectation *expectation = [self expectationWithDescription:@"callback"];
+    [[FIRAuth auth] updateCurrentUser:fakeNilUser completion:^(NSError *_Nullable error) {
+      XCTAssertEqual(error.code, FIRAuthErrorCodeNullUser);
+      [expectation fulfill];
+    }];
+  [self waitForExpectationsWithTimeout:kExpectationTimeout handler:nil];
+  OCMVerifyAll(_mockBackend);
+}
+
+/** @fn testUpdateCurrentUserSuccess
+    @brief Tests the flow of a successful @c updateCurrentUser:completion:
+        call with a network error.
+ */
+- (void)testUpdateCurrentUserSuccess {
+  // Sign in with the first user.
+  [self waitForSignInWithAccessToken:kAccessToken
+                              APIKey:kAPIKey
+                          completion:nil];
+
+  FIRUser *user1 = [FIRAuth auth].currentUser;
+  NSString *kTestAPIKey = @"fakeAPIKey";
+  user1.requestConfiguration = [[FIRAuthRequestConfiguration alloc]initWithAPIKey:kTestAPIKey];
+  [[FIRAuth auth] signOut:nil];
+
+  NSString *kTestAccessToken2 = @"fakeAccessToken2";
+  [self waitForSignInWithAccessToken:kTestAccessToken2
+                              APIKey:kAPIKey
+                          completion:nil];
+  FIRUser *user2 = [FIRAuth auth].currentUser;
+
+  [self expectGetAccountInfoWithAccessToken:kAccessToken];
+
+  XCTestExpectation *expectation = [self expectationWithDescription:@"callback"];
+  // Current user should now be user2.
+  XCTAssertEqualObjects([FIRAuth auth].currentUser, user2);
+  [[FIRAuth auth] updateCurrentUser:user1 completion:^(NSError *_Nullable error) {
+    XCTAssertNil(error);
+    // Current user should now be user1.
+    XCTAssertEqualObjects([FIRAuth auth].currentUser, user1);
+    XCTAssertNotEqualObjects([FIRAuth auth].currentUser, user2);
+    [expectation fulfill];
+  }];
+  [self waitForExpectationsWithTimeout:kExpectationTimeout handler:nil];
+  OCMVerifyAll(_mockBackend);
+}
+
 /** @fn testSignOut
     @brief Tests the @c signOut: method.
  */
@@ -1884,7 +1989,7 @@ static const NSTimeInterval kWaitInterval = .5;
   // Listener should fire for signing in again as the same user with another access token.
   expectation = [self expectationWithDescription:@"sign-in again"];
   shouldHaveUser = YES;
-  [self waitForSignInWithAccessToken:kNewAccessToken];
+  [self waitForSignInWithAccessToken:kNewAccessToken APIKey:nil completion:nil];
 
   // Listener should fire for signing out.
   expectation = [self expectationWithDescription:@"sign-out"];
@@ -2256,15 +2361,19 @@ static const NSTimeInterval kWaitInterval = .5;
     @remarks This method also waits for all other pending @c XCTestExpectation instances.
  */
 - (void)waitForSignIn {
-  [self waitForSignInWithAccessToken:kAccessToken];
+  [self waitForSignInWithAccessToken:kAccessToken APIKey:nil completion:nil];
 }
 
 /** @fn waitForSignInWithAccessToken:
     @brief Signs in a user to prepare for tests.
     @param accessToken The access token for the user to have.
+    @param APIKey Optionally, The API key associated with the user.
+    @param completion Optionally, The completion invoked at the end of the flow.
     @remarks This method also waits for all other pending @c XCTestExpectation instances.
  */
-- (void)waitForSignInWithAccessToken:(NSString *)accessToken {
+- (void)waitForSignInWithAccessToken:(NSString *)accessToken
+                              APIKey:(nullable NSString *)APIKey
+                          completion:(nullable FIRAuthResultCallback)completion {
   OCMExpect([_mockBackend verifyPassword:[OCMArg any] callback:[OCMArg any]])
       .andCallBlock2(^(FIRVerifyPasswordRequest *_Nullable request,
                        FIRVerifyPasswordResponseCallback callback) {
@@ -2281,7 +2390,12 @@ static const NSTimeInterval kWaitInterval = .5;
   XCTestExpectation *expectation = [self expectationWithDescription:@"callback"];
   [[FIRAuth auth] signInWithEmail:kEmail password:kFakePassword completion:^(FIRUser *_Nullable user,
                                                                              NSError *_Nullable error) {
+
+    user.requestConfiguration = [[FIRAuthRequestConfiguration alloc] initWithAPIKey:APIKey];
     [expectation fulfill];
+    if (completion) {
+      completion(user, error);
+    }
   }];
   [self waitForExpectationsWithTimeout:kExpectationTimeout handler:nil];
   OCMVerifyAll(_mockBackend);