[ObjC ARC] Converts ios/chrome/browser/ui/authentication:authentication to ARC.

ios/chrome/browser/ui/authentication/signin_interaction_controller.mm

 // Copyright 2014 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 "ios/chrome/browser/ui/authentication/signin_interaction_controller.h"
 
-#include "base/ios/weak_nsobject.h"
 #include "base/logging.h"
 #include "base/mac/scoped_block.h"
 #include "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #include "components/prefs/pref_service.h"
 #include "components/signin/core/browser/signin_manager.h"
 #include "components/signin/core/common/signin_pref_names.h"
 #import "ios/chrome/browser/browser_state/chrome_browser_state.h"
 #include "ios/chrome/browser/signin/authentication_service.h"
 #include "ios/chrome/browser/signin/authentication_service_factory.h"
 #include "ios/chrome/browser/signin/signin_manager_factory.h"
 #import "ios/chrome/browser/signin/signin_util.h"
 #import "ios/chrome/browser/ui/alert_coordinator/alert_coordinator.h"
 #import "ios/chrome/browser/ui/authentication/authentication_ui_util.h"
 #import "ios/chrome/browser/ui/authentication/chrome_signin_view_controller.h"
 #import "ios/chrome/browser/ui/commands/UIKit+ChromeExecuteCommand.h"
 #import "ios/chrome/browser/ui/util/top_view_controller.h"
 #import "ios/public/provider/chrome/browser/chrome_browser_provider.h"
 #import "ios/public/provider/chrome/browser/signin/chrome_identity.h"
 #import "ios/public/provider/chrome/browser/signin/chrome_identity_interaction_manager.h"
 #import "ios/public/provider/chrome/browser/signin/chrome_identity_service.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 using signin_ui::CompletionCallback;
 
 @interface SigninInteractionController ()<
     ChromeIdentityInteractionManagerDelegate,
     ChromeSigninViewControllerDelegate> {
   ios::ChromeBrowserState* browserState_;
   signin_metrics::AccessPoint accessPoint_;
   signin_metrics::PromoAction promoAction_;
-  base::scoped_nsobject<UIViewController> presentingViewController_;
+  UIViewController* presentingViewController_;
   BOOL isPresentedOnSettings_;
   BOOL isCancelling_;
   BOOL isDismissing_;
   BOOL interactionManagerDismissalIgnored_;
-  base::scoped_nsobject<AlertCoordinator> alertCoordinator_;
-  base::mac::ScopedBlock<CompletionCallback> completionCallback_;
-  base::scoped_nsobject<ChromeSigninViewController> signinViewController_;
-  base::scoped_nsobject<ChromeIdentityInteractionManager>
-      identityInteractionManager_;
-  base::scoped_nsobject<ChromeIdentity> signInIdentity_;
+  AlertCoordinator* alertCoordinator_;
+  CompletionCallback completionCallback_;
+  ChromeSigninViewController* signinViewController_;
+  ChromeIdentityInteractionManager* identityInteractionManager_;
+  ChromeIdentity* signInIdentity_;
   BOOL identityAdded_;
 }
 @end
 
 @implementation SigninInteractionController
 
 - (id)init {
   NOTREACHED();
   return nil;
 }
 
 - (instancetype)initWithBrowserState:(ios::ChromeBrowserState*)browserState
             presentingViewController:(UIViewController*)presentingViewController
                isPresentedOnSettings:(BOOL)isPresentedOnSettings
                          accessPoint:(signin_metrics::AccessPoint)accessPoint
                          promoAction:(signin_metrics::PromoAction)promoAction {
   self = [super init];
   if (self) {
     DCHECK(browserState);
     DCHECK(presentingViewController);
     browserState_ = browserState;
-    presentingViewController_.reset([presentingViewController retain]);
+    presentingViewController_ = presentingViewController;
     isPresentedOnSettings_ = isPresentedOnSettings;
     accessPoint_ = accessPoint;
     promoAction_ = promoAction;
   }
   return self;
 }
 
 - (void)cancel {
   // Cancelling and dismissing the |identityInteractionManager_| may call the
   // |completionCallback_| which could lead to |self| being released before the
   // end of this method. |self| is retained here to prevent this from happening.
-  base::scoped_nsobject<SigninInteractionController> strongSelf([self retain]);
+  base::scoped_nsobject<SigninInteractionController> strongSelf(self);

[msarda, 2017/06/12 12:49:13]

Is this correct? I t there should not be any usage of scoped_nsobject left after
migrating to ARC.

[marq (ping after 24h), 2017/06/12 14:20:40]

I had kept it there because I didn't know what the behavior of an unused strong
pointer under ARC would be, but I guess (after thinking about it) that it would
work fine. It looks like some other classes do the same thing.

   isCancelling_ = YES;
   [alertCoordinator_ executeCancelHandler];
   [alertCoordinator_ stop];
   [identityInteractionManager_ cancelAndDismissAnimated:NO];
   [signinViewController_ cancel];
   isCancelling_ = NO;
 }
 
 - (void)cancelAndDismiss {
   isDismissing_ = YES;
   [self cancel];
   isDismissing_ = NO;
 }
 
 - (void)signInWithViewController:(UIViewController*)viewController
                         identity:(ChromeIdentity*)identity
                       completion:(signin_ui::CompletionCallback)completion {
   signin_metrics::LogSigninAccessPointStarted(accessPoint_, promoAction_);
-  completionCallback_.reset(completion, base::scoped_policy::RETAIN);
+  completionCallback_ = completion;

[msarda, 2017/06/12 12:49:13]

Here and everywhere else we use ScopedBlock with RETAIN policy:

I think the retain policy actually lead to a copy of the block - see
https://cs.chromium.org/chromium/src/base/mac/scoped_block.h?rcl=feb596f1bd91...
.

I think this will no longer be the case (the block will just be retained, not
copied). 

[marq (ping after 24h), 2017/06/12 14:20:40]

Changed all simple assignments to [foo copy].

   ios::ChromeIdentityService* identityService =
       ios::GetChromeBrowserProvider()->GetChromeIdentityService();
   if (identity) {
     DCHECK(identityService->IsValidIdentity(identity));
     DCHECK(!signinViewController_);
     [self showSigninViewControllerWithIdentity:identity identityAdded:NO];
   } else if (identityService->HasIdentities()) {
     DCHECK(!signinViewController_);
     [self showSigninViewControllerWithIdentity:nil identityAdded:NO];
   } else {
     identityInteractionManager_ =
         identityService->NewChromeIdentityInteractionManager(browserState_,
                                                              self);
     if (!identityInteractionManager_) {
       // Abort sign-in if the ChromeIdentityInteractionManager returned is
       // nil (this can happen when the iOS internal provider is not used).
       [self runCompletionCallbackWithSuccess:NO executeCommand:nil];
       return;
     }
 
-    base::WeakNSObject<SigninInteractionController> weakSelf(self);
+    __weak SigninInteractionController* weakSelf = self;
     [identityInteractionManager_
         addAccountWithCompletion:^(ChromeIdentity* identity, NSError* error) {
           [weakSelf handleIdentityAdded:identity
                                   error:error
                            shouldSignIn:YES
                          viewController:viewController];
         }];
   }
 }
 
 - (void)reAuthenticateWithCompletion:(CompletionCallback)completion
                       viewController:(UIViewController*)viewController {
   signin_metrics::LogSigninAccessPointStarted(accessPoint_, promoAction_);
-  completionCallback_.reset(completion, base::scoped_policy::RETAIN);
+  completionCallback_ = completion;
   AccountInfo accountInfo =
       ios::SigninManagerFactory::GetForBrowserState(browserState_)
           ->GetAuthenticatedAccountInfo();
   std::string emailToReauthenticate = accountInfo.email;
   std::string idToReauthenticate = accountInfo.gaia;
   if (emailToReauthenticate.empty() || idToReauthenticate.empty()) {
     // This corresponds to a re-authenticate request after the user was signed
     // out. This corresponds to the case where the identity was removed as a
     // result of the permissions being removed on the server or the identity
     // being removed from another app.
     //
     // Simply use the the last signed-in user email in this case and go though
     // the entire sign-in flow as sync needs to be configured.
     emailToReauthenticate = browserState_->GetPrefs()->GetString(
         prefs::kGoogleServicesLastUsername);
     idToReauthenticate = browserState_->GetPrefs()->GetString(
         prefs::kGoogleServicesLastAccountId);
   }
   DCHECK(!emailToReauthenticate.empty());
   DCHECK(!idToReauthenticate.empty());
   identityInteractionManager_ =
       ios::GetChromeBrowserProvider()
           ->GetChromeIdentityService()
           ->NewChromeIdentityInteractionManager(browserState_, self);
-  base::WeakNSObject<SigninInteractionController> weakSelf(self);
+  __weak SigninInteractionController* weakSelf = self;
   [identityInteractionManager_
       reauthenticateUserWithID:base::SysUTF8ToNSString(idToReauthenticate)
                          email:base::SysUTF8ToNSString(emailToReauthenticate)
                     completion:^(ChromeIdentity* identity, NSError* error) {
                       [weakSelf handleIdentityAdded:identity
                                               error:error
                                        shouldSignIn:YES
                                      viewController:viewController];
                     }];
 }
 
 - (void)addAccountWithCompletion:(CompletionCallback)completion
                   viewController:(UIViewController*)viewController {
-  completionCallback_.reset(completion, base::scoped_policy::RETAIN);
+  completionCallback_ = completion;
   identityInteractionManager_ =
       ios::GetChromeBrowserProvider()
           ->GetChromeIdentityService()
           ->NewChromeIdentityInteractionManager(browserState_, self);
-  base::WeakNSObject<SigninInteractionController> weakSelf(self);
+  __weak SigninInteractionController* weakSelf = self;
   [identityInteractionManager_
       addAccountWithCompletion:^(ChromeIdentity* identity, NSError* error) {
         [weakSelf handleIdentityAdded:identity
                                 error:error
                          shouldSignIn:NO
                        viewController:viewController];
       }];
 }
 
 #pragma mark - ChromeIdentityInteractionManager operations
 
 - (void)handleIdentityAdded:(ChromeIdentity*)identity
                       error:(NSError*)error
                shouldSignIn:(BOOL)shouldSignIn
              viewController:(UIViewController*)viewController {
   if (!identityInteractionManager_)
     return;
 
   if (error) {
     // Filter out cancel and errors handled internally by ChromeIdentity.
     if (!ShouldHandleSigninError(error)) {
       [self runCompletionCallbackWithSuccess:NO executeCommand:nil];
       return;
     }
 
-    base::WeakNSObject<SigninInteractionController> weakSelf(self);
+    __weak SigninInteractionController* weakSelf = self;
     ProceduralBlock dismissAction = ^{
       [weakSelf runCompletionCallbackWithSuccess:NO executeCommand:nil];
     };
 
-    alertCoordinator_.reset([ios_internal::ErrorCoordinator(
+    alertCoordinator_ = ios_internal::ErrorCoordinator(
         error, dismissAction,
-        top_view_controller::TopPresentedViewControllerFrom(viewController))
-        retain]);
+        top_view_controller::TopPresentedViewControllerFrom(viewController));
     [alertCoordinator_ start];
     return;
   }
   if (shouldSignIn) {
     [self showSigninViewControllerWithIdentity:identity identityAdded:YES];
   } else {
     [self runCompletionCallbackWithSuccess:YES executeCommand:nil];
   }
 }
 
@@ skipping 34 matching lines @@
     if (completion) {
       completion();
     }
   }
 }
 
 #pragma mark - ChromeSigninViewController operations
 
 - (void)showSigninViewControllerWithIdentity:(ChromeIdentity*)signInIdentity
                                identityAdded:(BOOL)identityAdded {
-  signinViewController_.reset([[ChromeSigninViewController alloc]
+  signinViewController_ = [[ChromeSigninViewController alloc]
        initWithBrowserState:browserState_
       isPresentedOnSettings:isPresentedOnSettings_
                 accessPoint:accessPoint_
                 promoAction:promoAction_
-             signInIdentity:signInIdentity]);
+             signInIdentity:signInIdentity];
   [signinViewController_ setDelegate:self];
   [signinViewController_
       setModalPresentationStyle:UIModalPresentationFormSheet];
   [signinViewController_
       setModalTransitionStyle:UIModalTransitionStyleCoverVertical];
-  signInIdentity_.reset([signInIdentity retain]);
+  signInIdentity_ = signInIdentity;
   identityAdded_ = identityAdded;
 
   UIViewController* presentingViewController = presentingViewController_;
   if (identityInteractionManager_) {
     // If |identityInteractionManager_| is currently displayed,
     // |signinViewController_| is presented on top of it (instead of on top of
     // |presentingViewController_|), to avoid an awkward transition (dismissing
     // |identityInteractionManager_|, followed by presenting
     // |signinViewController_|).
     while (presentingViewController.presentedViewController) {
@@ skipping 17 matching lines @@
   }
   ProceduralBlock completion = ^{
     [self runCompletionCallbackWithSuccess:success executeCommand:command];
   };
   [self dismissPresentedViewControllersAnimated:YES completion:completion];
 }
 
 #pragma mark - ChromeSigninViewControllerDelegate
 
 - (void)willStartSignIn:(ChromeSigninViewController*)controller {
-  DCHECK_EQ(controller, signinViewController_.get());
+  DCHECK_EQ(controller, signinViewController_);
 }
 
 - (void)willStartAddAccount:(ChromeSigninViewController*)controller {
-  DCHECK_EQ(controller, signinViewController_.get());
+  DCHECK_EQ(controller, signinViewController_);
 }
 
 - (void)didSkipSignIn:(ChromeSigninViewController*)controller {
-  DCHECK_EQ(controller, signinViewController_.get());
+  DCHECK_EQ(controller, signinViewController_);
   [self dismissSigninViewControllerWithSignInSuccess:NO executeCommand:nil];
 }
 
 - (void)didSignIn:(ChromeSigninViewController*)controller {
-  DCHECK_EQ(controller, signinViewController_.get());
+  DCHECK_EQ(controller, signinViewController_);
 }
 
 - (void)didUndoSignIn:(ChromeSigninViewController*)controller
              identity:(ChromeIdentity*)identity {
-  DCHECK_EQ(controller, signinViewController_.get());
-  if ([signInIdentity_.get() isEqual:identity]) {
-    signInIdentity_.reset();
+  DCHECK_EQ(controller, signinViewController_);
+  if ([signInIdentity_ isEqual:identity]) {
+    signInIdentity_ = nil;
     if (identityAdded_) {
       // This is best effort. If the operation fails, the account will be left
       // on the device. The user will not be warned either as this call is
       // asynchronous (but undo is not), the application might be in an unknown
       // state when the forget identity operation finishes.
       ios::GetChromeBrowserProvider()
           ->GetChromeIdentityService()
           ->ForgetIdentity(identity, nil);
     }
     [self dismissSigninViewControllerWithSignInSuccess:NO executeCommand:nil];
   }
 }
 
 - (void)didFailSignIn:(ChromeSigninViewController*)controller {
-  DCHECK_EQ(controller, signinViewController_.get());
+  DCHECK_EQ(controller, signinViewController_);
   [self dismissSigninViewControllerWithSignInSuccess:NO executeCommand:nil];
 }
 
 - (void)didAcceptSignIn:(ChromeSigninViewController*)controller
          executeCommand:(GenericChromeCommand*)command {
-  DCHECK_EQ(controller, signinViewController_.get());
+  DCHECK_EQ(controller, signinViewController_);
   [self dismissSigninViewControllerWithSignInSuccess:YES
                                       executeCommand:command];
 }
 
 #pragma mark - Utility methods
 
 - (void)runCompletionCallbackWithSuccess:(BOOL)success
                           executeCommand:(GenericChromeCommand*)command {
   // In order to avoid awkward double transitions, |identityInteractionManager_|
   // is not dismissed when requested (except when canceling). However, in case
   // of errors, |identityInteractionManager_| needs to be directly dismissed,
   // which is done here.
   if (interactionManagerDismissalIgnored_) {
     [self dismissPresentedViewControllersAnimated:YES completion:nil];
   }
 
-  identityInteractionManager_.reset();
-  signinViewController_.reset();
+  identityInteractionManager_ = nil;
+  signinViewController_ = nil;
   UIViewController* presentingViewController = presentingViewController_;
   // Ensure self is not destroyed in the callbacks.
-  base::scoped_nsobject<SigninInteractionController> strongSelf([self retain]);
+  SigninInteractionController* strongSelf = self;
   if (completionCallback_) {
-    completionCallback_.get()(success);
-    completionCallback_.reset();
+    completionCallback_(success);
+    completionCallback_ = nil;
   }
-  strongSelf.reset();
+  strongSelf = nil;
   if (command) {
     [presentingViewController chromeExecuteCommand:command];
   }
 }
 
 @end