Change CWVAutofillDataManagerDelegate to CWVAutofillDataManagerObservers

Since there many be multiple objects interested in data changes, it's
more natural to use an observer pattern instead.

Change-Id: Ib7e291626bf3f3dce23a73ebc329f96bc8f9deb9
Reviewed-on: https://chromium-review.googlesource.com/c/1293990
Commit-Queue: John Wu <jzw@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601662}

ios/web_view/BUILD.gn

@@ -80,7 +80,7 @@ if (ios_web_view_enable_autofill) {
     "public/cwv_autofill_controller.h",
     "public/cwv_autofill_controller_delegate.h",
     "public/cwv_autofill_data_manager.h",
-    "public/cwv_autofill_data_manager_delegate.h",
+    "public/cwv_autofill_data_manager_observer.h",
     "public/cwv_autofill_profile.h",
     "public/cwv_autofill_suggestion.h",
     "public/cwv_credit_card.h",

ios/web_view/internal/autofill/cwv_autofill_data_manager.mm

@@ -14,7 +14,7 @@
 #include "ios/web/public/web_thread.h"
 #import "ios/web_view/internal/autofill/cwv_autofill_profile_internal.h"
 #import "ios/web_view/internal/autofill/cwv_credit_card_internal.h"
-#import "ios/web_view/public/cwv_autofill_data_manager_delegate.h"
+#import "ios/web_view/public/cwv_autofill_data_manager_observer.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
@@ -73,10 +73,10 @@ class WebViewPersonalDataManagerObserverBridge
       _fetchProfilesCompletionHandlers;
   NSMutableArray<CWVFetchCreditCardsCompletionHandler>*
       _fetchCreditCardsCompletionHandlers;
+  // Holds weak observers.
+  NSHashTable<id<CWVAutofillDataManagerObserver>>* _observers;
 }
 
-@synthesize delegate = _delegate;
-
 - (instancetype)initWithPersonalDataManager:
     (autofill::PersonalDataManager*)personalDataManager {
   self = [super init];
@@ -87,6 +87,7 @@ class WebViewPersonalDataManagerObserverBridge
     _personalDataManager->AddObserver(_personalDataManagerObserverBridge.get());
     _fetchProfilesCompletionHandlers = [NSMutableArray array];
     _fetchCreditCardsCompletionHandlers = [NSMutableArray array];
+    _observers = [NSHashTable weakObjectsHashTable];
   }
   return self;
 }
@@ -98,6 +99,14 @@ class WebViewPersonalDataManagerObserverBridge
 
 #pragma mark - Public Methods
 
+- (void)addObserver:(__weak id<CWVAutofillDataManagerObserver>)observer {
+  [_observers addObject:observer];
+}
+
+- (void)removeObserver:(__weak id<CWVAutofillDataManagerObserver>)observer {
+  [_observers removeObject:observer];
+}
+
 - (void)fetchProfilesWithCompletionHandler:
     (void (^)(NSArray<CWVAutofillProfile*>* profiles))completionHandler {
   // If data is already loaded, return the existing data asynchronously to match
@@ -172,7 +181,9 @@ class WebViewPersonalDataManagerObserverBridge
       [_fetchCreditCardsCompletionHandlers removeAllObjects];
     }
   }
-  [_delegate autofillDataManagerDataDidChange:self];
+  for (id<CWVAutofillDataManagerObserver> observer in _observers) {
+    [observer autofillDataManagerDataDidChange:self];
+  }
 }
 
 - (NSArray<CWVAutofillProfile*>*)profiles {

ios/web_view/internal/autofill/cwv_autofill_data_manager_unittest.mm

@@ -16,7 +16,7 @@
 #include "ios/web/public/test/test_web_thread_bundle.h"
 #import "ios/web_view/internal/autofill/cwv_autofill_profile_internal.h"
 #import "ios/web_view/internal/autofill/cwv_credit_card_internal.h"
-#import "ios/web_view/public/cwv_autofill_data_manager_delegate.h"
+#import "ios/web_view/public/cwv_autofill_data_manager_observer.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #import "testing/gtest_mac.h"
 #include "testing/platform_test.h"
@@ -101,16 +101,20 @@ class CWVAutofillDataManagerTest : public PlatformTest {
 
 // Tests CWVAutofillDataManager properly invokes did change callback.
 TEST_F(CWVAutofillDataManagerTest, DidChangeCallback) {
-  id delegate = OCMProtocolMock(@protocol(CWVAutofillDataManagerDelegate));
-  autofill_data_manager_.delegate = delegate;
-
-  // [delegate expect] returns an autoreleased object, but it must be destroyed
-  // before this test exits to avoid holding on to |autofill_data_manager_|.
+  // OCMock objects are often autoreleased, but it must be destroyed before this
+  // test exits to avoid holding on to |autofill_data_manager_|.
   @autoreleasepool {
-    [[delegate expect] autofillDataManagerDataDidChange:autofill_data_manager_];
+    id observer = OCMProtocolMock(@protocol(CWVAutofillDataManagerObserver));
+
+    [autofill_data_manager_ addObserver:observer];
+    [[observer expect] autofillDataManagerDataDidChange:autofill_data_manager_];
     personal_data_manager_->AddProfile(autofill::test::GetFullProfile());
+    [observer verify];
 
-    [delegate verify];
+    [autofill_data_manager_ removeObserver:observer];
+    [[observer reject] autofillDataManagerDataDidChange:autofill_data_manager_];
+    personal_data_manager_->AddProfile(autofill::test::GetFullProfile2());
+    [observer verify];
   }
 }
 

ios/web_view/public/cwv_autofill_data_manager.h

@@ -13,17 +13,20 @@ NS_ASSUME_NONNULL_BEGIN
 
 @class CWVAutofillProfile;
 @class CWVCreditCard;
-@protocol CWVAutofillDataManagerDelegate;
+@protocol CWVAutofillDataManagerObserver;
 
 CWV_EXPORT
 // Exposes saved autofill data such as address profiles and credit cards.
 @interface CWVAutofillDataManager : NSObject
 
-// Delegate for CWVAutofillDataManagerDelegate.
-@property(nonatomic, weak) id<CWVAutofillDataManagerDelegate> delegate;
-
 - (instancetype)init NS_UNAVAILABLE;
 
+// Adds |observer| for data changes.
+- (void)addObserver:(__weak id<CWVAutofillDataManagerObserver>)observer;
+
+// Removes |observer| that was previously added with |addObserver|.
+- (void)removeObserver:(__weak id<CWVAutofillDataManagerObserver>)observer;
+
 // Returns all saved profiles for address autofill in |completionHandler|.
 - (void)fetchProfilesWithCompletionHandler:
     (void (^)(NSArray<CWVAutofillProfile*>* profiles))completionHandler;

ios/web_view/public/cwv_autofill_data_manager_delegate.h → ios/web_view/public/cwv_autofill_data_manager_observer.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef IOS_WEB_VIEW_PUBLIC_CWV_AUTOFILL_DATA_MANAGER_DELEGATE_H_
-#define IOS_WEB_VIEW_PUBLIC_CWV_AUTOFILL_DATA_MANAGER_DELEGATE_H_
+#ifndef IOS_WEB_VIEW_PUBLIC_CWV_AUTOFILL_DATA_MANAGER_OBSERVER_H_
+#define IOS_WEB_VIEW_PUBLIC_CWV_AUTOFILL_DATA_MANAGER_OBSERVER_H_
 
 #import <Foundation/Foundation.h>
 
@@ -12,7 +12,7 @@ NS_ASSUME_NONNULL_BEGIN
 @class CWVAutofillDataManager;
 
 // Protocol to receive change notifications from CWVAutofillDataManager.
-@protocol CWVAutofillDataManagerDelegate<NSObject>
+@protocol CWVAutofillDataManagerObserver<NSObject>
 
 // Called whenever CWVAutofillDataManager's autofill profiles or credit cards
 // have been loaded for the first time, added, deleted, or updated.
@@ -23,4 +23,4 @@ NS_ASSUME_NONNULL_BEGIN
 
 NS_ASSUME_NONNULL_END
 
-#endif  // IOS_WEB_VIEW_PUBLIC_CWV_AUTOFILL_DATA_MANAGER_DELEGATE_H_
+#endif  // IOS_WEB_VIEW_PUBLIC_CWV_AUTOFILL_DATA_MANAGER_OBSERVER_H_