Refactor Assert[No]CookieExists to return a boolean

ios/chrome/browser/ui/settings/settings_egtest.mm

 // Copyright 2016 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 <EarlGrey/EarlGrey.h>
 #import <UIKit/UIKit.h>
 #import <XCTest/XCTest.h>
 #include <map>
 
 #include "base/bind.h"
@@ skipping 146 matching lines @@
 }
 // Matcher for the Privacy Translate Settings button on the privacy UI.
 id<GREYMatcher> TranslateSettingsButton() {
   return ButtonWithAccessibilityLabelId(IDS_IOS_TRANSLATE_SETTING);
 }
 // Matcher for the save button in the save password bar.
 id<GREYMatcher> savePasswordButton() {
   return ButtonWithAccessibilityLabelId(IDS_IOS_PASSWORD_MANAGER_SAVE_BUTTON);
 }
 
-// Asserts that there is no cookie in current web state.
-void AssertNoCookieExists() {
+// Returns true if there is no cookie in current web state.
+bool WebStateHasNoCookie() {
+  chrome_test_util::ExecuteJavaScript(
+      base::SysUTF8ToNSString(kJavaScriptGetCookies), nil);
   NSError* error = nil;
-  chrome_test_util::ExecuteJavaScript(
-      base::SysUTF8ToNSString(kJavaScriptGetCookies), &error);
   [[EarlGrey selectElementWithMatcher:chrome_test_util::WebViewContainingText(
                                           kNoCookieText)]
-      assertWithMatcher:grey_notNil()];
+      assertWithMatcher:grey_notNil()
+                  error:&error];
+
+  return error == nil;
 }
 
-// Asserts |cookie| exists in current web state.
-void AssertCookieExists(const char cookie[]) {
-  NSError* error = nil;
+// Returns true if |cookie| is the only cookie exists in current web state.

[baxley, 2017/03/08 16:20:50]

will this return true if it's the "only" cookie? Is there a way to have multiple
cookies and it return true?

[liaoyuke, 2017/03/08 21:27:26]

Resolved per offline discussion.

+bool WebStateHasCookie(const char cookie[]) {
   chrome_test_util::ExecuteJavaScript(
-      base::SysUTF8ToNSString(kJavaScriptGetCookies), &error);
+      base::SysUTF8ToNSString(kJavaScriptGetCookies), nil);
   NSString* const expectedCookieText =
       [NSString stringWithFormat:@"OK: %@", base::SysUTF8ToNSString(cookie)];
+  NSError* error = nil;
   [[EarlGrey
       selectElementWithMatcher:chrome_test_util::WebViewContainingText(
                                    base::SysNSStringToUTF8(expectedCookieText))]
-      assertWithMatcher:grey_notNil()];
+      assertWithMatcher:grey_notNil()
+                  error:&error];

[baxley, 2017/03/08 16:20:50]

Sorry, I'm not great at reading regex. Could you clarify why this would return
false for the case where there are two cookies, and we're checking for the first
one?

[liaoyuke, 2017/03/08 21:27:26]

Resolved per offline discussion.

+  return error == nil;
 }
 
 // Run as a task to check if a certificate has been added to the ChannelIDStore.
 // Signals the given |semaphore| if the cert was added, or reposts itself
 // otherwise.
 void CheckCertificate(scoped_refptr<net::URLRequestContextGetter> getter,
                       dispatch_semaphore_t semaphore) {
   net::ChannelIDService* channel_id_service =
       getter->GetURLRequestContext()->channel_id_service();
   if (channel_id_service->channel_id_count() == 0) {
@@ skipping 482 matching lines @@
   response[web::test::HttpServer::MakeUrl(kUrl)] =
       std::pair<std::string, std::string>("", kResponse);
 
   web::test::SetUpSimpleHttpServerWithSetCookies(response);
 
   // Load |kUrl| and check that cookie is not set.
   [ChromeEarlGrey loadURL:web::test::HttpServer::MakeUrl(kUrl)];
   [[EarlGrey selectElementWithMatcher:chrome_test_util::WebViewContainingText(
                                           kResponse)]
       assertWithMatcher:grey_notNil()];
-  AssertNoCookieExists();
+
+  GREYAssertTrue(WebStateHasNoCookie(),
+                 @"Web state is expected to have no cookie.");
 
   // Visit |kUrlWithSetCookie| to set a cookie and then load |kUrl| to check it
   // is still set.
   [ChromeEarlGrey loadURL:web::test::HttpServer::MakeUrl(kUrlWithSetCookie)];
   [[EarlGrey selectElementWithMatcher:chrome_test_util::WebViewContainingText(
                                           kResponseWithSetCookie)]
       assertWithMatcher:grey_notNil()];
   [ChromeEarlGrey loadURL:web::test::HttpServer::MakeUrl(kUrl)];
   [[EarlGrey selectElementWithMatcher:chrome_test_util::WebViewContainingText(
                                           kResponse)]
       assertWithMatcher:grey_notNil()];
 
-  AssertCookieExists(kCookie);
+  NSString* const errorMessage = [NSString
+      stringWithFormat:@"Web state is expected to have following cookie: %@.",
+                       base::SysUTF8ToNSString(kCookie)];
+  GREYAssertTrue(WebStateHasCookie(kCookie), errorMessage);
 
   // Restore the Clear Browsing Data checkmarks prefs to their default state in
   // Teardown.
   [self setTearDownHandler:^{
     [self restoreClearBrowsingDataCheckmarksToDefault];
   }];
 
   // Clear all cookies.
   [self clearCookiesAndSiteData];
 
   // Reload and test that there are no cookies left.
   [ChromeEarlGrey loadURL:web::test::HttpServer::MakeUrl(kUrl)];
   [[EarlGrey selectElementWithMatcher:chrome_test_util::WebViewContainingText(
                                           kResponse)]
       assertWithMatcher:grey_notNil()];
-  AssertNoCookieExists();
+  GREYAssertTrue(WebStateHasNoCookie(),
+                 @"Web state is expected to have no cookie.");
   chrome_test_util::CloseAllTabs();
 }
 
 // Verifies that logging into a form on a web page allows the user to save and
 // then clear a password.
 - (void)testClearPasswords {
 
   ios::ChromeBrowserState* browserState =
       chrome_test_util::GetOriginalBrowserState();
   PrefService* preferences = browserState->GetPrefs();
@@ skipping 325 matching lines @@
       performAction:grey_tap()];
   [[EarlGrey selectElementWithMatcher:PrivacyButton()]
       performAction:grey_tap()];
   [[EarlGrey selectElementWithMatcher:SendUsageDataButton()]
       performAction:grey_tap()];
   chrome_test_util::VerifyAccessibilityForCurrentScreen();
   [self closeSubSettingsMenu];
 }
 
 @end