Upstream Chrome on iOS source code [10/11].

ios/chrome/test/earl_grey/chrome_earl_grey.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 "ios/chrome/test/earl_grey/chrome_earl_grey.h"
+
+#import <Foundation/Foundation.h>
+#import <WebKit/WebKit.h>
+
+#include "base/strings/sys_string_conversions.h"
+#import "ios/chrome/test/app/chrome_test_util.h"
+#include "ios/chrome/test/app/history_test_util.h"
+#include "ios/chrome/test/app/navigation_test_util.h"
+#import "ios/testing/wait_util.h"
+#import "ios/web/public/test/earl_grey/js_test_util.h"
+#import "ios/web/public/test/web_view_interaction_test_util.h"
+#import "ios/web/public/web_state/js/crw_js_injection_receiver.h"
+#include "ios/web/public/web_state/web_state.h"
+
+namespace chrome_test_util {
+
+id ExecuteJavaScript(NSString* javascript, NSError** out_error) {
+  __block bool did_complete = false;
+  __block id result = nil;
+  __block NSError* temp_error = nil;
+  CRWJSInjectionReceiver* evaluator =
+      chrome_test_util::GetCurrentWebState()->GetJSInjectionReceiver();
+  [evaluator executeJavaScript:javascript
+             completionHandler:^(id value, NSError* error) {
+               did_complete = true;
+               result = [value copy];
+               temp_error = [error copy];
+             }];
+
+  // Wait for completion.
+  GREYCondition* condition = [GREYCondition
+      conditionWithName:@"Wait for JavaScript execution to complete."
+                  block:^BOOL {
+                    return did_complete;
+                  }];
+  [condition waitWithTimeout:testing::kWaitForJSCompletionTimeout];
+  if (!did_complete)
+    return nil;
+  [temp_error autorelease];
+  if (out_error)
+    *out_error = temp_error;
+  return [result autorelease];
+}
+
+}  // namespace chrome_test_util
+
+@implementation ChromeEarlGrey
+
+#pragma mark - History Utilities
+
++ (void)clearBrowsingHistory {
+  chrome_test_util::ClearBrowsingHistory();
+  // After clearing browsing history via code, wait for the UI to be done
+  // with any updates. This includes icons from the new tab page being removed.
+  [[GREYUIThreadExecutor sharedInstance] drainUntilIdle];
+}
+
+#pragma mark - Navigation Utilities
+
++ (void)loadURL:(GURL)URL {
+  chrome_test_util::LoadUrl(URL);
+  // Make sure that the page started loading.
+  GREYAssert(chrome_test_util::IsLoading(), @"Page did not start loading.");
+  [ChromeEarlGrey waitForPageToFinishLoading];
+
+  web::WebState* webState = chrome_test_util::GetCurrentWebState();
+  if (webState->ContentIsHTML())
+    web::WaitUntilWindowIdInjected(webState);
+}
+
++ (void)waitForPageToFinishLoading {
+  GREYCondition* condition =
+      [GREYCondition conditionWithName:@"Wait for page to complete loading."
+                                 block:^BOOL {
+                                   return !chrome_test_util::IsLoading();
+                                 }];
+  GREYAssert([condition waitWithTimeout:testing::kWaitForPageLoadTimeout],
+             @"Page did not complete loading.");
+}
+
++ (void)tapWebViewElementWithID:(NSString*)elementID {
+  BOOL success =
+      web::test::TapWebViewElementWithId(chrome_test_util::GetCurrentWebState(),
+                                         base::SysNSStringToUTF8(elementID));
+  GREYAssertTrue(
+      success,
+      [NSString stringWithFormat:@"Failed to tap web view element with ID: %@",
+                                 elementID]);
+}
+
+@end