Created test for restoring state object after back/forward navigation.

ios/web/navigation/history_state_operations_inttest.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 "base/mac/bind_objc_block.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/stringprintf.h"
 #import "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/ios/wait_util.h"
@@ skipping 116 matching lines @@
   // Instructs |observer_| to wait for a successful load event for |url|.
   void ExpectPageLoad(const GURL& url) { observer_->ExpectPageLoad(url); }
 
   // Waits until |observer_| reports that a load has finished successfully.
   void WaitForPageToLoad() {
     base::test::ios::WaitUntilCondition(^bool {
       return observer_->IsExpectedPageLoaded();
     });
   }
 
+  // Executes |block| and waits for |url| to be successfully loaded.
+  void ExecuteBlockAndWaitForLoad(const GURL& url, ProceduralBlock block) {
+    ExpectPageLoad(url);
+    block();
+    WaitForPageToLoad();
+  }
+
   // Loads |url| in |web_state_|.
   void LoadUrl(const GURL& url) {
-    ExpectPageLoad(url);
-    web::NavigationManager::WebLoadParams params(url);
-    navigation_manager()->LoadURLWithParams(params);
-    WaitForPageToLoad();
+    ExecuteBlockAndWaitForLoad(url, ^{
+      web::NavigationManager::WebLoadParams params(url);
+      navigation_manager()->LoadURLWithParams(params);
+    });
   }
 
   // Reloads the page and waits for the load to finish.
   void Reload() {
-    ExpectPageLoad(current_item()->GetURL());
-    // TODO(crbug.com/677364): Use NavigationManager::Reload() once it no longer
-    // requires a web delegate.
-    web_state()->ExecuteJavaScript(ASCIIToUTF16("window.location.reload()"));
-    WaitForPageToLoad();
+    ExecuteBlockAndWaitForLoad(current_item()->GetURL(), ^{
+      // TODO(crbug.com/677364): Use NavigationManager::Reload() once it no
+      // longer requires a web delegate.
+      web_state()->ExecuteJavaScript(ASCIIToUTF16("window.location.reload()"));
+    });
   }
 
   // Set the parameters to use for state operations on the test page.
   void SetStateParams(const std::string& state_object,
                       const std::string& title,
                       const GURL& url) {
     ASSERT_EQ(state_operations_url(), current_item()->GetURL());
     std::string url_spec = url.possibly_invalid_spec();
     base::string16 set_params_script = ASCIIToUTF16(
         StringPrintf(kUpdateStateParamsScriptFormat, state_object.c_str(),
@@ skipping 203 matching lines @@
               result->GetAsString(&state);
               state_object_present = state == new_state;
             }));
       },
       ^bool {
         return state_object_present;
       },
       false, base::TimeDelta::FromSeconds(10.0));
   EXPECT_TRUE(state_object_present);
 }
+
+// Tests that the state object is correctly set for a page after a back/forward
+// navigation.
+TEST_F(HistoryStateOperationsTest, StateReplacementBackForward) {
+  // Navigate to about:blank then navigate back to the test page.  The created
+  // NavigationItem can be used later to verify that the state is replaced
+  // rather than pushed.
+  GURL about_blank("about:blank");
+  LoadUrl(about_blank);
+  ExecuteBlockAndWaitForLoad(state_operations_url(), ^{
+    navigation_manager()->GoBack();
+  });
+  ASSERT_EQ(state_operations_url(), current_item()->GetURL());
+  // Set up the state parameters and tap the replace state button.
+  std::string new_state("STATE OBJECT");
+  std::string empty_title("");

[Eugene But (OOO till 7-30), 2016/12/29 17:19:24]

std::string empty_title;

[kkhorimoto, 2017/01/24 05:22:54]

Done.

+  GURL empty_url("");

[Eugene But (OOO till 7-30), 2016/12/29 17:19:24]

GURL empty_url;

[kkhorimoto, 2017/01/24 05:22:54]

Done.

+  SetStateParams(new_state, empty_title, empty_url);
+  ASSERT_TRUE(web::test::TapWebViewElementWithId(web_state(), kReplaceStateID));
+  // Go forward and back, then check that the state object is present.
+  ExecuteBlockAndWaitForLoad(about_blank, ^{
+    navigation_manager()->GoForward();
+  });
+  ExecuteBlockAndWaitForLoad(state_operations_url(), ^{
+    navigation_manager()->GoBack();
+  });
+  ASSERT_TRUE(IsOnLoadTextVisible());
+  __block bool state_object_present = false;
+  base::string16 state_object_script = ASCIIToUTF16("window.history.state");
+  base::test::ios::TimeUntilCondition(
+      ^{
+        web_state()->ExecuteJavaScript(

[Eugene But (OOO till 7-30), 2016/12/29 17:19:24]

Please use synchronous API.

[kkhorimoto, 2017/01/24 05:22:54]

Done.

+            state_object_script, base::BindBlock(^(const base::Value* result) {
+              std::string state;
+              result->GetAsString(&state);
+              state_object_present = state == new_state;
+            }));
+      },
+      ^bool {
+        return state_object_present;
+      },
+      false, base::TimeDelta::FromSeconds(10.0));
+  EXPECT_TRUE(state_object_present);

[Eugene But (OOO till 7-30), 2016/12/29 17:19:24]

No need for this line.

[kkhorimoto, 2017/01/24 05:22:54]

Done.

+}