Created test verifying setting the state object via replaceState()

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"

[Eugene But (OOO till 7-30), 2016/12/29 17:12:59]

s/import/include

[kkhorimoto, 2017/01/24 04:57:15]

Done.

 #include "base/strings/utf_string_conversions.h"
 #include "base/test/ios/wait_util.h"
+#import "ios/web/navigation/navigation_item_impl.h"
 #include "ios/web/public/navigation_item.h"
 #include "ios/web/public/navigation_manager.h"
 #import "ios/web/public/test/http_server.h"
 #include "ios/web/public/test/http_server_util.h"
 #import "ios/web/public/test/web_view_interaction_test_util.h"
 #include "ios/web/public/web_state/web_state.h"
 #include "ios/web/public/web_state/web_state_observer.h"
 #import "ios/web/test/web_int_test.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/gtest_mac.h"
@@ skipping 268 matching lines @@
   __block bool title_updated = false;
   base::test::ios::WaitUntilCondition(^bool {
     title_updated = current_item()->GetTitle() == ASCIIToUTF16(new_title);
     return title_updated;
   });
   EXPECT_TRUE(title_updated);
   // Verify that the forward navigation was not pruned.
   EXPECT_EQ(GetIndexOfNavigationItem(current_item()) + 1,
             GetIndexOfNavigationItem(about_blank_item));
 }
+
+// Tests that calling window.history.replaceState() with a new state object
+// replaces the state object for the current NavigationItem.
+TEST_F(HistoryStateOperationsTest, StateReplacement) {
+  // 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);
+  web::NavigationItem* about_blank_item = current_item();
+  ExpectPageLoad(state_operations_url());
+  navigation_manager()->GoBack();
+  WaitForPageToLoad();
+  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 17:12:59]

std::string empty_title;

[kkhorimoto, 2017/01/24 04:57:15]

Done.

+  GURL empty_url("");

[Eugene But (OOO till 7-30), 2016/12/29 17:12:59]

GURL empty_url;

[kkhorimoto, 2017/01/24 04:57:15]

Done.

+  SetStateParams(new_state, empty_title, empty_url);
+  ASSERT_TRUE(web::test::TapWebViewElementWithId(web_state(), kReplaceStateID));
+  // Verify that the state is reflected in the latest NavigationItem.
+  std::string serialized_state("\"STATE OBJECT\"");
+  __block bool state_updated = false;
+  base::test::ios::WaitUntilCondition(^bool {
+    web::NavigationItemImpl* item =
+        static_cast<web::NavigationItemImpl*>(current_item());
+    std::string item_state =
+        base::SysNSStringToUTF8(item->GetSerializedStateObject());

[Eugene But (OOO till 7-30), 2016/12/29 17:12:59]

Is there a way to avoid using implementation details?

[kkhorimoto, 2017/01/24 04:57:15]

Not really.  NavigationEntry doesn't expose the state object, so it's better for
us to also keep it contained to the implementation file.  I've also added a
check for the actual state object returned by JavaScript, but it'd be better to
check the NavigationItem state as well.

+    state_updated = item_state == serialized_state;

[Eugene But (OOO till 7-30), 2016/12/29 17:13:00]

return item_state == serialized_state;

[kkhorimoto, 2017/01/24 04:57:15]

Done.

+    return state_updated;
+  });
+  EXPECT_TRUE(state_updated);

[Eugene But (OOO till 7-30), 2016/12/29 17:13:00]

There is no need for this check.

[kkhorimoto, 2017/01/24 04:57:15]

Done.

+  // Verify that the forward navigation was not pruned.
+  EXPECT_EQ(GetIndexOfNavigationItem(current_item()) + 1,
+            GetIndexOfNavigationItem(about_blank_item));
+}