Refactor the loading tracking logic in WebContentsImpl.

content/browser/web_contents/web_contents_impl_unittest.cc

Index: content/browser/web_contents/web_contents_impl_unittest.cc
diff --git a/content/browser/web_contents/web_contents_impl_unittest.cc b/content/browser/web_contents/web_contents_impl_unittest.cc
index da3c82e7d4826fe968344dadc907178eca8bb1d1..9f8e11ef8879bc6343e019add818143678c12df4 100644
--- a/content/browser/web_contents/web_contents_impl_unittest.cc
+++ b/content/browser/web_contents/web_contents_impl_unittest.cc
@@ -37,6 +37,7 @@
 #include "content/test/test_render_frame_host.h"
 #include "content/test/test_render_view_host.h"
 #include "content/test/test_web_contents.h"
+#include "net/base/load_flags.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace content {
@@ -2879,6 +2880,69 @@ TEST_F(WebContentsImplTest, StartStopEventsBalance) {
   EXPECT_FALSE(observer.is_loading());
 }
 
+// Ensure that WebContentsImpl does not stop loading too early when there still
+// is a pending renderer. This can happen if a same-process non user-initiated
+// navigation completes while there is an ongoing cross-process navigation.
+// TODO(fdegans): Rewrite the test for PlzNavigate when DidStartLoading and
+// DidStopLoading are properly called.
+TEST_F(WebContentsImplTest, NoEarlyStop) {
+  const GURL kUrl1("http://www.chromium.org");
+  const GURL kUrl2("http://www.google.com");
+  const GURL kUrl3("http://www.wikipedia.org");
+
+  contents()->NavigateAndCommit(kUrl1);
+
+  TestRenderFrameHost* current_rfh = contents()->GetMainFrame();
+
+  // Start a browser-initiated cross-process navigation to |kUrl2|. There should
+  // be a pending RenderFrameHost and the frame should be loading.

[Charlie Reis, 2015/03/03 06:32:23]

The comment says "the frame should be loading" but the code is checking whether
the WebContents is loading (same below).  Can we check the frame as well?

[Fabrice (no longer in Chrome), 2015/03/03 13:12:17]

We should not check the frame before the call to DidStartLoading because it
won't have started loading before then. I am changing the comment to state that
the WebContents should be loading instead.
I think checking the individual RFH status would be testing for implementation
rather than the flow in WebContents.

+  controller().LoadURL(
+      kUrl2, Referrer(), ui::PAGE_TRANSITION_TYPED, std::string());
+  EXPECT_TRUE(contents()->cross_navigation_pending());
+  TestRenderFrameHost* pending_rfh = contents()->GetPendingMainFrame();
+  ASSERT_NE(pending_rfh, nullptr);
+  EXPECT_TRUE(contents()->IsLoading());
+
+  // The current RenderFrameHost starts a non user-initiated render-initiated
+  // navigation and sends a DidStartLoading IPC. The frame should still be
+  // loading.
+  current_rfh->OnMessageReceived(
+    FrameHostMsg_DidStartLoading(current_rfh->GetRoutingID(), false));
+  EXPECT_TRUE(contents()->IsLoading());
+
+  // Simulate the pending RenderFrameHost DidStartLoading. There should still be
+  // a pending RenderFrameHost and the frame should still be loading.
+  pending_rfh->PrepareForCommit(kUrl2);
+  pending_rfh->OnMessageReceived(
+      FrameHostMsg_DidStartLoading(pending_rfh->GetRoutingID(), false));
+  EXPECT_EQ(contents()->GetPendingMainFrame(), pending_rfh);
+  EXPECT_TRUE(contents()->IsLoading());
+
+  // Simulate the current RenderFrameHost DidStopLoading. There should still be
+  // a pending RenderFrameHost and the frame should still be loading.
+  current_rfh->SendNavigate(1, kUrl3);
+  current_rfh->OnMessageReceived(
+      FrameHostMsg_DidStopLoading(current_rfh->GetRoutingID()));
+  EXPECT_EQ(contents()->GetPendingMainFrame(), pending_rfh);
+  EXPECT_TRUE(contents()->IsLoading());
+
+  // Commit the navigation, the formerly pending RenderFrameHost should now be
+  // the current RenderFrameHost and the frame should still be loading.
+  contents()->TestDidNavigate(pending_rfh, 1, kUrl2,
+                              ui::PAGE_TRANSITION_TYPED);
+  EXPECT_EQ(contents()->GetPendingMainFrame(), nullptr);
+  TestRenderFrameHost* new_current_rfh = contents()->GetMainFrame();
+  ASSERT_EQ(new_current_rfh, pending_rfh);
+  EXPECT_TRUE(contents()->IsLoading());
+
+  // Simulate the new current RenderFrameHost DidStopLoading. The frame should
+  // now have stopped loading.
+  new_current_rfh->OnMessageReceived(
+      FrameHostMsg_DidStopLoading(new_current_rfh->GetRoutingID()));
+  EXPECT_EQ(contents()->GetMainFrame(), new_current_rfh);
+  EXPECT_FALSE(contents()->IsLoading());
+}
+
 TEST_F(WebContentsImplTest, MediaPowerSaveBlocking) {
   // PlayerIDs are actually pointers cast to int64, so verify that both negative
   // and positive player ids don't blow up.