Fix prerender histograms for multiple prerender case.

chrome/browser/prerender/prerender_manager_unittest.cc

Index: chrome/browser/prerender/prerender_manager_unittest.cc
diff --git a/chrome/browser/prerender/prerender_manager_unittest.cc b/chrome/browser/prerender/prerender_manager_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..86d6f33f444435e9bbe3de5d2259796c088f20dd
--- /dev/null
+++ b/chrome/browser/prerender/prerender_manager_unittest.cc
@@ -0,0 +1,100 @@
+// Copyright (c) 2012 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.
+
+#include "base/message_loop.h"
+#include "chrome/browser/prerender/prerender_manager.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "content/public/test/test_browser_thread.h"
+
+
+namespace prerender {
+
+namespace {
+
+// These tests don't require the dummy PrerenderContents & PrerenderManager that
+// the heavier PrerenderTest.* tests do.
+class PrerenderManagerTest : public testing::Test {
+ public:
+  PrerenderManagerTest()
+      : ui_thread_(content::BrowserThread::UI, &message_loop_),
+        prerender_manager_(NULL, NULL) {
+  }
+
+  PrerenderManager* prerender_manager() { return &prerender_manager_; }
+
+  MessageLoop message_loop_;
+  content::TestBrowserThread ui_thread_;
+  PrerenderManager prerender_manager_;
+};
+
+TEST_F(PrerenderManagerTest, IsWebContentsPrerenderedTest) {
+  // The methods being tested should not dereference their WebContents, instead
+  // they use it as a unique identifier.
+  int not_a_webcontents = 0;
+  content::WebContents* web_contents =
+      reinterpret_cast<content::WebContents*>(&not_a_webcontents);
+
+  EXPECT_FALSE(prerender_manager()->IsWebContentsPrerendered(
+      web_contents, NULL));
+
+  const Origin origin = ORIGIN_OMNIBOX;
+  prerender_manager()->MarkWebContentsAsPrerendered(web_contents, origin);
+
+  Origin test_origin = ORIGIN_NONE;
+  EXPECT_TRUE(prerender_manager()->IsWebContentsPrerendered(
+      web_contents, &test_origin));
+
+  int also_not_a_webcontents = 1;
+  content::WebContents* another_web_contents =
+      reinterpret_cast<content::WebContents*>(&also_not_a_webcontents);
+  EXPECT_FALSE(prerender_manager()->IsWebContentsPrerendered(
+      another_web_contents, NULL));
+
+  EXPECT_EQ(origin, test_origin);
+
+  prerender_manager()->MarkWebContentsAsNotPrerendered(web_contents);
+  EXPECT_FALSE(prerender_manager()->IsWebContentsPrerendered(
+      web_contents, NULL));
+}
+
+TEST_F(PrerenderManagerTest, WouldWebContentsBePrerenderedTest) {
+  // The methods being tested should not dereference their WebContents, instead
+  // they use it as a unique identifier.
+  int not_a_webcontents = 0;
+  content::WebContents* web_contents =
+      reinterpret_cast<content::WebContents*>(&not_a_webcontents);
+
+  EXPECT_FALSE(prerender_manager()->WouldWebContentsBePrerendered(
+      web_contents, NULL));
+
+  const Origin origin = ORIGIN_OMNIBOX;
+  prerender_manager()->MarkWebContentsAsWouldBePrerendered(web_contents,
+                                                           origin);
+
+  Origin test_origin = ORIGIN_NONE;
+  EXPECT_TRUE(prerender_manager()->WouldWebContentsBePrerendered(
+      web_contents, &test_origin));
+  EXPECT_EQ(origin, test_origin);
+
+  int also_not_a_webcontents = 1;
+  content::WebContents* another_web_contents =
+      reinterpret_cast<content::WebContents*>(&also_not_a_webcontents);
+  EXPECT_FALSE(prerender_manager()->WouldWebContentsBePrerendered(
+      another_web_contents, NULL));
+
+  // Control group (aka WouldBe...) web_contents need to be removed twice. See
+  // the comment in prerender_manager.cc at the definition of
+  // WouldBePrerenderedWebContentsData and its inner enum State.
+  prerender_manager()->MarkWebContentsAsNotPrerendered(web_contents);
+  EXPECT_TRUE(prerender_manager()->WouldWebContentsBePrerendered(
+      web_contents, NULL));
+
+  prerender_manager()->MarkWebContentsAsNotPrerendered(web_contents);
+  EXPECT_FALSE(prerender_manager()->WouldWebContentsBePrerendered(
+      web_contents, NULL));
+}
+
+}  // namespace
+
+}  // namespace prerender