Prerender: Add unit tests for mojo calls on PrerenderProcessor

Bug: 1149226
Change-Id: I48391f13e88a5cd772cb2bb79db01dcd54ea6285
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2549021Reviewed-by: Takashi Toyoshima <toyoshim@chromium.org>
Commit-Queue: Hiroki Nakagawa <nhiroki@chromium.org>
Cr-Commit-Position: refs/heads/master@{#829210}

content/browser/prerender/prerender_processor_unittest.cc

+// Copyright 2020 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 "content/browser/prerender/prerender_processor.h"
+
+#include "base/run_loop.h"
+#include "base/test/bind.h"
+#include "base/test/scoped_feature_list.h"
+#include "content/browser/site_instance_impl.h"
+#include "content/browser/storage_partition_impl.h"
+#include "content/public/browser/storage_partition.h"
+#include "content/public/test/test_browser_context.h"
+#include "content/test/test_render_view_host.h"
+#include "content/test/test_web_contents.h"
+#include "mojo/public/cpp/system/functions.h"
+#include "third_party/blink/public/common/features.h"
+
+namespace content {
+namespace {
+
+// TODO(https://crbug.com/839030): Remove this implementation along with
+// deprecating the prefixed prerender events.
+class PrerenderProcessorClient final
+    : public blink::mojom::PrerenderProcessorClient {
+ public:
+  // blink::mojom::PrerenderProcessorClient:
+  void OnPrerenderStart() override {}
+  void OnPrerenderStopLoading() override {}
+  void OnPrerenderDomContentLoaded() override {}
+  void OnPrerenderStop() override {}
+
+  mojo::PendingRemote<blink::mojom::PrerenderProcessorClient>
+  BindNewPipeAndPassRemote() {
+    return receiver_.BindNewPipeAndPassRemote();
+  }
+
+ private:
+  mojo::Receiver<blink::mojom::PrerenderProcessorClient> receiver_{this};
+};
+
+class PrerenderProcessorTest : public RenderViewHostImplTestHarness {
+ public:
+  void SetUp() override {
+    RenderViewHostImplTestHarness::SetUp();
+
+    scoped_feature_list_.InitAndEnableFeature(blink::features::kPrerender2);
+    browser_context_ = std::make_unique<TestBrowserContext>();
+
+    web_contents_ = TestWebContents::Create(
+        browser_context_.get(),
+        SiteInstanceImpl::Create(browser_context_.get()));
+    web_contents_->NavigateAndCommit(GURL("https://example.com"));
+  }
+
+  void TearDown() override {
+    web_contents_.reset();
+    browser_context_.reset();
+    RenderViewHostImplTestHarness::TearDown();
+  }
+
+  void DestroyPrerenderProcessors() {
+    // Resetting the web contents destroys render frame hosts, which in turn
+    // destroy `RenderFrameHostImpl::prerender_processor_receivers_`.
+    web_contents_.reset();
+  }
+
+  RenderFrameHostImpl* GetRenderFrameHost() {
+    DCHECK(web_contents_);
+    return web_contents_->GetMainFrame();
+  }
+
+  PrerenderHostRegistry* GetPrerenderHostRegistry() const {
+    return static_cast<StoragePartitionImpl*>(
+               BrowserContext::GetDefaultStoragePartition(
+                   browser_context_.get()))
+        ->GetPrerenderHostRegistry();
+  }
+
+ private:
+  base::test::ScopedFeatureList scoped_feature_list_;
+
+  std::unique_ptr<TestBrowserContext> browser_context_;
+  std::unique_ptr<TestWebContents> web_contents_;
+};
+
+TEST_F(PrerenderProcessorTest, StartCancel) {
+  RenderFrameHostImpl* render_frame_host = GetRenderFrameHost();
+  PrerenderHostRegistry* registry = GetPrerenderHostRegistry();
+
+  mojo::Remote<blink::mojom::PrerenderProcessor> remote;
+  render_frame_host->BindPrerenderProcessor(
+      render_frame_host, remote.BindNewPipeAndPassReceiver());
+
+  const GURL kPrerenderingUrl("https://example.com/next");
+  auto attributes = blink::mojom::PrerenderAttributes::New();
+  attributes->url = kPrerenderingUrl;
+  attributes->referrer = blink::mojom::Referrer::New();
+  PrerenderProcessorClient client;
+
+  // Start() call should register a new prerender host.
+  EXPECT_FALSE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+  remote->Start(std::move(attributes), client.BindNewPipeAndPassRemote());
+  remote.FlushForTesting();
+  EXPECT_TRUE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+
+  // Cancel() call should abandon the prerender host.
+  remote->Cancel();
+  remote.FlushForTesting();
+  EXPECT_FALSE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+}
+
+TEST_F(PrerenderProcessorTest, StartDisconnect) {
+  RenderFrameHostImpl* render_frame_host = GetRenderFrameHost();
+  PrerenderHostRegistry* registry = GetPrerenderHostRegistry();
+
+  mojo::Remote<blink::mojom::PrerenderProcessor> remote;
+  render_frame_host->BindPrerenderProcessor(
+      render_frame_host, remote.BindNewPipeAndPassReceiver());
+
+  const GURL kPrerenderingUrl("https://example.com/next");
+  auto attributes = blink::mojom::PrerenderAttributes::New();
+  attributes->url = kPrerenderingUrl;
+  attributes->referrer = blink::mojom::Referrer::New();
+  PrerenderProcessorClient client;
+
+  // Start() call should register a new prerender host.
+  EXPECT_FALSE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+  remote->Start(std::move(attributes), client.BindNewPipeAndPassRemote());
+  remote.FlushForTesting();
+  EXPECT_TRUE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+
+  // Connection lost should abandon the prerender host.
+  remote.reset();
+  // FlushForTesting() is no longer available. Instead, use base::RunLoop.
+  base::RunLoop().RunUntilIdle();
+  EXPECT_FALSE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+}
+
+TEST_F(PrerenderProcessorTest, CancelOnDestruction) {
+  RenderFrameHostImpl* render_frame_host = GetRenderFrameHost();
+  PrerenderHostRegistry* registry = GetPrerenderHostRegistry();
+
+  mojo::Remote<blink::mojom::PrerenderProcessor> remote;
+  render_frame_host->BindPrerenderProcessor(
+      render_frame_host, remote.BindNewPipeAndPassReceiver());
+
+  const GURL kPrerenderingUrl("https://example.com/next");
+  auto attributes = blink::mojom::PrerenderAttributes::New();
+  attributes->url = kPrerenderingUrl;
+  attributes->referrer = blink::mojom::Referrer::New();
+  PrerenderProcessorClient client;
+
+  // Start() call should register a new prerender host.
+  EXPECT_FALSE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+  remote->Start(std::move(attributes), client.BindNewPipeAndPassRemote());
+  remote.FlushForTesting();
+  EXPECT_TRUE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+
+  // The destructor of PrerenderProcessor should abandon the prerender host.
+  DestroyPrerenderProcessors();
+  EXPECT_FALSE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+}
+
+TEST_F(PrerenderProcessorTest, StartTwice) {
+  RenderFrameHostImpl* render_frame_host = GetRenderFrameHost();
+  PrerenderHostRegistry* registry = GetPrerenderHostRegistry();
+
+  mojo::Remote<blink::mojom::PrerenderProcessor> remote;
+  render_frame_host->BindPrerenderProcessor(
+      render_frame_host, remote.BindNewPipeAndPassReceiver());
+
+  // Set up the error handler for bad mojo messages.
+  std::string bad_message_error;
+  mojo::SetDefaultProcessErrorHandler(
+      base::BindLambdaForTesting([&](const std::string& error) {
+        EXPECT_TRUE(bad_message_error.empty());
+        bad_message_error = error;
+      }));
+
+  const GURL kPrerenderingUrl("https://example.com/next");
+  auto attributes1 = blink::mojom::PrerenderAttributes::New();
+  attributes1->url = kPrerenderingUrl;
+  attributes1->referrer = blink::mojom::Referrer::New();
+  PrerenderProcessorClient client1;
+
+  // Start() call should register a new prerender host.
+  EXPECT_FALSE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+  remote->Start(std::move(attributes1), client1.BindNewPipeAndPassRemote());
+  remote.FlushForTesting();
+  EXPECT_TRUE(registry->FindHostByUrlForTesting(kPrerenderingUrl));
+
+  auto attributes2 = blink::mojom::PrerenderAttributes::New();
+  attributes2->url = kPrerenderingUrl;
+  attributes2->referrer = blink::mojom::Referrer::New();
+  PrerenderProcessorClient client2;
+
+  // Call Start() again. This should be reported as a bad mojo message.
+  ASSERT_TRUE(bad_message_error.empty());
+  remote->Start(std::move(attributes2), client2.BindNewPipeAndPassRemote());
+  remote.FlushForTesting();
+  EXPECT_EQ(bad_message_error, "PP_START_TWICE");
+}
+
+TEST_F(PrerenderProcessorTest, CancelBeforeStart) {
+  RenderFrameHostImpl* render_frame_host = GetRenderFrameHost();
+
+  mojo::Remote<blink::mojom::PrerenderProcessor> remote;
+  render_frame_host->BindPrerenderProcessor(
+      render_frame_host, remote.BindNewPipeAndPassReceiver());
+
+  // Set up the error handler for bad mojo messages.
+  std::string bad_message_error;
+  mojo::SetDefaultProcessErrorHandler(
+      base::BindLambdaForTesting([&](const std::string& error) {
+        EXPECT_TRUE(bad_message_error.empty());
+        bad_message_error = error;
+      }));
+
+  const GURL kPrerenderingUrl("https://example.com/next");
+  auto attributes1 = blink::mojom::PrerenderAttributes::New();
+  attributes1->url = kPrerenderingUrl;
+  attributes1->referrer = blink::mojom::Referrer::New();
+  PrerenderProcessorClient client1;
+
+  // Call Cancel() before Start(). This should be reported as a bad mojo
+  // message.
+  ASSERT_TRUE(bad_message_error.empty());
+  remote->Cancel();
+  remote.FlushForTesting();
+  EXPECT_EQ(bad_message_error, "PP_CANCEL_BEFORE_START");
+}
+
+}  // namespace
+}  // namespace content

content/test/BUILD.gn

@@ -1889,6 +1889,7 @@ test("content_unittests") {
     "../browser/plugin_list_unittest.cc",
     "../browser/prerender/prerender_host_registry_unittest.cc",
     "../browser/prerender/prerender_host_unittest.cc",
+    "../browser/prerender/prerender_processor_unittest.cc",
     "../browser/presentation/presentation_service_impl_unittest.cc",
     "../browser/quota/quota_change_dispatcher_unittest.cc",
     "../browser/renderer_host/ancestor_throttle_unittest.cc",