Add test for invoking WebUI tab strip context menu

This is the first C++-side browser test for the thumbstrip.

Bug: 997887
Change-Id: Ic155adc5c2d519cc383438326c7ffb6fe21caf1b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1861110
Commit-Queue: Collin Baker <collinbaker@chromium.org>
Reviewed-by: John Lee <johntlee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#706102}

chrome/browser/ui/webui/tab_strip/tab_strip_ui_browsertest.cc

+// Copyright 2019 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 "chrome/browser/ui/webui/tab_strip/tab_strip_ui.h"
+
+#include <memory>
+
+#include "base/json/json_reader.h"
+#include "base/json/json_writer.h"
+#include "base/test/scoped_feature_list.h"
+#include "base/values.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/ui_features.h"
+#include "chrome/common/chrome_isolated_world_ids.h"
+#include "chrome/common/webui_url_constants.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "content/public/browser/navigation_controller.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/test/browser_test_utils.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "ui/base/models/menu_model.h"
+#include "ui/gfx/geometry/point.h"
+#include "ui/gfx/geometry/point_conversions.h"
+#include "ui/gfx/geometry/point_f.h"
+#include "ui/gfx/geometry/rect_f.h"
+
+namespace {
+
+class MockTabStripUIEmbedder : public TabStripUI::Embedder {
+ public:
+  MOCK_METHOD(void,
+              ShowContextMenuAtPoint,
+              (gfx::Point point, std::unique_ptr<ui::MenuModel> menu_model),
+              (override));
+};
+
+}  // namespace
+
+class TabStripUIBrowserTest : public InProcessBrowserTest {
+ public:
+  void SetUp() override {
+    // In this test, we create our own TabStripUI instance with a mock
+    // Embedder. Disable the production one to avoid conflicting with
+    // it.
+    feature_override_.InitAndDisableFeature(features::kWebUITabStrip);
+    InProcessBrowserTest::SetUp();
+  }
+
+  void TearDown() override {
+    InProcessBrowserTest::TearDown();
+    feature_override_.Reset();
+  }
+
+  void SetUpOnMainThread() override {
+    webui_contents_ = content::WebContents::Create(
+        content::WebContents::CreateParams(browser()->profile()));
+
+    // Start loading WebUI, injecting our TabStripUI::Embedder immediately
+    // after.
+    webui_contents_->GetController().LoadURLWithParams(
+        content::NavigationController::LoadURLParams(
+            GURL(chrome::kChromeUITabStripURL)));
+    TabStripUI* const tab_strip_ui =
+        static_cast<TabStripUI*>(webui_contents_->GetWebUI()->GetController());
+    tab_strip_ui->Initialize(browser(), &mock_embedder_);
+
+    // Finish loading after initializing TabStripUI.
+    ASSERT_TRUE(content::WaitForLoadStop(webui_contents_.get()));
+  }
+
+  void TearDownOnMainThread() override { webui_contents_.reset(); }
+
+ protected:
+  ::testing::NiceMock<MockTabStripUIEmbedder> mock_embedder_;
+  std::unique_ptr<content::WebContents> webui_contents_;
+
+ private:
+  base::test::ScopedFeatureList feature_override_;
+};
+
+// Checks that the contextmenu event on a tab gets forwarded to the
+// TabStripUI::Embedder.
+IN_PROC_BROWSER_TEST_F(TabStripUIBrowserTest,
+                       InvokesEmbedderContextMenuForTab) {
+  using ::testing::_;
+
+  const std::string invoke_menu_js =
+      "const event ="
+      "    new MouseEvent('contextmenu', { clientX: 100, clientY: 50 });"
+      "document.querySelector('tabstrip-tab-list')"
+      "    .shadowRoot.querySelector('tabstrip-tab')"
+      "    .dispatchEvent(event)";
+
+  EXPECT_CALL(mock_embedder_, ShowContextMenuAtPoint(gfx::Point(100, 50), _))
+      .Times(1);
+  ASSERT_TRUE(content::ExecJs(webui_contents_.get(), invoke_menu_js,
+                              content::EXECUTE_SCRIPT_DEFAULT_OPTIONS,
+                              ISOLATED_WORLD_ID_CHROME_INTERNAL));
+}

chrome/test/BUILD.gn

@@ -2665,6 +2665,10 @@ if (!is_android) {
       sources +=
           [ "../browser/net/trial_comparison_cert_verifier_browsertest.cc" ]
     }
+
+    if (enable_webui_tab_strip) {
+      sources += [ "../browser/ui/webui/tab_strip/tab_strip_ui_browsertest.cc" ]
+    }
   }
 }