Add a TestBrowserDialog helper class for testing browser dialogs in a consistent way.

chrome/browser/ui/test/test_browser_dialog.cc

+// 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.
+
+#include "chrome/browser/ui/test/test_browser_dialog.h"
+
+#include "base/command_line.h"
+#include "base/message_loop/message_loop.h"
+#include "chrome/browser/platform_util.h"
+#include "ui/base/material_design/material_design_controller.h"
+#include "ui/base/test/material_design_controller_test_api.h"
+#include "ui/base/test/user_interactive_test_case.h"
+#include "ui/base/ui_base_switches.h"
+#include "ui/views/widget/widget.h"
+#include "ui/views/widget/widget_observer.h"
+
+namespace {
+
+// An automatic action for WidgetCloser to post to the RunLoop.
+// TODO(tapted): Explore asynchronous Widget::Close() and DialogClientView::
+// {Accept,Cancel}Window() approaches to test other dialog lifetimes.
+enum class DialogAction {
+  INTERACTIVE,  // Run interactively.
+  CLOSE_NOW,    // Call Widget::CloseNow().
+};
+
+// Helper to break out of the nested run loop that runs a test dialog.
+class WidgetCloser : public views::WidgetObserver {
+ public:
+  WidgetCloser(views::Widget* widget, DialogAction action)
+      : widget_(widget), weak_ptr_factory_(this) {
+    widget->AddObserver(this);
+    if (action == DialogAction::INTERACTIVE)
+      return;
+
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE,
+        base::Bind(&WidgetCloser::CloseNow, weak_ptr_factory_.GetWeakPtr()));
+  }
+
+  // WidgetObserver:
+  void OnWidgetDestroyed(views::Widget* widget) override {
+    widget_->RemoveObserver(this);
+    widget_ = nullptr;
+    base::MessageLoop::current()->QuitNow();
+  }
+
+ private:
+  void CloseNow() {
+    if (widget_)
+      widget_->CloseNow();
+  }
+
+  views::Widget* widget_;
+
+  base::WeakPtrFactory<WidgetCloser> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(WidgetCloser);
+};
+
+// Returns the test case portion of a --dialog= switch argument.
+std::string CaseFromDialogDescription(const std::string& argument) {
+  std::string::size_type dot = argument.find('.');
+  return dot == std::string::npos ? std::string() : argument.substr(dot + 1);
+}
+
+}  // namespace
+
+// static
+std::vector<std::string> TestDialogInterface::NameProvider() {
+  return {"Default"};
+}
+
+// static
+std::vector<std::string>& TestDialogInterface::GetDialogTestCases() {
+  CR_DEFINE_STATIC_LOCAL(std::vector<std::string>, all_cases, ());
+  return all_cases;
+}
+
+// static
+int TestDialogInterface::Register(const char* harness,
+                                  NameProviderFunction* name_provider) {
+  const std::string prefix = harness + std::string(".");
+  std::vector<std::string>& all_cases = GetDialogTestCases();
+  for (const std::string& name : name_provider())
+    all_cases.push_back(prefix + name);
+  return 1;
+}
+
+// static
+void TestDialogInterface::TestBrowserDialogRun(
+    TestDialogInterface* harness,
+    const std::vector<std::string>& available_cases) {
+  const base::CommandLine& command_line =
+      *base::CommandLine::ForCurrentProcess();
+
+#if defined(OS_MACOSX)
+  // The rest of this method assumes the child dialog is toolkit-views. So, for
+  // Mac, it will only work if --secondary-ui-md is passed. Without this, a
+  // Cocoa dialog will be created, which TestDialogInterface doesn't support.
+  // Force SecondaryUiMaterial() on Mac to get coverage on the bots. Leave it
+  // optional elsewhere so that the non-MD dialog can be invoked to compare.
+  ui::test::MaterialDesignControllerTestAPI md_test_api(
+      ui::MaterialDesignController::GetMode());
+  md_test_api.SetSecondaryUiMaterial(true);
+#endif
+
+  int dialog_index = 0;
+  std::string dialog_name =
+      command_line.GetSwitchValueASCII(internal::kDialogSwitch);
+  if (!dialog_name.empty()) {
+    const std::string case_name = CaseFromDialogDescription(dialog_name);
+    auto it =
+        std::find(available_cases.begin(), available_cases.end(), case_name);
+    ASSERT_NE(it, available_cases.end());
+    dialog_index = std::distance(available_cases.begin(), it);
+  }
+
+  gfx::NativeView parent =
+      platform_util::GetViewForWindow(harness->DialogParent());
+  views::Widget::Widgets widgets_before;
+  views::Widget::GetAllChildWidgets(parent, &widgets_before);
+
+  harness->ShowDialog(dialog_index);
+  views::Widget::Widgets widgets_after;
+  views::Widget::GetAllChildWidgets(parent, &widgets_after);
+
+  auto added = base::STLSetDifference<std::vector<views::Widget*>>(
+      widgets_after, widgets_before);
+
+  // This can fail if no dialog was shown, if the dialog shown wasn't a toolkit-
+  // views dialog, or if more than one child dialog was shown.
+  ASSERT_EQ(1u, added.size());
+
+  const DialogAction action =
+      command_line.HasSwitch(internal::kInteractiveSwitch)
+          ? DialogAction::INTERACTIVE
+          : DialogAction::CLOSE_NOW;
+
+  WidgetCloser closer(added[0], action);
+  ::test::RunTestInteractively();
+}