views: support dialog width snapping once and for all

ui/views/bubble/bubble_frame_view_unittest.cc

 // 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 "ui/views/bubble/bubble_frame_view.h"
 
 #include <memory>
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "ui/gfx/geometry/insets.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/views/bubble/bubble_border.h"
+#include "ui/views/bubble/bubble_dialog_delegate.h"
 #include "ui/views/controls/button/label_button.h"
 #include "ui/views/test/test_views.h"
 #include "ui/views/test/views_test_base.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_delegate.h"
 
 namespace views {
 
 typedef ViewsTestBase BubbleFrameViewTest;
 
@@ skipping 456 matching lines @@
 #else
   maximum_rect.Inset(frame.bubble_border()->GetInsets());
 
   // Should ignore the contents view's maximum size and use the preferred size.
   gfx::Size expected_size(kPreferredClientWidth + kExpectedAdditionalWidth,
                           kPreferredClientHeight + kExpectedAdditionalHeight);
   EXPECT_EQ(expected_size, maximum_rect.size());
 #endif
 }
 
+namespace {
+
+class TestBubbleDialogDelegateView : public BubbleDialogDelegateView {
+ public:
+  TestBubbleDialogDelegateView()
+      : BubbleDialogDelegateView(nullptr, BubbleBorder::NONE) {
+    set_shadow(BubbleBorder::NO_ASSETS);
+    SetAnchorRect(gfx::Rect());
+  }
+  ~TestBubbleDialogDelegateView() override {}
+
+  // BubbleDialogDelegateView:
+  void DeleteDelegate() override {
+    // This delegate is owned by the test case itself, so it should not delete
+    // itself here.
+  }
+
+  int GetDialogButtons() const override { return ui::DIALOG_BUTTON_NONE; }
+
+  gfx::Size GetPreferredSize() const override { return gfx::Size(200, 200); }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestBubbleDialogDelegateView);
+};
+
+class TestLayoutProvider : public LayoutProvider {
+ public:
+  TestLayoutProvider() : LayoutProvider() {}
+  ~TestLayoutProvider() override {}
+
+  // LayoutProvider:
+  int GetSnappedDialogWidth(int min_width) const override {
+    return snap_to_ ? snap_to_ : min_width;
+  }
+
+  void set_snap_to(int width) { snap_to_ = width; }
+
+ private:
+  int snap_to_ = 0;
+
+  DISALLOW_COPY_AND_ASSIGN(TestLayoutProvider);
+};
+
+}  // namespace
+
+// This test ensures that if the installed LayoutProvider snaps dialog widths,
+// BubbleFrameView correctly sizes itself to that width.
+TEST_F(BubbleFrameViewTest, WidthSnaps) {
+  TestLayoutProvider provider;
+  TestBubbleDialogDelegateView delegate;
+
+  delegate.set_margins(gfx::Insets());
+
+  constexpr int kTestWidth = 300;

[Peter Kasting, 2017/04/24 23:06:31]

Nit: Declare as close as possible to first use (see
http://google.github.io/styleguide/cppguide.html#Local_Variables )

[Elly Fong-Jones, 2017/04/25 13:03:52]

Done.

+
+  Widget* w0 = BubbleDialogDelegateView::CreateBubble(&delegate);
+  w0->Show();
+  EXPECT_EQ(delegate.GetPreferredSize().width(),
+            w0->GetWindowBoundsInScreen().width());
+  w0->CloseNow();
+
+  provider.set_snap_to(kTestWidth);
+
+  // The Widget's snapped width should exactly match the width returned by the
+  // LayoutProvider.
+  Widget* w1 = BubbleDialogDelegateView::CreateBubble(&delegate);
+  w1->Show();
+  EXPECT_EQ(kTestWidth, w1->GetWindowBoundsInScreen().width());
+  w1->CloseNow();
+}
+
 }  // namespace views