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 {}
+
+  // DialogDelegateView:

[tapted, 2017/04/21 00:20:31]

// BubbleDialogDelegateView:

peter has a preference to name the "visible" base class on the list of parents
on the class declaration. (I used to go for "ancestor where these are declared"
since that's where the "missing" documentation should be - which would be 3
blocks here: WidgetDelegate/DialogDelegate/View). But DialogDelegateView is none
of these :)

[Elly Fong-Jones, 2017/04/21 15:47:54]

Okay, changed to 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;
+
+  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