Make resizing a window by snapping it left or right take into account the window's minimum width

ash/wm/workspace/snap_sizer_unittest.cc

+// Copyright 2013 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 "ash/wm/workspace/snap_sizer.h"
+
+#include "ash/screen_ash.h"
+#include "ash/shell.h"
+#include "ash/test/ash_test_base.h"
+#include "ash/wm/window_util.h"
+#include "ui/aura/root_window.h"
+#include "ui/aura/test/test_window_delegate.h"
+#include "ui/aura/window.h"
+#include "ui/gfx/screen.h"
+
+namespace ash {
+
+typedef test::AshTestBase SnapSizerTest;
+
+using internal::SnapSizer;
+
+// Test that a window gets properly snapped to the display's edges in a
+// multi monitor environment.
+TEST_F(SnapSizerTest, MultipleDisplays) {
+  if (!SupportsMultipleDisplays())
+    return;
+
+  UpdateDisplay("0+0-500x400, 0+500-600x400");
+  const gfx::Rect kPrimaryDisplayWorkAreaBounds =
+      ash::Shell::GetScreen()->GetPrimaryDisplay().work_area();
+  const gfx::Rect kSecondaryDisplayWorkAreaBounds =
+      ScreenAsh::GetSecondaryDisplay().work_area();
+
+  scoped_ptr<aura::Window> window(
+      CreateTestWindowInShellWithBounds(gfx::Rect(100, 100, 100, 100)));
+
+  SnapSizer::SnapWindow(window.get(), SnapSizer::LEFT_EDGE);
+  gfx::Rect expected = gfx::Rect(
+      kPrimaryDisplayWorkAreaBounds.x(),
+      kPrimaryDisplayWorkAreaBounds.y(),
+      window->bounds().width(), // No expectation for the width.
+      kPrimaryDisplayWorkAreaBounds.height());
+  EXPECT_EQ(expected.ToString(), window->GetBoundsInScreen().ToString());
+
+  SnapSizer::SnapWindow(window.get(), SnapSizer::RIGHT_EDGE);
+  // The width should not change when a window switches from being snapped to
+  // the left edge to being snapped to the right edge.
+  expected.set_x(kPrimaryDisplayWorkAreaBounds.right() - expected.width());
+  EXPECT_EQ(expected.ToString(), window->GetBoundsInScreen().ToString());
+
+  // Move the window to the secondary display.
+  window->SetBoundsInScreen(gfx::Rect(600, 0, 100, 100),
+                            ScreenAsh::GetSecondaryDisplay());
+
+  SnapSizer::SnapWindow(window.get(), SnapSizer::RIGHT_EDGE);
+  expected = gfx::Rect(
+      kSecondaryDisplayWorkAreaBounds.right() - window->bounds().width(),
+      kSecondaryDisplayWorkAreaBounds.y(),
+      window->bounds().width(),  // No expectation for the width.
+      kSecondaryDisplayWorkAreaBounds.height());
+  EXPECT_EQ(expected.ToString(), window->GetBoundsInScreen().ToString());
+
+  SnapSizer::SnapWindow(window.get(), SnapSizer::LEFT_EDGE);
+  // The width should not change when a window switches from being snapped to
+  // the right edge to being snapped to the left edge.
+  expected.set_x(kSecondaryDisplayWorkAreaBounds.x());
+  EXPECT_EQ(expected.ToString(), window->GetBoundsInScreen().ToString());
+}
+
+// Test how the minimum and maximum size specified by the aura::WindowDelegate
+// affect snapping.
+TEST_F(SnapSizerTest, MinimumSize) {
+  if (!SupportsHostWindowResize())
+    return;
+
+  UpdateDisplay("0+0-600x800");
+  const gfx::Rect kWorkAreaBounds =
+      ash::Shell::GetScreen()->GetPrimaryDisplay().work_area();
+
+  aura::test::TestWindowDelegate delegate;
+  scoped_ptr<aura::Window> window(CreateTestWindowInShellWithDelegate(
+      &delegate, -1, gfx::Rect(0, 100, kWorkAreaBounds.width() - 1, 100)));
+
+  // It should be possible to snap a window with a minimum size.
+  delegate.set_minimum_size(gfx::Size(kWorkAreaBounds.width() - 1, 0));
+  EXPECT_TRUE(ash::wm::CanSnapWindow(window.get()));
+  SnapSizer::SnapWindow(window.get(), SnapSizer::RIGHT_EDGE);
+  gfx::Rect expected = gfx::Rect(kWorkAreaBounds.x() + 1,
+                                 kWorkAreaBounds.y(),
+                                 kWorkAreaBounds.width() - 1,
+                                 kWorkAreaBounds.height());
+  EXPECT_EQ(expected.ToString(), window->GetBoundsInScreen().ToString());
+
+  // It should not be possible to snap a window with a maximum size.
+  delegate.set_minimum_size(gfx::Size());
+  delegate.set_maximum_size(gfx::Size(kWorkAreaBounds.width() - 1, INT_MAX));
+  EXPECT_FALSE(ash::wm::CanSnapWindow(window.get()));
+}
+
+}  // namespace ash