Add a ListModel::Move.

ui/base/models/list_model_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/base/models/list_model.h"
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 10 matching lines @@
   int id_;
   DISALLOW_COPY_AND_ASSIGN(FooItem);
 };
 
 class ListModelTest : public testing::Test,
                       public ListModelObserver {
  public:
   ListModelTest()
       : added_count_(0),
         removed_count_(0),
+        moved_count_(0),
         changed_count_(0) {
   }
 
   void ExpectCountsEqual(size_t added_count,
                          size_t removed_count,
+                         size_t moved_count,
                          size_t changed_count) {
     EXPECT_EQ(added_count, added_count_);
     EXPECT_EQ(removed_count, removed_count_);
+    EXPECT_EQ(moved_count, moved_count_);
     EXPECT_EQ(changed_count, changed_count_);
   }
 
   void ClearCounts() {
-    added_count_ = removed_count_ = changed_count_ = 0;
+    added_count_ = removed_count_ = moved_count_ = changed_count_ = 0;
   }
 
   // ListModelObserver implementation:
   virtual void ListItemsAdded(size_t start, size_t count) OVERRIDE {
     added_count_ += count;
   }
   virtual void ListItemsRemoved(size_t start, size_t count) OVERRIDE {
     removed_count_ += count;
   }
+  virtual void ListItemMoved(size_t index, size_t target_index) OVERRIDE {
+    ++moved_count_;
+  }
   virtual void ListItemsChanged(size_t start, size_t count) OVERRIDE {
     changed_count_ += count;
   }
 
  private:
   size_t added_count_;
   size_t removed_count_;
+  size_t moved_count_;
   size_t changed_count_;
 
   DISALLOW_COPY_AND_ASSIGN(ListModelTest);
 };
 
 TEST_F(ListModelTest, Add) {
   ListModel<FooItem> model;
   model.AddObserver(this);
 
   // Append FooItem(0)
   model.Add(new FooItem(0));
-  ExpectCountsEqual(1, 0, 0);
+  ExpectCountsEqual(1, 0, 0, 0);
 
   // Append FooItem(1)
   model.Add(new FooItem(1));
-  ExpectCountsEqual(2, 0, 0);
+  ExpectCountsEqual(2, 0, 0, 0);
 
   // Insert FooItem(2) at position 0
   model.AddAt(0, new FooItem(2));
-  ExpectCountsEqual(3, 0, 0);
+  ExpectCountsEqual(3, 0, 0, 0);
 
-  // Total 3 items in mode.
+  // Total 3 items in model.
   EXPECT_EQ(3U, model.item_count());
 
   // First one should be FooItem(2), followed by FooItem(0) and FooItem(1)
   EXPECT_EQ(2, model.GetItemAt(0)->id());
   EXPECT_EQ(0, model.GetItemAt(1)->id());
   EXPECT_EQ(1, model.GetItemAt(2)->id());
 }
 
 TEST_F(ListModelTest, Remove) {
   ListModel<FooItem> model;
   model.AddObserver(this);
 
   model.Add(new FooItem(0));
   model.Add(new FooItem(1));
   model.Add(new FooItem(2));
 
   ClearCounts();
 
   // Remove item at index 1 from model and release memory.
   model.DeleteAt(1);
-  ExpectCountsEqual(0, 1, 0);
+  ExpectCountsEqual(0, 1, 0, 0);
 
   EXPECT_EQ(2U, model.item_count());
   EXPECT_EQ(0, model.GetItemAt(0)->id());
   EXPECT_EQ(2, model.GetItemAt(1)->id());
 
   // Remove all items from model and delete them.
   model.DeleteAll();
-  ExpectCountsEqual(0, 3, 0);
+  ExpectCountsEqual(0, 3, 0, 0);
 }
 
 TEST_F(ListModelTest, RemoveAll) {
   ListModel<FooItem> model;
   model.AddObserver(this);
 
   scoped_ptr<FooItem> foo0(new FooItem(0));
   scoped_ptr<FooItem> foo1(new FooItem(1));
   scoped_ptr<FooItem> foo2(new FooItem(2));
 
   model.Add(foo0.get());
   model.Add(foo1.get());
   model.Add(foo2.get());
 
   ClearCounts();
 
   // Remove all items and scoped_ptr above would release memory.
   model.RemoveAll();
-  ExpectCountsEqual(0, 3, 0);
+  ExpectCountsEqual(0, 3, 0, 0);
+}
+
+TEST_F(ListModelTest, Move) {
+  ListModel<FooItem> model;
+  model.AddObserver(this);
+
+  model.Add(new FooItem(0));
+  model.Add(new FooItem(1));
+  model.Add(new FooItem(2));
+
+  ClearCounts();
+
+  // Moves item at index 0 to index 2.
+  model.Move(0, 2);
+  ExpectCountsEqual(0, 0, 1, 0);
+  EXPECT_EQ(1, model.GetItemAt(0)->id());
+  EXPECT_EQ(2, model.GetItemAt(1)->id());
+  EXPECT_EQ(0, model.GetItemAt(2)->id());
 }
 
 TEST_F(ListModelTest, FakeUpdate) {
   ListModel<FooItem> model;
   model.AddObserver(this);
 
   model.Add(new FooItem(0));
   model.Add(new FooItem(1));
   model.Add(new FooItem(2));
 
   ClearCounts();
 
   model.NotifyItemsChanged(0, 1);
-  ExpectCountsEqual(0, 0, 1);
+  ExpectCountsEqual(0, 0, 0, 1);
 
   model.NotifyItemsChanged(1, 2);
-  ExpectCountsEqual(0, 0, 3);
+  ExpectCountsEqual(0, 0, 0, 3);
 }
 
 }  // namespace ui