Add some tests for ObservableListDecorator

Change-Id: I33b73ffae31972928697ca885d3e4445ca98bbc4
Reviewed-on: http://gerrit.dmdirc.com/2211
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Build Manager

src/com/dmdirc/util/ObservableListDecorator.java

@@ -191,8 +191,10 @@ public class ObservableListDecorator<T> implements ObservableList<T> {
 
         list.clear();
 
-        listeners.getCallable(ListObserver.class).onItemsRemoved(this, 0,
-                length - 1);
+        if (length > 0) {
+            listeners.getCallable(ListObserver.class).onItemsRemoved(this, 0,
+                    length - 1);
+        }
     }
 
     /** {@inheritDoc} */

test/com/dmdirc/util/ObservableListDecoratorTest.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2006-2011 DMDirc Developers
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.dmdirc.util;
+
+import java.util.Arrays;
+import java.util.List;
+import org.junit.Test;
+import java.util.LinkedList;
+
+import org.junit.Before;
+import static org.mockito.Mockito.*;
+
+public class ObservableListDecoratorTest {
+
+    private List<String> list;
+    private ObservableList<String> obslist;
+    private ListObserver observer;
+
+    @Before
+    public void setup() {
+        list = new LinkedList<String>();
+        obslist = new ObservableListDecorator<String>(list);
+        observer = mock(ListObserver.class);
+        obslist.addListListener(observer);
+    }
+
+    @Test
+    public void testAddingSingleEntryFiresListener() {
+        obslist.add("test");
+        verify(observer).onItemsAdded(obslist, 0, 0);
+        obslist.add("test");
+        verify(observer).onItemsAdded(obslist, 1, 1);
+    }
+
+    @Test
+    public void testAddingSingleEntryAtIndexFiresListener() {
+        list.addAll(Arrays.asList("one", "two", "three", "four"));
+        obslist.add(1, "one point five");
+        verify(observer).onItemsAdded(obslist, 1, 1);
+    }
+
+    @Test
+    public void testAddingRangeFiresListener() {
+        obslist.addAll(Arrays.asList("one", "two", "three", "four"));
+        verify(observer).onItemsAdded(obslist, 0, 3);
+        obslist.addAll(Arrays.asList("one", "two", "three", "four"));
+        verify(observer).onItemsAdded(obslist, 4, 7);
+    }
+
+    @Test
+    public void testAddingRangeAtIndexFiresListener() {
+        list.addAll(Arrays.asList("one", "two", "three", "four"));
+        obslist.addAll(1, Arrays.asList("one", "two", "three", "four"));
+        verify(observer).onItemsAdded(obslist, 1, 5);
+    }
+
+    @Test
+    public void testClearingFiresListener() {
+        list.addAll(Arrays.asList("one", "two", "three", "four"));
+        obslist.clear();
+        verify(observer).onItemsRemoved(obslist, 0, 3);
+    }
+
+    @Test
+    public void testClearingEmptyListDoesntFireListener() {
+        obslist.clear();
+        verify(observer, never()).onItemsRemoved(anyObject(), anyInt(), anyInt());
+    }
+
+    @Test
+    public void testRemovingByIndexFiresListener() {
+        list.addAll(Arrays.asList("one", "two", "three", "four"));
+        obslist.remove(2);
+        verify(observer).onItemsRemoved(obslist, 2, 2);
+    }
+
+    @Test
+    public void testRemovingByObjectFiresListener() {
+        list.addAll(Arrays.asList("one", "two", "three", "four"));
+        obslist.remove("three");
+        verify(observer).onItemsRemoved(obslist, 2, 2);
+    }
+
+}