Add support for the dropRight().

Author: javadev

lodash-plugin/src/main/java/com/github/underscore/lodash/$.java

@@ -54,6 +54,14 @@ public Chain<List<T>> drop() {
         public Chain<List<T>> drop(final Integer n) {
             return new Chain<List<T>>($.drop(value(), n));
         }
+
+        public Chain<List<T>> dropRight() {
+            return new Chain<List<T>>($.dropRight(value()));
+        }
+
+        public Chain<List<T>> dropRight(final Integer n) {
+            return new Chain<List<T>>($.dropRight(value(), n));
+        }
     }
 
     public static Chain chain(final String item) {
@@ -72,12 +80,12 @@ public static <T> Chain chain(final T ... list) {
         return new $.Chain<T>(Arrays.asList(list));
     }
 
-    public static <T> List<List<T>> chunk(final Iterable<T> list, final Integer size) {
+    public static <T> List<List<T>> chunk(final Iterable<T> iterable, final Integer size) {
         int index = 0;
-        int length = size(list);
+        int length = size(iterable);
         final List<List<T>> result = new ArrayList<List<T>>(length / size);
         while (index < length) {
-            result.add(newArrayList(list).subList(index, Math.min(length, index + size)));
+            result.add(newArrayList(iterable).subList(index, Math.min(length, index + size)));
             index += size;
         }
         return result;
@@ -87,22 +95,38 @@ public List<List<T>> chunk(final Integer size) {
         return chunk(getIterable(), size);
     }
 
-    public static <T> List<T> drop(final Iterable<T> list) {
-        return rest(newArrayList(list));
+    public static <T> List<T> drop(final Iterable<T> iterable) {
+        return rest(newArrayList(iterable));
     }
 
     public List<T> drop() {
         return drop(getIterable());
     }
 
-    public static <T> List<T> drop(final Iterable<T> list, final Integer n) {
-        return rest(newArrayList(list), n);
+    public static <T> List<T> drop(final Iterable<T> iterable, final Integer n) {
+        return rest(newArrayList(iterable), n);
     }
 
     public List<T> drop(final Integer n) {
         return drop(getIterable(), n);
     }
 
+    public static <T> List<T> dropRight(final Iterable<T> iterable) {
+        return initial(newArrayList(iterable));
+    }
+
+    public List<T> dropRight() {
+        return dropRight(getIterable());
+    }
+
+    public static <T> List<T> dropRight(final Iterable<T> iterable, final Integer n) {
+        return initial(newArrayList(iterable), n);
+    }
+
+    public List<T> dropRight(final Integer n) {
+        return dropRight(getIterable(), n);
+    }
+
     public static void main(String ... args) {
         final String message = "Underscore-java-lodash is a lodash plugin for underscore-java.\n\n"
             + "For docs, license, tests, and downloads, see: http://javadev.github.io/underscore-java";

lodash-plugin/src/test/java/com/github/underscore/lodash/LodashTest.java

@@ -75,6 +75,31 @@ public void drop() {
         assertEquals("[1, 2, 3]", $.drop(asList(1, 2, 3), 0).toString());
     }
 
+/*
+_.dropRight([1, 2, 3]);
+// → [1, 2]
+
+_.dropRight([1, 2, 3], 2);
+// → [1]
+
+_.dropRight([1, 2, 3], 5);
+// → []
+
+_.dropRight([1, 2, 3], 0);
+// → [1, 2, 3]
+*/
+    @Test
+    public void dropRight() {
+        assertEquals("[1, 2]", $.dropRight(asList(1, 2, 3)).toString());
+        assertEquals("[1, 2]", new $(asList(1, 2, 3)).dropRight().toString());
+        assertEquals("[1, 2]", $.chain(asList(1, 2, 3)).dropRight().toString());
+        assertEquals("[1]", $.dropRight(asList(1, 2, 3), 2).toString());
+        assertEquals("[1]", new $(asList(1, 2, 3)).dropRight(2).toString());
+        assertEquals("[1]", $.chain(asList(1, 2, 3)).dropRight(2).toString());
+        assertEquals("[]", $.dropRight(asList(1, 2, 3), 5).toString());
+        assertEquals("[1, 2, 3]", $.dropRight(asList(1, 2, 3), 0).toString());
+    }
+
     @Test
     public void main() {
         $.main(new String[] {});

src/main/java/com/github/underscore/$.java

@@ -621,7 +621,7 @@ public static <E> List<E> initial(final List<E> list) {
     }
 
     public static <E> List<E> initial(final List<E> list, final int n) {
-        return list.subList(0, list.size() - n);
+        return list.subList(0, Math.max(0, list.size() - n));
     }
 
     public static <E> E[] initial(final E[] array) {