added drop(n) and dropWhile(predicates) for KT-2067 - also tail() now returns the usual idea of tail() - namely everything but the head - rather than just the last element. Finally added more test sample code to the kdoc

libraries/stdlib/test/CollectionTest.kt

@@ -302,6 +302,29 @@ class CollectionTest {
         }
     }
 
+    test fun drop() {
+        val coll = arrayList("foo", "bar", "abc")
+        assertEquals(arrayList("bar", "abc"), coll.drop(1))
+        assertEquals(arrayList("abc"), coll.drop(2))
+    }
+
+    test fun dropWhile() {
+        val coll = arrayList("foo", "bar", "abc")
+        assertEquals(arrayList("bar", "abc"), coll.dropWhile{ it.startsWith("f") })
+    }
+
+    test fun take() {
+        val coll = arrayList("foo", "bar", "abc")
+        assertEquals(arrayList("foo"), coll.take(1))
+        assertEquals(arrayList("foo", "bar"), coll.take(2))
+    }
+
+    test fun takeWhile() {
+        val coll = arrayList("foo", "bar", "abc")
+        assertEquals(arrayList("foo"), coll.takeWhile{ it.startsWith("f") })
+        assertEquals(arrayList("foo", "bar", "abc"), coll.takeWhile{ it.size == 3 })
+    }
+
     test fun toArray() {
         val data = arrayList("foo", "bar")
         val arr = data.toArray()

libraries/stdlib/test/ListTest.kt

@@ -1,36 +1,39 @@
 package test.collections
 
 import kotlin.test.*
-
-import org.junit.Test
+import org.junit.Test as test
 
 class ListTest {
-  val data = arrayList("foo", "bar")
 
-  Test fun headAndTail() {
-    val h = data.head
-    assertEquals("foo", h)
-
-    val t = data.tail
-    assertEquals("bar", t)
-  }
-
-  Test fun firstAndLast() {
-    val h = data.first
-    assertEquals("foo", h)
-
-    val t = data.last
-    assertEquals("bar", t)
-  }
-
-  Test fun withIndices() {
-    val withIndices = data.withIndices()
-    var index = 0
-    for (withIndex in withIndices) {
-      assertEquals(withIndex._1, index)
-      assertEquals(withIndex._2, data[index])
-      index++
+    test fun head() {
+        val data = arrayList("foo", "bar")
+        assertEquals("foo", data.head)
+    }
+
+    test fun tail() {
+        val data = arrayList("foo", "bar", "whatnot")
+        assertEquals(arrayList("bar", "whatnot"), data.tail)
+    }
+
+    test fun first() {
+        val data = arrayList("foo", "bar")
+        assertEquals("foo", data.first)
+    }
+
+    test fun last() {
+        val data = arrayList("foo", "bar")
+        assertEquals("bar", data.last)
+    }
+
+    test fun withIndices() {
+        val data = arrayList("foo", "bar")
+        val withIndices = data.withIndices()
+        var index = 0
+        for (withIndex in withIndices) {
+            assertEquals(withIndex._1, index)
+            assertEquals(withIndex._2, data[index])
+            index++
+        }
+        assertEquals(data.size(), index)
     }
-    assertEquals(data.size(), index)
-  }
 }