githubsheng
diff --git a/‎__tests__/List.ts
Lines changed: 18 additions & 0 deletions b/‎__tests__/List.ts
Lines changed: 18 additions & 0 deletions
diff --git a/‎dist/immutable.js
Lines changed: 4 additions & 4 deletions b/‎dist/immutable.js
Lines changed: 4 additions & 4 deletions
@@ -457,6 +457,24 @@ describe('List', () => {
     expect(r.toArray()).toEqual(['c', 'd']);
   });
 
+  it('takes and skips no-ops return same reference', () => {
+    var v = List.of('a', 'b', 'c', 'd', 'e', 'f');
+    var r = v.skip(0).take(6);
+    expect(r).toBe(v);
+  });
+
+  it('takeLast and skipLast values', () => {
+    var v = List.of('a', 'b', 'c', 'd', 'e', 'f');
+    var r = v.skipLast(1).takeLast(2);
+    expect(r.toArray()).toEqual(['d', 'e']);
+  });
+
+  it('takeLast and skipLast no-ops return same reference', () => {
+    var v = List.of('a', 'b', 'c', 'd', 'e', 'f');
+    var r = v.skipLast(0).takeLast(6);
+    expect(r).toBe(v);
+  });
+
   it('efficiently chains array methods', () => {
     var v = List.of(1,2,3,4,5,6,7,8,9,10,11,12,13,14);
 
 
@@ -3557,7 +3557,7 @@
   // #pragma Helper Functions
 
   function reify(iter, seq) {
-    return isSeq(iter) ? seq : iter.constructor(seq);
+    return iter === seq ? iter : isSeq(iter) ? seq : iter.constructor(seq);
   }
 
   function validateEntry(entry) {
@@ -4611,11 +4611,11 @@
     },
 
     skip: function(amount) {
-      return this.slice(Math.max(0, amount));
+      return amount === 0 ? this : this.slice(Math.max(0, amount));
     },
 
     skipLast: function(amount) {
-      return reify(this, this.toSeq().reverse().skip(amount).reverse());
+      return amount === 0 ? this : this.slice(0, -Math.max(0, amount));
     },
 
     skipWhile: function(predicate, context) {
@@ -4635,7 +4635,7 @@
     },
 
     takeLast: function(amount) {
-      return reify(this, this.toSeq().reverse().take(amount).reverse());
+      return this.slice(-Math.max(0, amount));
     },
 
     takeWhile: function(predicate, context) {