diff --git a/test/_helper.js b/test/_helper.js
index a988f30d73..8273a11443 100644
--- a/test/_helper.js
+++ b/test/_helper.js
@@ -1,5 +1,6 @@
-var fs = require("fs");
-var _  = require("lodash");
+var path = require("path");
+var fs   = require("fs");
+var _    = require("lodash");
 
 var humanise = function (val) {
   return val.replace(/-/g, " ");
@@ -37,7 +38,6 @@ exports.get = function (entryName) {
 
     _.each(fs.readdirSync(suite.filename), function (taskName) {
       var taskDir = suite.filename + "/" + taskName;
-      if (fs.statSync(taskDir).isFile()) return;
 
       var actualLocAlias = suiteName + "/" + taskName + "/actual.js";
       var expectLocAlias = suiteName + "/" + taskName + "/expected.js";
@@ -47,6 +47,13 @@ exports.get = function (entryName) {
       var expectLoc = taskDir + "/expected.js";
       var execLoc   = taskDir + "/exec.js";
 
+      if (fs.statSync(taskDir).isFile()) {
+        var ext = path.extname(taskDir);
+        if (ext === ".json") return;
+
+        execLoc = taskDir;
+      }
+
       var taskOpts = _.merge({
         filenameRelative: expectLocAlias,
         sourceFileName:   actualLocAlias,
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/arguments-refers-to-parent-function.js b/test/fixtures/transformation/esnext-es6-arrow-functions/arguments-refers-to-parent-function.js
new file mode 100644
index 0000000000..d299fb5379
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/arguments-refers-to-parent-function.js
@@ -0,0 +1,57 @@
+function makeMultiplier() {
+  // `arguments` should refer to `makeMultiplier`'s arguments.
+  return (n) => [].slice.call(arguments).reduce((a, b) => a * b) * n;
+}
+
+function toArray() {
+  // Intentionally nest arrow functions to ensure `arguments` is put inside
+  // `toArray`'s scope.
+  return (() => (arguments, (() => [].slice.call(arguments)).call())).call();
+}
+
+function returnDotArguments(object) {
+  // Ensure `arguments` is not treated as a reference to the magic value.
+  return (() => object.arguments).call();
+}
+
+function returnArgumentsObject() {
+  // Ensure `arguments` is not treated as a reference to the magic value.
+  return (() => ({arguments: 1})).call();
+}
+
+function makeArgumentsReturner() {
+  return (() => function() {
+    return [].slice.call(arguments);
+  }).call();
+}
+
+// i.e. 2 * 3 * 4 == 24, not 16 (4 * 4)
+assert.equal(
+  makeMultiplier(2, 3)(4),
+  24,
+  'ensure `arguments` is hoisted out to the first non-arrow scope'
+);
+
+assert.deepEqual(
+  toArray(1, 2, 3),
+  [1, 2, 3],
+  'ensure `arguments` is hoisted out to the first non-arrow scope'
+);
+
+assert.equal(
+  returnDotArguments({arguments: 1}),
+  1,
+  'member accesses with `arguments` property should not be replaced'
+);
+
+assert.deepEqual(
+  returnArgumentsObject(),
+  {arguments: 1},
+  'object property keys named `arguments` should not be replaced'
+);
+
+assert.deepEqual(
+  makeArgumentsReturner()(1, 2, 3),
+  [1, 2, 3],
+  'arguments should not be hoisted from inside non-arrow functions'
+);
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/does-not-bind-this-from-standard-function.js b/test/fixtures/transformation/esnext-es6-arrow-functions/does-not-bind-this-from-standard-function.js
new file mode 100644
index 0000000000..c2eeddcc3e
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/does-not-bind-this-from-standard-function.js
@@ -0,0 +1,5 @@
+var dynamicThisGetter = () => function(){ return this; };
+assert.equal(
+  normalize('('+dynamicThisGetter.toString()+')'),
+  normalize('(function(){ return function(){ return this; }; })')
+);
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/empty-arrow-function.js b/test/fixtures/transformation/esnext-es6-arrow-functions/empty-arrow-function.js
new file mode 100644
index 0000000000..0b95435853
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/empty-arrow-function.js
@@ -0,0 +1,2 @@
+var empty = () => {};
+assert.equal(empty(), undefined);
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/handles-nested-context-bindings.js b/test/fixtures/transformation/esnext-es6-arrow-functions/handles-nested-context-bindings.js
new file mode 100644
index 0000000000..03041f0297
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/handles-nested-context-bindings.js
@@ -0,0 +1,12 @@
+var obj = {
+  method: function() {
+    return () => (this, () => this);
+  },
+
+  method2: function() {
+    return () => () => this;
+  }
+};
+
+assert.strictEqual(obj.method()()(), obj);
+assert.strictEqual(obj.method2()()(), obj);
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/no-parens-for-low-precedence-expression-body.js b/test/fixtures/transformation/esnext-es6-arrow-functions/no-parens-for-low-precedence-expression-body.js
new file mode 100644
index 0000000000..66fad996e5
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/no-parens-for-low-precedence-expression-body.js
@@ -0,0 +1,2 @@
+var square = x => x * x;
+assert.equal(square(4), 16);
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/object-literal-needs-parens.js b/test/fixtures/transformation/esnext-es6-arrow-functions/object-literal-needs-parens.js
new file mode 100644
index 0000000000..3ec553b180
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/object-literal-needs-parens.js
@@ -0,0 +1,2 @@
+var keyMaker = val => ({ key: val });
+assert.deepEqual(keyMaker(9), { key: 9 });
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/only-lexical-this-not-dynamic-this.js b/test/fixtures/transformation/esnext-es6-arrow-functions/only-lexical-this-not-dynamic-this.js
new file mode 100644
index 0000000000..68f68c14dc
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/only-lexical-this-not-dynamic-this.js
@@ -0,0 +1,7 @@
+var obj = {
+  method: function() {
+    return () => this;
+  }
+};
+
+assert.strictEqual(obj.method()(), obj);
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/passed-to-function.js b/test/fixtures/transformation/esnext-es6-arrow-functions/passed-to-function.js
new file mode 100644
index 0000000000..75fbefbacd
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/passed-to-function.js
@@ -0,0 +1,2 @@
+var odds = [0, 2, 4].map(v => v + 1);
+assert.deepEqual(odds, [1, 3, 5]);
diff --git a/test/fixtures/transformation/esnext-es6-arrow-functions/single-param-does-not-need-parens.js b/test/fixtures/transformation/esnext-es6-arrow-functions/single-param-does-not-need-parens.js
new file mode 100644
index 0000000000..c2b56e7bbc
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-arrow-functions/single-param-does-not-need-parens.js
@@ -0,0 +1,2 @@
+var identity = x => x;
+assert.equal(identity(1), 1);
diff --git a/test/fixtures/transformation/esnext-es6-classes/anonymous-class.js b/test/fixtures/transformation/esnext-es6-classes/anonymous-class.js
new file mode 100644
index 0000000000..231ba49b9e
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/anonymous-class.js
@@ -0,0 +1,29 @@
+var Animal = class {
+  sayHi() {
+    return 'Hi, I am a '+this.type()+'.';
+  }
+
+  static getName() {
+    return 'Animal';
+  }
+};
+
+var Dog = class extends Animal {
+  type() { return 'dog'; }
+
+  sayHi() {
+    return super() + ' WOOF!';
+  }
+
+  static getName() {
+    return super() + '/Dog';
+  }
+};
+
+assert.equal(new Dog().sayHi(), 'Hi, I am a dog. WOOF!');
+assert.equal(Dog.getName(), 'Animal/Dog');
+
+var count = 0;
+var Cat = class extends (function(){ count++; return Animal; })() {};
+
+assert.equal(count, 1);
diff --git a/test/fixtures/transformation/esnext-es6-classes/call-super-function.js b/test/fixtures/transformation/esnext-es6-classes/call-super-function.js
new file mode 100644
index 0000000000..5c7efe0dc6
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/call-super-function.js
@@ -0,0 +1,21 @@
+class Animal {
+  sayHi() {
+    return 'I am an animal.'
+  }
+
+  sayOther() {
+    return 'WAT?!';
+  }
+}
+
+class Horse extends Animal {
+  sayHi() {
+    return super.sayOther();
+  }
+
+  sayOther() {
+    return 'I see dead objects.';
+  }
+}
+
+assert.equal(new Horse().sayHi(), 'WAT?!');
diff --git a/test/fixtures/transformation/esnext-es6-classes/class-expressions.js b/test/fixtures/transformation/esnext-es6-classes/class-expressions.js
new file mode 100644
index 0000000000..1c2bb96a80
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/class-expressions.js
@@ -0,0 +1,9 @@
+var Person = (class Person {});
+assert.equal(typeof Person, 'function');
+
+assert.equal(
+  (function(){ return (class Person {}); })().name,
+  'Person'
+);
+
+assert.equal(typeof (class {}), 'function');
diff --git a/test/fixtures/transformation/esnext-es6-classes/class-extend.js b/test/fixtures/transformation/esnext-es6-classes/class-extend.js
new file mode 100644
index 0000000000..56035dd0b6
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/class-extend.js
@@ -0,0 +1,15 @@
+class Animal {
+  sayHi() {
+    return 'Hi, I am a '+this.type()+'.';
+  }
+}
+
+class Dog extends Animal {
+  type() { return 'dog'; }
+
+  sayHi() {
+    return super() + ' WOOF!';
+  }
+}
+
+assert.equal(new Dog().sayHi(), 'Hi, I am a dog. WOOF!');
diff --git a/test/fixtures/transformation/esnext-es6-classes/class-with-constructor.js b/test/fixtures/transformation/esnext-es6-classes/class-with-constructor.js
new file mode 100644
index 0000000000..4dcf3296f0
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/class-with-constructor.js
@@ -0,0 +1,14 @@
+class Multiplier {
+  constructor(n=1) {
+    this.n = n;
+  }
+
+  multiply(n=1) {
+    return n * this.n;
+  }
+}
+
+assert.equal(new Multiplier().n, 1);
+assert.equal(new Multiplier(6).n, 6);
+assert.equal(new Multiplier().multiply(), 1);
+assert.equal(new Multiplier(2).multiply(3), 6);
diff --git a/test/fixtures/transformation/esnext-es6-classes/class-with-method-declaration.js b/test/fixtures/transformation/esnext-es6-classes/class-with-method-declaration.js
new file mode 100644
index 0000000000..f8d9d7a207
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/class-with-method-declaration.js
@@ -0,0 +1,10 @@
+class Person {
+  getName() {
+    return this.firstName + ' ' + this.lastName;
+  }
+}
+
+var me = new Person();
+me.firstName = 'Brian';
+me.lastName = 'Donovan';
+assert.equal(me.getName(), 'Brian Donovan');
diff --git a/test/fixtures/transformation/esnext-es6-classes/empty-named-class.js b/test/fixtures/transformation/esnext-es6-classes/empty-named-class.js
new file mode 100644
index 0000000000..602a6702d3
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/empty-named-class.js
@@ -0,0 +1,5 @@
+class Foo {
+}
+
+assert.equal(new Foo().constructor, Foo, 'Foo instances should have Foo as constructor');
+assert.ok(new Foo() instanceof Foo, 'Foo instances should be `instanceof` Foo');
diff --git a/test/fixtures/transformation/esnext-es6-classes/enumerable.js b/test/fixtures/transformation/esnext-es6-classes/enumerable.js
new file mode 100644
index 0000000000..fe5c02d113
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/enumerable.js
@@ -0,0 +1,20 @@
+class Point {
+  constructor(x, y) {
+    this.x = x;
+    this.y = y;
+  }
+
+  toString() {
+    return '(' + this.x + ', ' + this.y + ')';
+  }
+}
+
+var point = new Point(1, 2);
+var keys = [];
+
+for (var key in point) {
+  keys.push(key);
+}
+
+assert.equal(point.toString(), '(1, 2)');
+assert.deepEqual(keys.sort(), ['x', 'y']);
diff --git a/test/fixtures/transformation/esnext-es6-classes/explicit-super-in-constructor.js b/test/fixtures/transformation/esnext-es6-classes/explicit-super-in-constructor.js
new file mode 100644
index 0000000000..d30f21cba5
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/explicit-super-in-constructor.js
@@ -0,0 +1,15 @@
+class Point {
+  constructor(x, y) {
+    this.x = x;
+    this.y = y;
+  }
+}
+
+class ZeroPoint extends Point {
+  constructor() {
+    super(0, 0);
+  }
+}
+
+assert.equal(new ZeroPoint().x, 0);
+assert.equal(new ZeroPoint().y, 0);
diff --git a/test/fixtures/transformation/esnext-es6-classes/extends-null.js b/test/fixtures/transformation/esnext-es6-classes/extends-null.js
new file mode 100644
index 0000000000..fa3821d8c7
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/extends-null.js
@@ -0,0 +1,4 @@
+class Obj extends null {}
+
+assert.strictEqual(Obj.toString, Function.toString);
+assert.strictEqual(new Obj().toString, undefined);
diff --git a/test/fixtures/transformation/esnext-es6-classes/getter-setter-super.js b/test/fixtures/transformation/esnext-es6-classes/getter-setter-super.js
new file mode 100644
index 0000000000..98d7bc0eea
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/getter-setter-super.js
@@ -0,0 +1,15 @@
+class Animal {
+  get sound() {
+    return 'I am a ' + this.type + '.';
+  }
+}
+
+class Cat extends Animal {
+  get type() { return 'cat'; }
+
+  get sound() {
+    return super.sound + ' MEOW!';
+  }
+}
+
+assert.equal(new Cat().sound, 'I am a cat. MEOW!');
diff --git a/test/fixtures/transformation/esnext-es6-classes/getter-setter.js b/test/fixtures/transformation/esnext-es6-classes/getter-setter.js
new file mode 100644
index 0000000000..8f9519f9ba
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/getter-setter.js
@@ -0,0 +1,28 @@
+class Person {
+  constructor(firstName, lastName) {
+    this.firstName = firstName;
+    this.lastName = lastName;
+  }
+
+  get name() {
+    return this.firstName + ' ' + this.lastName;
+  }
+
+  set name(name) {
+    var parts = name.split(' ');
+    this.firstName = parts[0];
+    this.lastName = parts[1];
+  }
+}
+
+var mazer = new Person('Mazer', 'Rackham');
+assert.equal(mazer.name, 'Mazer Rackham');
+mazer.name = 'Ender Wiggin';
+assert.equal(mazer.firstName, 'Ender');
+assert.equal(mazer.lastName, 'Wiggin');
+
+var forLoopProperties = [];
+for (var key in mazer) {
+  forLoopProperties.push(key);
+}
+assert.ok(forLoopProperties.indexOf('name') >= 0, 'getters/setters are enumerable');
diff --git a/test/fixtures/transformation/esnext-es6-classes/implicit-superclass.js b/test/fixtures/transformation/esnext-es6-classes/implicit-superclass.js
new file mode 100644
index 0000000000..96755df101
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/implicit-superclass.js
@@ -0,0 +1,9 @@
+class Obj {
+  constructor() {
+    super();
+  }
+}
+
+assert.doesNotThrow(function() {
+  new Obj();
+});
diff --git a/test/fixtures/transformation/esnext-es6-classes/method-declaration-with-arguments.js b/test/fixtures/transformation/esnext-es6-classes/method-declaration-with-arguments.js
new file mode 100644
index 0000000000..b70c56e68c
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/method-declaration-with-arguments.js
@@ -0,0 +1,7 @@
+class Tripler {
+  triple(n) {
+    return n * 3;
+  }
+}
+
+assert.equal(new Tripler().triple(2), 6);
diff --git a/test/fixtures/transformation/esnext-es6-classes/methods-are-writable.js b/test/fixtures/transformation/esnext-es6-classes/methods-are-writable.js
new file mode 100644
index 0000000000..19ffd5aa73
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/methods-are-writable.js
@@ -0,0 +1,12 @@
+var value;
+
+class Foo {
+  foo() {
+    value = 1;
+  }
+}
+
+var foo = new Foo();
+foo.foo = function() { value = 2; };
+foo.foo();
+assert.equal(value, 2);
diff --git a/test/fixtures/transformation/esnext-es6-classes/methods-with-rest-params.js b/test/fixtures/transformation/esnext-es6-classes/methods-with-rest-params.js
new file mode 100644
index 0000000000..77b7bb0774
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/methods-with-rest-params.js
@@ -0,0 +1,28 @@
+class Joiner {
+  constructor(string) {
+    this.string = string;
+  }
+
+  join(...items) {
+    return items.join(this.string);
+  }
+
+  static join(string, ...items) {
+    var joiner = new this(string);
+    // TODO: use spread params here
+    return joiner.join.apply(joiner, items);
+  }
+}
+
+class ArrayLike {
+  constructor(...items) {
+    items.forEach(function(item, i) {
+      this[i] = item;
+    }.bind(this));
+    this.length = items.length;
+  }
+}
+
+var joiner = new Joiner(' & ');
+assert.equal(joiner.join(4, 5, 6), '4 & 5 & 6');
+assert.equal(new ArrayLike('a', 'b')[1], 'b');
diff --git a/test/fixtures/transformation/esnext-es6-classes/static-getter.js b/test/fixtures/transformation/esnext-es6-classes/static-getter.js
new file mode 100644
index 0000000000..af9fe0afe6
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/static-getter.js
@@ -0,0 +1,12 @@
+class Point {
+  constructor(x, y) {
+    this.x = x;
+    this.y = y;
+  }
+
+  static get ORIGIN() {
+    return new this(0, 0);
+  }
+}
+
+assert.deepEqual(Point.ORIGIN, new Point(0, 0));
\ No newline at end of file
diff --git a/test/fixtures/transformation/esnext-es6-classes/static-method.js b/test/fixtures/transformation/esnext-es6-classes/static-method.js
new file mode 100644
index 0000000000..564fb13c5b
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/static-method.js
@@ -0,0 +1,30 @@
+class Tripler {
+  static triple(n=1) {
+    return n * 3;
+  }
+
+  static toString() {
+    return '3' + super() + '3';
+  }
+}
+
+class MegaTripler extends Tripler {
+  static triple(n=1) {
+    return super(n) * super(n);
+  }
+}
+
+var tripler = new Tripler();
+
+assert.equal(Tripler.triple(), 3);
+assert.equal(Tripler.triple(2), 6);
+assert.equal(tripler.triple, undefined);
+
+assert.equal(Tripler.toString(), '3' + Object.toString.call(Tripler) + '3');
+
+var mega = new MegaTripler();
+
+assert.equal(MegaTripler.triple(2), 36);
+assert.equal(mega.triple, undefined);
+
+assert.equal(MegaTripler.toString(), '3' + Object.toString.call(MegaTripler) + '3');
diff --git a/test/fixtures/transformation/esnext-es6-classes/static-setter.js b/test/fixtures/transformation/esnext-es6-classes/static-setter.js
new file mode 100644
index 0000000000..08fae30af5
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/static-setter.js
@@ -0,0 +1,7 @@
+class Person {
+  static set DB(value) {
+    assert.equal(value, 'mysql');
+  }
+}
+
+Person.DB = 'mysql';
diff --git a/test/fixtures/transformation/esnext-es6-classes/strict-mode.js b/test/fixtures/transformation/esnext-es6-classes/strict-mode.js
new file mode 100644
index 0000000000..d3ece2608e
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/strict-mode.js
@@ -0,0 +1,23 @@
+class StrictModeTest {
+  test() {
+    var implicitThisInsideClassBody = (function() {
+      return this;
+    })();
+    assert.strictEqual(
+      implicitThisInsideClassBody,
+      undefined,
+      'implicit `this` inside class body is undefined'
+    );
+  }
+}
+
+new StrictModeTest().test();
+
+var implicitThisOutsideClass = (function() {
+  return this;
+})();
+assert.notStrictEqual(
+  implicitThisOutsideClass,
+  undefined,
+  'implicit `this` outside class body is not undefined'
+);
diff --git a/test/fixtures/transformation/esnext-es6-classes/super-change-proto.js b/test/fixtures/transformation/esnext-es6-classes/super-change-proto.js
new file mode 100644
index 0000000000..d0012cfc0b
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-classes/super-change-proto.js
@@ -0,0 +1,20 @@
+var log = '';
+
+class Base {
+  p() { log += '[Base]'; }
+}
+
+class OtherBase {
+  p() { log += '[OtherBase]'; }
+}
+class Derived extends Base {
+  p() {
+    log += '[Derived]';
+    super();
+    Derived.prototype.__proto__ = OtherBase.prototype;
+    super();
+  }
+}
+
+new Derived().p();
+assert.equal(log, '[Derived][Base][OtherBase]');
diff --git a/test/fixtures/transformation/esnext-es6-computed-properties/accessor.js b/test/fixtures/transformation/esnext-es6-computed-properties/accessor.js
new file mode 100644
index 0000000000..bedcb7785a
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-computed-properties/accessor.js
@@ -0,0 +1,8 @@
+var x = 'y';
+
+var foo = {
+  get [x]() { return this._y; },
+  set [x](v) { this._y = v; }
+};
+
+assert.equal((foo.y = 10, foo.y), 10);
diff --git a/test/fixtures/transformation/esnext-es6-computed-properties/method.js b/test/fixtures/transformation/esnext-es6-computed-properties/method.js
new file mode 100644
index 0000000000..e28e4d18d5
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-computed-properties/method.js
@@ -0,0 +1,3 @@
+var x = 'y';
+assert.equal({[x]: function() { return 10; }}.y(), 10);
+assert.equal({[x + 'y']() { return 10; }}.yy(), 10);
diff --git a/test/fixtures/transformation/esnext-es6-computed-properties/nested.js b/test/fixtures/transformation/esnext-es6-computed-properties/nested.js
new file mode 100644
index 0000000000..ea11b2c6f6
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-computed-properties/nested.js
@@ -0,0 +1,4 @@
+var x = 'y';
+var foo = {[x]: 10, z: {[x]: 10}};
+assert.equal(foo.y + foo.z.y, 20);
+assert.equal({[x]: {[x]: {[x]: 10}}}.y.y.y, 10);
diff --git a/test/fixtures/transformation/esnext-es6-computed-properties/simple.js b/test/fixtures/transformation/esnext-es6-computed-properties/simple.js
new file mode 100644
index 0000000000..21e56afe58
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-computed-properties/simple.js
@@ -0,0 +1,3 @@
+var x = 'y';
+assert.equal({[x]: 10}.y, 10);
+assert.equal({[x + 'y']: 10}.yy, 10);
diff --git a/test/fixtures/transformation/esnext-es6-default-parameters/arity.js b/test/fixtures/transformation/esnext-es6-default-parameters/arity.js
new file mode 100644
index 0000000000..030f3e08ea
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-default-parameters/arity.js
@@ -0,0 +1,3 @@
+assert.equal((function(a){}).length, 1);
+assert.equal((function(a=5){}).length, 0);
+assert.equal((function(a, b, c=5){}).length, 2);
diff --git a/test/fixtures/transformation/esnext-es6-default-parameters/arrow-function.js b/test/fixtures/transformation/esnext-es6-default-parameters/arrow-function.js
new file mode 100644
index 0000000000..66c0068d94
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-default-parameters/arrow-function.js
@@ -0,0 +1,8 @@
+function makeMultiplier(x=1) {
+  return (y=1) => x * y;
+}
+
+assert.equal(makeMultiplier()(), 1);
+assert.equal(makeMultiplier(2)(3), 6);
+assert.deepEqual([1, 2, 3].map(makeMultiplier(2)), [2, 4, 6]);
+assert.deepEqual([undefined, null, 0].map(makeMultiplier(2)), [2, 0, 0]);
diff --git a/test/fixtures/transformation/esnext-es6-default-parameters/null-vs-undefined.js b/test/fixtures/transformation/esnext-es6-default-parameters/null-vs-undefined.js
new file mode 100644
index 0000000000..b028ba3e09
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-default-parameters/null-vs-undefined.js
@@ -0,0 +1,5 @@
+function foo(x=5, y=6) {
+  return [x, y];
+}
+
+assert.deepEqual(foo(undefined, null), [5, null]);
diff --git a/test/fixtures/transformation/esnext-es6-default-parameters/scope.js b/test/fixtures/transformation/esnext-es6-default-parameters/scope.js
new file mode 100644
index 0000000000..54848cd8f2
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-default-parameters/scope.js
@@ -0,0 +1,11 @@
+function call(fn, context=this) {
+  return fn.call(context);
+}
+
+var context = {a: 99};
+
+// use the default parameter
+assert.strictEqual(call.call(context, function(){ return this.a; }), 99);
+
+// explicitly provide the default parameter value
+assert.strictEqual(call(function(){ return this.a; }, context), 99);
diff --git a/test/fixtures/transformation/esnext-es6-default-parameters/simple-function.js b/test/fixtures/transformation/esnext-es6-default-parameters/simple-function.js
new file mode 100644
index 0000000000..d7bf1bfa1c
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-default-parameters/simple-function.js
@@ -0,0 +1,4 @@
+function foo(x=5) {
+  return x;
+}
+assert.equal(foo(), 5);
diff --git a/test/fixtures/transformation/esnext-es6-object-concise/method-arguments.js b/test/fixtures/transformation/esnext-es6-object-concise/method-arguments.js
new file mode 100644
index 0000000000..392586fc9b
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-object-concise/method-arguments.js
@@ -0,0 +1,7 @@
+var a = {
+  echo(c) {
+    return c;
+  }
+};
+
+assert.strictEqual(a.echo(1), 1);
diff --git a/test/fixtures/transformation/esnext-es6-object-concise/method-context.js b/test/fixtures/transformation/esnext-es6-object-concise/method-context.js
new file mode 100644
index 0000000000..53c4bf3bc7
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-object-concise/method-context.js
@@ -0,0 +1,9 @@
+var a = {
+  b() {
+    return this;
+  }
+};
+
+var context = {};
+assert.strictEqual(a.b(), a);
+assert.strictEqual(a.b.call(context), context);
\ No newline at end of file
diff --git a/test/fixtures/transformation/esnext-es6-object-concise/method-has-name.js b/test/fixtures/transformation/esnext-es6-object-concise/method-has-name.js
new file mode 100644
index 0000000000..320ec33b54
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-object-concise/method-has-name.js
@@ -0,0 +1,7 @@
+var a = {
+  b() {
+    return 'c';
+  }
+};
+
+assert.equal(a.b.name, 'b');
diff --git a/test/fixtures/transformation/esnext-es6-object-concise/method-is-not-in-scope-inside.js b/test/fixtures/transformation/esnext-es6-object-concise/method-is-not-in-scope-inside.js
new file mode 100644
index 0000000000..4f58980df0
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-object-concise/method-is-not-in-scope-inside.js
@@ -0,0 +1,9 @@
+var b = 1;
+
+var a = {
+  b() {
+    return b;
+  }
+};
+
+assert.equal(a.b(), 1);
diff --git a/test/fixtures/transformation/esnext-es6-object-concise/method-to-string.js b/test/fixtures/transformation/esnext-es6-object-concise/method-to-string.js
new file mode 100644
index 0000000000..ba3f86cb78
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-object-concise/method-to-string.js
@@ -0,0 +1,10 @@
+var a = {
+  b() {
+    return b;
+  }
+};
+
+assert.ok(
+  /return b/.test(a.b.toString()),
+  'toString contains body'
+);
\ No newline at end of file
diff --git a/test/fixtures/transformation/esnext-es6-object-concise/method.js b/test/fixtures/transformation/esnext-es6-object-concise/method.js
new file mode 100644
index 0000000000..1707a7aebb
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-object-concise/method.js
@@ -0,0 +1,7 @@
+var a = {
+  b() {
+    return 'c';
+  }
+};
+
+assert.equal(a.b(), 'c');
diff --git a/test/fixtures/transformation/esnext-es6-rest-parameters/arrow-fn.js b/test/fixtures/transformation/esnext-es6-rest-parameters/arrow-fn.js
new file mode 100644
index 0000000000..34c96f5ecb
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-rest-parameters/arrow-fn.js
@@ -0,0 +1,8 @@
+/* jshint esnext: true */
+/* global expect */
+
+var join = (joinStr, ...items) => {
+  return items.join(joinStr);
+};
+
+expect(join(' ', 'a', 'b', 'c')).to.equal('a b c');
diff --git a/test/fixtures/transformation/esnext-es6-rest-parameters/declaration.js b/test/fixtures/transformation/esnext-es6-rest-parameters/declaration.js
new file mode 100644
index 0000000000..1cc45ac46f
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-rest-parameters/declaration.js
@@ -0,0 +1,8 @@
+/* jshint esnext: true */
+/* global expect */
+
+function join(joinStr, ...items) {
+  return items.join(joinStr);
+}
+
+expect(join(' ', 'a', 'b', 'c')).to.equal('a b c');
diff --git a/test/fixtures/transformation/esnext-es6-rest-parameters/rest.js b/test/fixtures/transformation/esnext-es6-rest-parameters/rest.js
new file mode 100644
index 0000000000..9d0e63e85d
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-rest-parameters/rest.js
@@ -0,0 +1,8 @@
+/* jshint esnext: true */
+/* global expect */
+
+var join = function(joinStr, ...items) {
+  return items.join(joinStr);
+};
+
+expect(join(' ', 'a', 'b', 'c')).to.equal('a b c');
diff --git a/test/fixtures/transformation/esnext-es6-spread/arguments-as-array.js b/test/fixtures/transformation/esnext-es6-spread/arguments-as-array.js
new file mode 100644
index 0000000000..d0957e35b4
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/arguments-as-array.js
@@ -0,0 +1,6 @@
+function arrayOf() {
+  return [...arguments];
+}
+
+assert.equal(Object.prototype.toString.call(arrayOf()), '[object Array]');
+assert.deepEqual(arrayOf(1, 2, 3), [1, 2, 3]);
diff --git a/test/fixtures/transformation/esnext-es6-spread/array-literal.js b/test/fixtures/transformation/esnext-es6-spread/array-literal.js
new file mode 100644
index 0000000000..3c1bea826f
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/array-literal.js
@@ -0,0 +1,3 @@
+var names = ['Brian', 'Madeline'];
+assert.deepEqual(['Thomas', ...names], ['Thomas', 'Brian', 'Madeline']);
+assert.deepEqual([1, 2, ...[3, 4, 5]], [1, 2, 3, 4, 5]);
diff --git a/test/fixtures/transformation/esnext-es6-spread/call-with-array-literal.js b/test/fixtures/transformation/esnext-es6-spread/call-with-array-literal.js
new file mode 100644
index 0000000000..19cffabc6d
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/call-with-array-literal.js
@@ -0,0 +1,5 @@
+function sum(...numbers) {
+  return numbers.reduce(function(sum, n) { return n + sum; }, 0);
+}
+
+assert.equal(sum(4, 5, ...[10, 20, 30]), 69);
diff --git a/test/fixtures/transformation/esnext-es6-spread/inside-function-expression.js b/test/fixtures/transformation/esnext-es6-spread/inside-function-expression.js
new file mode 100644
index 0000000000..c2c06da399
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/inside-function-expression.js
@@ -0,0 +1,10 @@
+var object = {
+  list: [],
+
+  append: function(...items) {
+    this.list.push(...items);
+  }
+};
+
+object.append(1, 2, ...[3, 4]);
+assert.deepEqual(object.list, [1, 2, 3, 4]);
diff --git a/test/fixtures/transformation/esnext-es6-spread/iterator.js b/test/fixtures/transformation/esnext-es6-spread/iterator.js
new file mode 100644
index 0000000000..438e7564de
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/iterator.js
@@ -0,0 +1,19 @@
+function Symbol() {}
+Symbol.iterator = '@@iterator';
+
+var obj = {
+  '@@iterator': function() {
+    var ttl = 3;
+    return {
+      next: function() {
+        if (ttl === 0) {
+          return { done: true, value: null };
+        } else {
+          return { done: false, value: ttl-- };
+        }
+      }
+    };
+  }
+};
+
+assert.deepEqual([3, 2, 1], [...obj]);
diff --git a/test/fixtures/transformation/esnext-es6-spread/new-object.js b/test/fixtures/transformation/esnext-es6-spread/new-object.js
new file mode 100644
index 0000000000..6e4af74279
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/new-object.js
@@ -0,0 +1,11 @@
+var callCount = 0;
+function getArray() {
+  callCount++;
+  return Array;
+}
+
+assert.deepEqual([1, 2, 3], new Array(...[1, 2, 3]));
+
+// Ensure the expression of the function being initialized is not copied.
+assert.deepEqual([1, 2, 3], new (getArray())(...[1, 2, 3]));
+assert.equal(callCount, 1);
diff --git a/test/fixtures/transformation/esnext-es6-spread/preserve-context.js b/test/fixtures/transformation/esnext-es6-spread/preserve-context.js
new file mode 100644
index 0000000000..e63f88e788
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/preserve-context.js
@@ -0,0 +1,35 @@
+var MATH = {
+  sum: function(...numbers) {
+    return numbers.reduce(this.add, 0);
+  },
+
+  add: function(a, b) {
+    return a + b;
+  }
+};
+
+assert.equal(MATH.sum(1, ...[2, 3]), 6);
+
+// Ensure that the below does not expand to this:
+//
+//   obj.getSelf().call.apply(obj.getSelf(), []);
+//
+
+var ops = [];
+var obj = {
+  getSelf: function() {
+    ops.push('getSelf');
+    return this;
+  },
+
+  doCall: function() {
+    ops.push('doCall', this);
+  }
+};
+
+obj.getSelf().doCall(...[]);
+assert.deepEqual(ops, ['getSelf', 'doCall', obj]);
+
+ops = [];
+obj['getSelf']().doCall(...[]);
+assert.deepEqual(ops, ['getSelf', 'doCall', obj]);
diff --git a/test/fixtures/transformation/esnext-es6-spread/simple-function-call.js b/test/fixtures/transformation/esnext-es6-spread/simple-function-call.js
new file mode 100644
index 0000000000..106bfa55be
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-spread/simple-function-call.js
@@ -0,0 +1,6 @@
+function sum(...numbers) {
+  return numbers.reduce(function(sum, n) { return n + sum; }, 0);
+}
+
+var numbers = [1, 2, 3];
+assert.equal(sum(...numbers), 6);
diff --git a/test/fixtures/transformation/esnext-es6-templates/multi-line.js b/test/fixtures/transformation/esnext-es6-templates/multi-line.js
new file mode 100644
index 0000000000..6d1be1c2bc
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-templates/multi-line.js
@@ -0,0 +1,4 @@
+var s = `a
+    b
+    c`;
+assert.equal(s, 'a\n    b\n    c');
diff --git a/test/fixtures/transformation/esnext-es6-templates/nested-interpolation.js b/test/fixtures/transformation/esnext-es6-templates/nested-interpolation.js
new file mode 100644
index 0000000000..83083e9fd0
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-templates/nested-interpolation.js
@@ -0,0 +1,4 @@
+assert.strictEqual(
+  `a${1}b${`${1+1}c`}3`,
+  'a1b2c3'
+);
diff --git a/test/fixtures/transformation/esnext-es6-templates/no-interpolation.js b/test/fixtures/transformation/esnext-es6-templates/no-interpolation.js
new file mode 100644
index 0000000000..1854b04ff5
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-templates/no-interpolation.js
@@ -0,0 +1,2 @@
+var s = `str`;
+assert.equal(s, 'str');
diff --git a/test/fixtures/transformation/esnext-es6-templates/raw-tagged-template-expression.js b/test/fixtures/transformation/esnext-es6-templates/raw-tagged-template-expression.js
new file mode 100644
index 0000000000..831ad050ab
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-templates/raw-tagged-template-expression.js
@@ -0,0 +1,6 @@
+function r(strings) {
+  assert.equal(strings.raw[0], '\\n');
+  return strings.raw.join('');
+}
+
+assert.equal(r `\n`, '\\n');
diff --git a/test/fixtures/transformation/esnext-es6-templates/simple-interpolation.js b/test/fixtures/transformation/esnext-es6-templates/simple-interpolation.js
new file mode 100644
index 0000000000..b96a02a543
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-templates/simple-interpolation.js
@@ -0,0 +1,2 @@
+var s = `1 + 1 = ${1 + 1}`;
+assert.equal(s, '1 + 1 = 2');
diff --git a/test/fixtures/transformation/esnext-es6-templates/tagged-template-expression.js b/test/fixtures/transformation/esnext-es6-templates/tagged-template-expression.js
new file mode 100644
index 0000000000..5b894c55ac
--- /dev/null
+++ b/test/fixtures/transformation/esnext-es6-templates/tagged-template-expression.js
@@ -0,0 +1,26 @@
+function tag(strings) {
+  var values = [].slice.call(arguments, 1);
+  assert.equal(strings[0], 'a');
+  assert.equal(strings[1], 'b');
+  assert.equal(values[0], 42);
+  return 'whatever';
+}
+assert.equal(tag `a${ 42 }b`, 'whatever');
+
+function tagInterpolateFirst(strings) {
+  var values = [].slice.call(arguments, 1);
+  assert.equal(strings[0], '');
+  assert.equal(strings[1], 'b');
+  assert.equal(values[0], 42);
+  return 'whatever';
+}
+assert.equal(tagInterpolateFirst `${ 42 }b`, 'whatever');
+
+function tagInterpolateLast(strings) {
+  var values = [].slice.call(arguments, 1);
+  assert.equal(strings[0], 'a');
+  assert.equal(strings[1], '');
+  assert.equal(values[0], 42);
+  return 'whatever';
+}
+assert.equal(tagInterpolateLast `a${ 42 }`, 'whatever');