Generator objects have [[Class]] === "Generator"

test/mjsunit/harmony/generators-objects.js

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-// Flags: --harmony-generators --harmony-scoping
+// Flags: --harmony-generators --harmony-scoping --allow-natives-syntax
 
 // Test instantations of generators.
 
 // Generators shouldn't allocate stack slots.  This test will abort in debug
 // mode if generators have stack slots.
 function TestContextAllocation() {
   function* g1(a, b, c) { yield 1; return [a, b, c]; }
   function* g2() { yield 1; return arguments; }
   function* g3() { yield 1; return this; }
   function* g4() { var x = 10; yield 1; return x; }
   // Temporary variable context allocation
   function* g5(l) { "use strict"; yield 1; for (let x in l) { yield x; } }
 
   g1();
   g2();
   g3();
   g4();
   g5(["foo"]);
 }
 TestContextAllocation();
 
 
 // Test the properties and prototype of a generator object.
 function TestGeneratorObject() {
   function* g() { yield 1; }
 
   var iter = g();
   assertSame(g.prototype, Object.getPrototypeOf(iter));
   assertTrue(iter instanceof g);
+  assertEquals("Generator", %ClassOf(iter));
+  assertEquals("[object Generator]", String(iter));
   assertEquals([], Object.getOwnPropertyNames(iter));
   assertTrue(iter !== g());
 
   // g() is the same as new g().
   iter = new g();
   assertSame(g.prototype, Object.getPrototypeOf(iter));
   assertTrue(iter instanceof g);
+  assertEquals("Generator", %ClassOf(iter));
+  assertEquals("[object Generator]", String(iter));
   assertEquals([], Object.getOwnPropertyNames(iter));
   assertTrue(iter !== new g());
 }
 TestGeneratorObject();
+
+
+// Test the methods of generator objects.
+function TestGeneratorObjectMethods() {
+  function* g() { yield 1; }
+  var iter = g();
+
+  function TestNonGenerator(non_generator) {
+    non_generator.next = iter.next;
+    non_generator.send = iter.send;
+    non_generator.throw = iter.throw;
+    non_generator.close = iter.close;

[Michael Starzinger, 2013/04/17 14:31:28]

I think the four assignments here are obsolete now.

+    assertThrows(function() { iter.next.call(non_generator); }, TypeError);
+    assertThrows(function() { iter.send.call(non_generator, 1); }, TypeError);
+    assertThrows(function() { iter.throw.call(non_generator, 1); }, TypeError);
+    assertThrows(function() { iter.close.call(non_generator); }, TypeError);
+  }
+
+  TestNonGenerator(1);
+  TestNonGenerator({});
+  TestNonGenerator(function(){});
+  TestNonGenerator(g);
+  TestNonGenerator(g.prototype);
+}
+TestGeneratorObjectMethods();