yield* calls @@iterator on iterable

test/mjsunit/harmony/generators-iteration.js

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 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --harmony-generators --expose-gc
+// Flags: --harmony-generators --expose-gc --harmony-symbols

[rossberg, 2014/08/05 11:58:02]

Note: --harmony-symbols should be unnecessary now.

+// Flags: --harmony-iteration
 
 // Test generator iteration.
 
 var GeneratorFunction = (function*(){yield 1;}).__proto__.constructor;
 
 function assertIteratorResult(value, done, result) {
   assertEquals({ value: value, done: done}, result);
 }
 
 function assertIteratorIsClosed(iter) {
@@ skipping 309 matching lines @@
 TestGenerator(
     function* g27() {
       yield
       3
       return
     },
     [undefined, undefined],
     "foo",
     [undefined, undefined]);
 
+// TODO(wingo): We should use TestGenerator for these, except that
+// currently yield* will unconditionally propagate a throw() to the
+// delegate iterator, which fails for these iterators that don't have
+// throw().  See http://code.google.com/p/v8/issues/detail?id=3484.
+(function() {
+    function* g28() {
+      yield* [1, 2, 3];
+    }
+    var iter = g28();
+    assertIteratorResult(1, false, iter.next());
+    assertIteratorResult(2, false, iter.next());
+    assertIteratorResult(3, false, iter.next());
+    assertIteratorResult(undefined, true, iter.next());
+})();
+
+(function() {
+    function* g29() {
+      yield* "abc";
+    }
+    var iter = g29();
+    assertIteratorResult("a", false, iter.next());
+    assertIteratorResult("b", false, iter.next());
+    assertIteratorResult("c", false, iter.next());
+    assertIteratorResult(undefined, true, iter.next());
+})();
+
 // Generator function instances.
 TestGenerator(GeneratorFunction(),
               [undefined],
               "foo",
               [undefined]);
 
 TestGenerator(new GeneratorFunction(),
               [undefined],
               "foo",
               [undefined]);
@@ skipping 18 matching lines @@
     "foo",
     [42, undefined]);
 
 // Test that yield* re-yields received results without re-boxing.
 function TestDelegatingYield() {
   function results(results) {
     var i = 0;
     function next() {
       return results[i++];
     }
-    return { next: next }
+    var iter = { next: next };
+    var ret = {};
+    ret[Symbol.iterator] = function() { return iter; };
+    return ret;
   }
   function* yield_results(expected) {
     return yield* results(expected);
   }
-  function collect_results(iter) {
+  function collect_results(iterable) {
+    var iter = iterable[Symbol.iterator]();
     var ret = [];
     var result;
     do {
       result = iter.next();
       ret.push(result);
     } while (!result.done);
     return ret;
   }
   // We have to put a full result for the end, because the return will re-box.
   var expected = [{value: 1}, 13, "foo", {value: 34, done: true}];
@@ skipping 247 matching lines @@
   function TestThrowRecursion() {
     function* g() { yield iter.throw(1); }
     var iter = g();
     return iter.next();
   }
   assertThrows(TestNextRecursion, Error);
   assertThrows(TestSendRecursion, Error);
   assertThrows(TestThrowRecursion, Error);
 }
 TestRecursion();