Implement yield* (delegating yield)

test/mjsunit/harmony/generators-iteration.js

Index: test/mjsunit/harmony/generators-iteration.js
diff --git a/test/mjsunit/harmony/generators-iteration.js b/test/mjsunit/harmony/generators-iteration.js
index 17a6e804f5c144b0891a73ecafe4c15035cfa4c5..3bfcf0f567436e9e54014c0ef22e9b4631f42295 100644
--- a/test/mjsunit/harmony/generators-iteration.js
+++ b/test/mjsunit/harmony/generators-iteration.js
@@ -307,6 +307,16 @@ TestGenerator(
     "foo",
     [2, "1foo3", 5, "4foo6", "foofoo"]);
 
+// Delegating yield
+TestGenerator(
+    function* g26() {
+      function* g() { var x = yield 1; yield 2; yield x; return 3; }
+      yield* g();
+    },
+    [1, 2, undefined, undefined],
+    "foo",
+    [1, 2, "foo", undefined]);
+
 function TestTryCatch() {
   function* g() { yield 1; try { yield 2; } catch (e) { yield e; } yield 3; }
   function Sentinel() {}
@@ -346,6 +356,7 @@ function TestTryCatch() {
   assertThrows(function() { iter.throw(new Sentinel); }, Sentinel);
   assertThrows(function() { iter.next(); }, Error);
 
+  // ***
   iter = g();
   assertIteratorResult(1, false, iter.next());
   assertIteratorResult(2, false, iter.next());
@@ -360,6 +371,15 @@ function TestTryCatch() {
   assertIteratorResult(3, false, iter.next());
   assertIteratorResult(undefined, true, iter.next());
   assertThrows(function() { iter.next(); }, Error);
+
+  // same as *** above with delegate

[rossberg, 2013/05/13 11:14:56]

Would be cool if all these Test functions were factored such that they take a
generator as argument and then run all tests with that. Then you could simply
invoke it twice with both the flat and the delegating generator (and potentially
other variations) and avoid code duplication.

+  iter = (function* () { yield* g(); })();
+  assertIteratorResult(1, false, iter.next());
+  assertIteratorResult(2, false, iter.next());
+  var exn = new Sentinel;
+  assertIteratorResult(exn, false, iter.throw(exn));
+  assertThrows(function() { iter.throw(new Sentinel); }, Sentinel);
+  assertThrows(function() { iter.next(); }, Error);
 }
 TestTryCatch();
 
@@ -393,6 +413,7 @@ function TestTryFinally() {
   assertThrows(function() { iter.next(); }, Sentinel);
   assertThrows(function() { iter.next(); }, Error);
 
+  // ***
   iter = g();
   assertIteratorResult(1, false, iter.next());
   assertIteratorResult(2, false, iter.next());
@@ -422,6 +443,14 @@ function TestTryFinally() {
   assertIteratorResult(4, false, iter.next());
   assertIteratorResult(undefined, true, iter.next());
   assertThrows(function() { iter.next(); }, Error);
+
+  // same as *** above with delegate
+  iter = (function* () { yield* g(); })();
+  assertIteratorResult(1, false, iter.next());
+  assertIteratorResult(2, false, iter.next());
+  assertIteratorResult(3, false, iter.throw(new Sentinel));
+  assertThrows(function() { iter.throw(new Sentinel2); }, Sentinel2);
+  assertThrows(function() { iter.next(); }, Error);
 }
 TestTryFinally();
 
@@ -476,6 +505,7 @@ function TestNestedTry() {
   assertIteratorResult(undefined, true, iter.next());
   assertThrows(function() { iter.next(); }, Error);
 
+  // ***
   iter = g();
   assertIteratorResult(1, false, iter.next());
   assertIteratorResult(2, false, iter.next());
@@ -495,6 +525,16 @@ function TestNestedTry() {
   assertThrows(function() { iter.next(); }, Sentinel2);
   assertThrows(function() { iter.next(); }, Error);
 
+  // same as *** above with delegate
+  iter = (function* () { yield* g(); })();
+  assertIteratorResult(1, false, iter.next());
+  assertIteratorResult(2, false, iter.next());
+  var exn = new Sentinel;
+  assertIteratorResult(exn, false, iter.throw(exn));
+  assertIteratorResult(4, false, iter.throw(new Sentinel2));
+  assertThrows(function() { iter.next(); }, Sentinel2);
+  assertThrows(function() { iter.next(); }, Error);
+
   // That's probably enough.
 }
 TestNestedTry();