Fix bug where generators got closed prematurely.

test/mjsunit/es6/generators-states.js

Index: test/mjsunit/es6/generators-states.js
diff --git a/test/mjsunit/es6/generators-states.js b/test/mjsunit/es6/generators-states.js
index 0a2173a919fb9d24eadb1cc90dd6f29641d67822..d061dcda9fca45665ff948323f2849965a5d4bc6 100644
--- a/test/mjsunit/es6/generators-states.js
+++ b/test/mjsunit/es6/generators-states.js
@@ -25,6 +25,7 @@ function* throwGenerator() { yield iter.throw(new Bar); }
 // Throw on a suspendedStart iterator.
 iter = nextGenerator();
 assertThrows(function() { iter.throw(new Foo) }, Foo)
+assertIteratorIsClosed(iter);
 assertThrows(function() { iter.throw(new Foo) }, Foo)
 assertIteratorIsClosed(iter);
 
@@ -65,3 +66,20 @@ iter = (function* () {
 assertIteratorResult(3, false, iter.next());
 assertIteratorResult(4, false, iter.next());
 assertIteratorIsClosed(iter);
+
+
+// return that doesn't close

[Michael Starzinger, 2016/01/25 12:56:05]

nit: Please capitalize and punctuate comment.

+{
+  let g = function*() { try {return 42} finally {yield 43} };
+
+  let x = g();
+  assertEquals({value: 43, done: false}, x.next());
+  assertEquals({value: 42, done: true}, x.next());
+}
+{
+  let x;
+  let g = function*() { try {return 42} finally {x.throw(666)} };

[Michael Starzinger, 2016/01/25 12:56:05]

As discussed offline, can we add another test case of the following structure on
top of the existings ones here, just to make this clearer:

let x;
let g = function*() {
  try { return 42 } finally {
    try { x.throw(666) } catch(e) {}
  }
}

x = g();
assertEquals({value: 42, done: true}, x.next());

+
+  x = g();
+  assertThrows(() => x.next(), TypeError);  // still executing
+}