js/src/tests/ecma_6/Generators/delegating-yield-3.js@6474c204b198 (annotated)
js/src/tests/ecma_6/Generators/delegating-yield-3.js
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | // Test yield* with iter.next and monkeypatching. |
| michael@0 | 2 | |
| michael@0 | 3 | function* g(n) { for (var i=0; i<n; i++) yield i; } |
| michael@0 | 4 | function* delegate(iter) { return yield* iter; } |
| michael@0 | 5 | var GeneratorObjectPrototype = Object.getPrototypeOf(g).prototype; |
| michael@0 | 6 | var GeneratorObjectPrototype_next = GeneratorObjectPrototype.next; |
| michael@0 | 7 | |
| michael@0 | 8 | // Monkeypatch next on an iterator. |
| michael@0 | 9 | var inner = g(20); |
| michael@0 | 10 | var outer = delegate(inner); |
| michael@0 | 11 | assertIteratorNext(outer, 0); |
| michael@0 | 12 | assertIteratorNext(outer, 1); |
| michael@0 | 13 | inner.next = function() { return 0; }; |
| michael@0 | 14 | // 42 yielded directly without re-boxing. |
| michael@0 | 15 | assertEq(0, outer.next()); |
| michael@0 | 16 | // Outer generator not terminated. |
| michael@0 | 17 | assertEq(0, outer.next()); |
| michael@0 | 18 | // Restore. |
| michael@0 | 19 | inner.next = GeneratorObjectPrototype_next; |
| michael@0 | 20 | assertIteratorNext(outer, 2); |
| michael@0 | 21 | // Repatch. |
| michael@0 | 22 | inner.next = function() { return { value: 42, done: true }; }; |
| michael@0 | 23 | assertIteratorDone(outer, 42); |
| michael@0 | 24 | |
| michael@0 | 25 | // Monkeypunch next on the prototype. |
| michael@0 | 26 | var inner = g(20); |
| michael@0 | 27 | var outer = delegate(inner); |
| michael@0 | 28 | assertIteratorNext(outer, 0); |
| michael@0 | 29 | assertIteratorNext(outer, 1); |
| michael@0 | 30 | GeneratorObjectPrototype.next = function() { return 0; }; |
| michael@0 | 31 | // 42 yielded directly without re-boxing. |
| michael@0 | 32 | assertEq(0, GeneratorObjectPrototype_next.call(outer)); |
| michael@0 | 33 | // Outer generator not terminated. |
| michael@0 | 34 | assertEq(0, GeneratorObjectPrototype_next.call(outer)); |
| michael@0 | 35 | // Restore. |
| michael@0 | 36 | GeneratorObjectPrototype.next = GeneratorObjectPrototype_next; |
| michael@0 | 37 | assertIteratorNext(outer, 2); |
| michael@0 | 38 | |
| michael@0 | 39 | if (typeof reportCompare == "function") |
| michael@0 | 40 | reportCompare(true, true); |
