The Tor Browser / file comparison
comparison: js/src/tests/ecma_5/extensions/watchpoint-deletes-JSPropertyOp-setter.js
js/src/tests/ecma_5/extensions/watchpoint-deletes-JSPropertyOp-setter.js
- branch
- TOR_BUG_9701
- changeset 9
- a63d609f5ebe
equal
deleted
inserted
replaced
| -1:000000000000 | 0:ace441990c81 |
|---|---|
| 1 /* | |
| 2 * Any copyright is dedicated to the Public Domain. | |
| 3 * http://creativecommons.org/licenses/publicdomain/ | |
| 4 */ | |
| 5 | |
| 6 function make_watcher(name) { | |
| 7 return function (id, oldv, newv) { | |
| 8 print("watched " + name + "[0]"); | |
| 9 }; | |
| 10 } | |
| 11 | |
| 12 var o, p; | |
| 13 function f(flag) { | |
| 14 if (flag) { | |
| 15 o = arguments; | |
| 16 } else { | |
| 17 p = arguments; | |
| 18 o.watch(0, make_watcher('o')); | |
| 19 p.watch(0, make_watcher('p')); | |
| 20 | |
| 21 /* | |
| 22 * Previously, the watchpoint implementation actually substituted its magic setter | |
| 23 * functions for the setters of shared shapes, and then 1) carefully ignored calls | |
| 24 * to its magic setter from unrelated objects, and 2) avoided restoring the | |
| 25 * original setter until all watchpoints on that shape had been removed. | |
| 26 * | |
| 27 * However, when the watchpoint code began using JSObject::changeProperty and | |
| 28 * js_ChangeNativePropertyAttrs to change shapes' setters, the shape tree code | |
| 29 * became conscious of the presence of watchpoints, and shared shapes between | |
| 30 * objects only when their watchpoint nature coincided. Clearing the magic setter | |
| 31 * from one object's shape would not affect other objects, because the | |
| 32 * watchpointed and non-watchpointed shapes were distinct if they were shared. | |
| 33 * | |
| 34 * Thus, the first unwatch call must go ahead and fix p's shape, even though a | |
| 35 * watchpoint exists on the same shape in o. o's watchpoint's presence shouldn't | |
| 36 * cause 'unwatch' to leave p's magic setter in place. | |
| 37 */ | |
| 38 | |
| 39 /* DropWatchPointAndUnlock would see o's watchpoint, and not change p's property. */ | |
| 40 p.unwatch(0); | |
| 41 | |
| 42 /* DropWatchPointAndUnlock would fix o's property, but not p's; p's setter would be gone. */ | |
| 43 o.unwatch(0); | |
| 44 | |
| 45 /* This would fail to invoke the arguments object's setter. */ | |
| 46 p[0] = 4; | |
| 47 | |
| 48 /* And the formal parameter would not get updated. */ | |
| 49 assertEq(flag, 4); | |
| 50 } | |
| 51 } | |
| 52 | |
| 53 f(true); | |
| 54 f(false); | |
| 55 | |
| 56 reportCompare(true, true); |
