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/*
* Any copyright is dedicated to the Public Domain.
* http://creativecommons.org/licenses/publicdomain/
*/
function make_watcher(name) {
return function (id, oldv, newv) {
print("watched " + name + "[0]");
};
}
var o, p;
function f(flag) {
if (flag) {
o = arguments;
} else {
p = arguments;
o.watch(0, make_watcher('o'));
p.watch(0, make_watcher('p'));
/*
* Previously, the watchpoint implementation actually substituted its magic setter
* functions for the setters of shared shapes, and then 1) carefully ignored calls
* to its magic setter from unrelated objects, and 2) avoided restoring the
* original setter until all watchpoints on that shape had been removed.
*
* However, when the watchpoint code began using JSObject::changeProperty and
* js_ChangeNativePropertyAttrs to change shapes' setters, the shape tree code
* became conscious of the presence of watchpoints, and shared shapes between
* objects only when their watchpoint nature coincided. Clearing the magic setter
* from one object's shape would not affect other objects, because the
* watchpointed and non-watchpointed shapes were distinct if they were shared.
*
* Thus, the first unwatch call must go ahead and fix p's shape, even though a
* watchpoint exists on the same shape in o. o's watchpoint's presence shouldn't
* cause 'unwatch' to leave p's magic setter in place.
*/
/* DropWatchPointAndUnlock would see o's watchpoint, and not change p's property. */
p.unwatch(0);
/* DropWatchPointAndUnlock would fix o's property, but not p's; p's setter would be gone. */
o.unwatch(0);
/* This would fail to invoke the arguments object's setter. */
p[0] = 4;
/* And the formal parameter would not get updated. */
assertEq(flag, 4);
}
}
f(true);
f(false);
reportCompare(true, true);
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