michael@0: /*
michael@0:  * Any copyright is dedicated to the Public Domain.
michael@0:  * http://creativecommons.org/licenses/publicdomain/
michael@0:  */
michael@0: 
michael@0: /* Create an object with a JavaScript setter. */
michael@0: var firstSetterCount;
michael@0: var o = { w:2, set x(v) { firstSetterCount++; } };
michael@0: 
michael@0: /*
michael@0:  * Put the object in dictionary mode, so that JSObject::putProperty will 
michael@0:  * mutate its shapes instead of creating new ones.
michael@0:  */
michael@0: delete o.w;
michael@0: 
michael@0: /* A stock watcher function. */
michael@0: var watcherCount;
michael@0: function watcher(id, oldval, newval) { watcherCount++; return newval; }
michael@0: 
michael@0: /*
michael@0:  * Place a watchpoint on the property. The property's shape now has the
michael@0:  * watchpoint setter, with the original setter saved in the watchpoint
michael@0:  * structure.
michael@0:  */
michael@0: o.watch('x', watcher);
michael@0: 
michael@0: /*
michael@0:  * Replace the setter with a new setter. The shape should get updated to
michael@0:  * refer to the new setter, and then the watchpoint setter should be
michael@0:  * re-established.
michael@0:  */
michael@0: var secondSetterCount;
michael@0: Object.defineProperty(o, 'x', { set: function () { secondSetterCount++ } });
michael@0: 
michael@0: /*
michael@0:  * Assign to the property. This should trigger the watchpoint and the new setter.
michael@0:  */
michael@0: watcherCount = firstSetterCount = secondSetterCount = 0;
michael@0: o.x = 3;
michael@0: assertEq(watcherCount, 1);
michael@0: assertEq(firstSetterCount, 0);
michael@0: assertEq(secondSetterCount, 1);
michael@0: 
michael@0: reportCompare(true, true);