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// Assigning to a proxy with no set handler causes the proxy's
// getOwnPropertyDescriptor handler to be called just before defineProperty
// in some cases. (ES6 draft rev 28, 2014 Oct 14, 9.1.9 step 5.c.)
var attrs = ["configurable", "enumerable", "writable", "value", "get", "set"];
function test(target, id, existingDesc, expectedDesc) {
var log = "";
var p = new Proxy(target, {
getOwnPropertyDescriptor(t, idarg) {
assertEq(idarg, id);
log += "g";
return existingDesc;
},
defineProperty(t, idarg, desc) {
assertEq(idarg, id);
for (var attr of attrs) {
var args = JSON.stringify([target, id, existingDesc]).slice(1, -1);
assertEq(attr in desc, attr in expectedDesc,
`test(${args}), checking existence of desc.${attr}`);
assertEq(desc[attr], expectedDesc[attr],
`test(${args}), checking value of desc.${attr}`);
}
log += "d";
return true;
}
});
p[id] = "pizza";
assertEq(log, "gd");
}
var fullDesc = {
configurable: true,
enumerable: true,
writable: true,
value: "pizza"
};
var valueOnlyDesc = {
value: "pizza"
};
var sealedDesc = {
configurable: false,
enumerable: true,
writable: true,
value: "pizza"
};
test({}, "x", undefined, fullDesc);
test({}, "x", fullDesc, valueOnlyDesc);
test({x: 1}, "x", undefined, fullDesc);
test({x: 1}, "x", fullDesc, valueOnlyDesc);
test(Object.seal({x: 1}), "x", sealedDesc, valueOnlyDesc);
test(Object.create({x: 1}), "x", undefined, fullDesc);
test([0, 1, 2], "2", undefined, fullDesc);
test([0, 1, 2], "2", fullDesc, valueOnlyDesc);
test([0, 1, 2], "3", undefined, fullDesc);
test([0, 1, 2], "3", fullDesc, valueOnlyDesc);
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