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// Test that Array.prototype.shift doesn't call the [[HasProperty]] internal
// method of objects when retrieving the element at index 0.
var log = [];
var array = [];
var proxy = new Proxy(array, new Proxy({}, {
get(t, trap, r) {
return (t, pk, ...more) => {
log.push(`${trap}:${String(pk)}`);
return Reflect[trap](t, pk, ...more);
};
}
}));
var result;
result = Array.prototype.shift.call(proxy);
assertEqArray(log, [
"get:length",
"set:length", "getOwnPropertyDescriptor:length", "defineProperty:length"
]);
assertEq(result, undefined);
log.length = 0;
array.push(1);
result = Array.prototype.shift.call(proxy);
assertEqArray(log, [
"get:length",
"get:0",
"deleteProperty:0",
"set:length", "getOwnPropertyDescriptor:length", "defineProperty:length"
]);
assertEq(result, 1);
log.length = 0;
array.push(2, 3);
result = Array.prototype.shift.call(proxy);
assertEqArray(log, [
"get:length",
"get:0",
"has:1", "get:1", "set:0", "getOwnPropertyDescriptor:0", "defineProperty:0",
"deleteProperty:1",
"set:length", "getOwnPropertyDescriptor:length", "defineProperty:length"
]);
assertEq(result, 2);
log.length = 0;
array.push(4, 5);
result = Array.prototype.shift.call(proxy);
assertEqArray(log, [
"get:length",
"get:0",
"has:1", "get:1", "set:0", "getOwnPropertyDescriptor:0", "defineProperty:0",
"has:2", "get:2", "set:1", "getOwnPropertyDescriptor:1", "defineProperty:1",
"deleteProperty:2",
"set:length", "getOwnPropertyDescriptor:length", "defineProperty:length"
]);
assertEq(result, 3);
if (typeof reportCompare === "function")
reportCompare(true, true);