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var toString = Object.prototype.toString;
var iter = 500;
function testConstant() {
for (var i = 0; i < iter; i++) {
assertEq(({}).toString(), "[object Object]");
assertEq(toString.call([]), "[object Array]");
assertEq(toString.call(Math.abs), "[object Function]");
}
}
testConstant();
function testOwnToStringTag() {
var stringify = o => toString.call(o);
var o = {};
for (var i = 0; i < iter; i++)
assertEq(stringify(o), "[object Object]");
o[Symbol.toStringTag] = "foo";
for (var i = 0; i < iter; i++)
assertEq(stringify(o), "[object foo]");
}
testOwnToStringTag();
function testDynamic() {
var arr = [{}, [], new Date, /a/];
var expected = ["[object Object]", "[object Array]", "[object Date]", "[object RegExp]"];
for (var i = 0; i < iter; i++) {
for (var j = 0; j < arr.length; j++)
assertEq(toString.call(arr[j]), expected[j]);
}
}
testDynamic();
function testToStringTagProto() {
var c = 0;
Object.defineProperty(Date.prototype, Symbol.toStringTag, {get() { c++; return "evil"; }});
var arr = [{}, [], new Date, /a/];
var expected = ["[object Object]", "[object Array]", "[object evil]", "[object RegExp]"];
for (var i = 0; i < iter; i++) {
for (var j = 0; j < arr.length; j++)
assertEq(toString.call(arr[j]), expected[j]);
}
assertEq(c, iter);
}
testToStringTagProto();
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