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// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-function.prototype.bind
description: >
"length" value of a bound function defaults to 0.
Non-own and non-number "length" values of target function are ignored.
info: |
Function.prototype.bind ( thisArg, ...args )
[...]
5. Let targetHasLength be ? HasOwnProperty(Target, "length").
6. If targetHasLength is true, then
a. Let targetLen be ? Get(Target, "length").
b. If Type(targetLen) is not Number, let L be 0.
c. Else,
i. Set targetLen to ! ToInteger(targetLen).
ii. Let L be the larger of 0 and the result of targetLen minus the number of elements of args.
7. Else, let L be 0.
8. Perform ! SetFunctionLength(F, L).
[...]
features: [Symbol]
---*/
function foo() {}
Object.defineProperty(foo, "length", {value: undefined});
assert.sameValue(foo.bind(null, 1).length, 0, "undefined");
Object.defineProperty(foo, "length", {value: null});
assert.sameValue(foo.bind(null, 1).length, 0, "null");
Object.defineProperty(foo, "length", {value: true});
assert.sameValue(foo.bind(null, 1).length, 0, "boolean");
Object.defineProperty(foo, "length", {value: "1"});
assert.sameValue(foo.bind(null, 1).length, 0, "string");
Object.defineProperty(foo, "length", {value: Symbol("1")});
assert.sameValue(foo.bind(null, 1).length, 0, "symbol");
Object.defineProperty(foo, "length", {value: new Number(1)});
assert.sameValue(foo.bind(null, 1).length, 0, "Number object");
function bar() {}
Object.setPrototypeOf(bar, {length: 42});
assert(delete bar.length);
var bound = Function.prototype.bind.call(bar, null, 1);
assert.sameValue(bound.length, 0, "not own");
reportCompare(0, 0);
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