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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 14.1.6
description: >
Default parameters' effect on function length
info: |
Function length is counted by the non initialized parameters in the left.
9.2.4 FunctionInitialize (F, kind, ParameterList, Body, Scope)
[...]
2. Let len be the ExpectedArgumentCount of ParameterList.
3. Perform ! DefinePropertyOrThrow(F, "length", PropertyDescriptor{[[Value]]:
len, [[Writable]]: false, [[Enumerable]]: false, [[Configurable]]: true}).
[...]
FormalsList : FormalParameter
1. If HasInitializer of FormalParameter is true return 0
2. Return 1.
FormalsList : FormalsList , FormalParameter
1. Let count be the ExpectedArgumentCount of FormalsList.
2. If HasInitializer of FormalsList is true or HasInitializer of
FormalParameter is true, return count.
3. Return count+1.
features: [default-parameters]
includes: [propertyHelper.js]
---*/
var f1 = function (x = 42) {};
verifyProperty(f1, "length", {
value: 0,
writable: false,
enumerable: false,
configurable: true,
});
var f2 = function (x = 42, y) {};
verifyProperty(f2, "length", {
value: 0,
writable: false,
enumerable: false,
configurable: true,
});
var f3 = function (x, y = 42) {};
verifyProperty(f3, "length", {
value: 1,
writable: false,
enumerable: false,
configurable: true,
});
var f4 = function (x, y = 42, z) {};
verifyProperty(f4, "length", {
value: 1,
writable: false,
enumerable: false,
configurable: true,
});
reportCompare(0, 0);