You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
75 lines
2.1 KiB
75 lines
2.1 KiB
'use strict'; |
|
|
|
var hasSymbols = typeof Symbol === 'function' && typeof Symbol.iterator === 'symbol'; |
|
|
|
var isPrimitive = require('./helpers/isPrimitive'); |
|
var isCallable = require('is-callable'); |
|
var isDate = require('is-date-object'); |
|
var isSymbol = require('is-symbol'); |
|
|
|
var ordinaryToPrimitive = function OrdinaryToPrimitive(O, hint) { |
|
if (typeof O === 'undefined' || O === null) { |
|
throw new TypeError('Cannot call method on ' + O); |
|
} |
|
if (typeof hint !== 'string' || (hint !== 'number' && hint !== 'string')) { |
|
throw new TypeError('hint must be "string" or "number"'); |
|
} |
|
var methodNames = hint === 'string' ? ['toString', 'valueOf'] : ['valueOf', 'toString']; |
|
var method, result, i; |
|
for (i = 0; i < methodNames.length; ++i) { |
|
method = O[methodNames[i]]; |
|
if (isCallable(method)) { |
|
result = method.call(O); |
|
if (isPrimitive(result)) { |
|
return result; |
|
} |
|
} |
|
} |
|
throw new TypeError('No default value'); |
|
}; |
|
|
|
var GetMethod = function GetMethod(O, P) { |
|
var func = O[P]; |
|
if (func !== null && typeof func !== 'undefined') { |
|
if (!isCallable(func)) { |
|
throw new TypeError(func + ' returned for property ' + P + ' of object ' + O + ' is not a function'); |
|
} |
|
return func; |
|
} |
|
return void 0; |
|
}; |
|
|
|
// http://www.ecma-international.org/ecma-262/6.0/#sec-toprimitive |
|
module.exports = function ToPrimitive(input) { |
|
if (isPrimitive(input)) { |
|
return input; |
|
} |
|
var hint = 'default'; |
|
if (arguments.length > 1) { |
|
if (arguments[1] === String) { |
|
hint = 'string'; |
|
} else if (arguments[1] === Number) { |
|
hint = 'number'; |
|
} |
|
} |
|
|
|
var exoticToPrim; |
|
if (hasSymbols) { |
|
if (Symbol.toPrimitive) { |
|
exoticToPrim = GetMethod(input, Symbol.toPrimitive); |
|
} else if (isSymbol(input)) { |
|
exoticToPrim = Symbol.prototype.valueOf; |
|
} |
|
} |
|
if (typeof exoticToPrim !== 'undefined') { |
|
var result = exoticToPrim.call(input, hint); |
|
if (isPrimitive(result)) { |
|
return result; |
|
} |
|
throw new TypeError('unable to convert exotic object to primitive'); |
|
} |
|
if (hint === 'default' && (isDate(input) || isSymbol(input))) { |
|
hint = 'string'; |
|
} |
|
return ordinaryToPrimitive(input, hint === 'default' ? 'number' : hint); |
|
};
|
|
|