37 lines
1.1 KiB
JavaScript
37 lines
1.1 KiB
JavaScript
|
'use strict';
|
||
|
|
|
||
|
|
var GetIntrinsic = require('get-intrinsic');
|
||
|
|
var $concat = GetIntrinsic('%Array.prototype.concat%');
|
||
|
|
|
||
|
|
var callBind = require('call-bind');
|
||
|
|
|
||
|
|
var callBound = require('call-bind/callBound');
|
||
|
|
var $slice = callBound('Array.prototype.slice');
|
||
|
|
|
||
|
|
var hasSymbols = require('has-symbols/shams')();
|
||
|
|
var isConcatSpreadable = hasSymbols && Symbol.isConcatSpreadable;
|
||
|
|
|
||
|
|
var empty = [];
|
||
|
|
if (isConcatSpreadable) {
|
||
|
|
empty[isConcatSpreadable] = true;
|
||
|
|
}
|
||
|
|
var $concatApply = isConcatSpreadable ? callBind.apply($concat, empty) : null;
|
||
|
|
var $concatCall = isConcatSpreadable ? null : callBind($concat, empty);
|
||
|
|
|
||
|
|
var isArray = isConcatSpreadable ? require('isarray') : null;
|
||
|
|
|
||
|
|
module.exports = isConcatSpreadable
|
||
|
|
// eslint-disable-next-line no-unused-vars
|
||
|
|
? function safeArrayConcat(item) {
|
||
|
|
for (var i = 0; i < arguments.length; i += 1) {
|
||
|
|
var arg = arguments[i];
|
||
|
|
if (arg && typeof arg === 'object' && typeof arg[isConcatSpreadable] === 'boolean') {
|
||
|
|
var arr = isArray(arg) ? $slice(arg) : [arg];
|
||
|
|
arr[isConcatSpreadable] = true; // shadow the property. TODO: use [[Define]]
|
||
|
|
arguments[i] = arr;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return $concatApply(arguments);
|
||
|
|
}
|
||
|
|
: $concatCall;
|