locutus
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Locutus other languages' standard libraries to JavaScript for fun and educational purposes
93 lines (92 loc) • 4.45 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.is_array = is_array;
const _phpRuntimeState_ts_1 = require("../_helpers/_phpRuntimeState.js");
const ini_get_ts_1 = require("../info/ini_get.js");
const hasNumericLength = (value) => value !== null && typeof value === 'object' && typeof (0, _phpRuntimeState_ts_1.getPhpObjectEntry)(value, 'length') === 'number';
function is_array(mixedVar) {
// discuss at: https://locutus.io/php/is_array/
// original by: Kevin van Zonneveld (https://kvz.io)
// improved by: Legaev Andrey
// improved by: Onno Marsman (https://twitter.com/onnomarsman)
// improved by: Brett Zamir (https://brett-zamir.me)
// improved by: Nathan Sepulveda
// improved by: Brett Zamir (https://brett-zamir.me)
// bugfixed by: Cord
// bugfixed by: Manish
// bugfixed by: Brett Zamir (https://brett-zamir.me)
// note 1: In Locutus, javascript objects are like php associative arrays,
// note 1: thus JavaScript objects will also
// note 1: return true in this function (except for objects which inherit properties,
// note 1: being thus used as objects),
// note 1: unless you do ini_set('locutus.objectsAsArrays', 0),
// note 1: in which case only genuine JavaScript arrays
// note 1: will return true
// example 1: is_array(['Kevin', 'van', 'Zonneveld'])
// returns 1: true
// example 2: is_array('Kevin van Zonneveld')
// returns 2: false
// example 3: is_array({0: 'Kevin', 1: 'van', 2: 'Zonneveld'})
// returns 3: true
// example 4: ini_set('locutus.objectsAsArrays', 0)
// example 4: is_array({0: 'Kevin', 1: 'van', 2: 'Zonneveld'})
// returns 4: false
// example 5: is_array(function tmp_a (){ this.name = 'Kevin' })
// returns 5: false
const _getFuncName = function (fn) {
const name = /\W*function\s+([\w$]+)\s*\(/.exec(String(fn));
if (!name) {
return '(Anonymous)';
}
return name[1] ?? '(Anonymous)';
};
const _isArray = function (mixedVar) {
// return Array.isArray(mixedVar);
// The above works, but let's do the even more stringent approach:
// (since Object.prototype.toString could be overridden)
// Null, Not an object, no length property so couldn't be an Array (or String)
if (!hasNumericLength(mixedVar)) {
return false;
}
const candidate = mixedVar;
const len = candidate.length;
candidate[candidate.length] = 'bogus';
// The only way I can think of to get around this (or where there would be trouble)
// would be to have an object defined
// with a custom "length" getter which changed behavior on each call
// (or a setter to mess up the following below) or a custom
// setter for numeric properties, but even that would need to listen for
// specific indexes; but there should be no false negatives
// and such a false positive would need to rely on later JavaScript
// innovations like __defineSetter__
if (len !== candidate.length) {
// We know it's an array since length auto-changed with the addition of a
// numeric property at its length end, so safely get rid of our bogus element
candidate.length -= 1;
return true;
}
// Get rid of the property we added onto a non-array object; only possible
// side-effect is if the user adds back the property later, it will iterate
// this property in the older order placement in IE (an order which should not
// be depended on anyways)
delete candidate[candidate.length];
return false;
};
if (!mixedVar || typeof mixedVar !== 'object') {
return false;
}
const isArray = _isArray(mixedVar);
if (isArray) {
return true;
}
const iniVal = (0, ini_get_ts_1.ini_get)('locutus.objectsAsArrays') || 'on';
if (iniVal === 'on') {
const asString = Object.prototype.toString.call(mixedVar);
const asFunc = _getFuncName((0, _phpRuntimeState_ts_1.getPhpObjectEntry)(mixedVar, 'constructor'));
if (asString === '[object Object]' && asFunc === 'Object') {
// Most likely a literal and intended as assoc. array
return true;
}
}
return false;
}