43 lines
1.3 KiB
JavaScript
43 lines
1.3 KiB
JavaScript
'use strict';
|
|
|
|
var $TypeError = require('es-errors/type');
|
|
|
|
var Call = require('./Call');
|
|
var Get = require('./Get');
|
|
var ToBoolean = require('./ToBoolean');
|
|
var IsCallable = require('./IsCallable');
|
|
var ToString = require('./ToString');
|
|
var Type = require('./Type');
|
|
|
|
var isInteger = require('../helpers/isInteger');
|
|
|
|
module.exports = function FindViaPredicate(O, len, direction, predicate, thisArg) {
|
|
if (Type(O) !== 'Object') {
|
|
throw new $TypeError('Assertion failed: Type(O) is not Object');
|
|
}
|
|
if (!isInteger(len) || len < 0) {
|
|
throw new $TypeError('Assertion failed: len must be a non-negative integer');
|
|
}
|
|
if (direction !== 'ascending' && direction !== 'descending') {
|
|
throw new $TypeError('Assertion failed: direction must be "ascending" or "descending"');
|
|
}
|
|
|
|
if (!IsCallable(predicate)) {
|
|
throw new $TypeError('predicate must be callable'); // step 1
|
|
}
|
|
|
|
for ( // steps 2-4
|
|
var k = direction === 'ascending' ? 0 : len - 1;
|
|
direction === 'ascending' ? k < len : k >= 0;
|
|
k += 1
|
|
) {
|
|
var Pk = ToString(k); // step 4.a
|
|
var kValue = Get(O, Pk); // step 4.c
|
|
var testResult = Call(predicate, thisArg, [kValue, k, O]); // step 4.d
|
|
if (ToBoolean(testResult)) {
|
|
return { '[[Index]]': k, '[[Value]]': kValue }; // step 4.e
|
|
}
|
|
}
|
|
return { '[[Index]]': -1, '[[Value]]': void undefined }; // step 5
|
|
};
|