Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 | 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 91x 91x 91x 91x 1x 1x 1x 1x 1x 1x 1x 1x 1x 35x 35x 35x 49x 11x 11x 49x 24x 35x 1x 1x 1x 1x 1x 1x 1x 1x 1x 48x 48x 48x 48x 48x 48x 48x 48x 8x 8x 48x 61x 61x 20x 20x 61x 20x 20x 48x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 30x 30x 6x 6x 24x 30x 1x 1x 1x 1x 1x | /**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// MODULES //
var objectKeys = require( '@stdlib/utils/keys' );
// FUNCTIONS //
/**
* Tests if a value is an object.
*
* ## Notes
*
* - The function excludes `null`.
*
* @private
* @param {*} value - value to test
* @returns {boolean} boolean indicating if a value is an object
*/
function isObject( value ) {
var type = typeof value;
return ( value !== null && ( type === 'object' || type === 'function' ) );
}
/**
* Tests if the seen array contains a search value.
*
* @private
* @param {Array} seen - array of seen objects
* @param {*} searchValue - search value
* @returns {boolean} boolean indicating whether array contains search value
*/
function contains( seen, searchValue ) {
var i;
for ( i = 0; i < seen.length; i++ ) {
if ( seen[ i ] === searchValue ) {
return true;
}
}
return false;
}
/**
* Tests if an object contains a circular reference by recursively traversing object keys.
*
* @private
* @param {Object} obj - object to test
* @param {Array} seen - array of seen objects
* @returns {boolean} boolean indicating whether object contains a circular reference
*/
function isCircObj( obj, seen ) {
var keys;
var val;
var i;
seen.push( obj );
keys = objectKeys( obj );
if ( keys.length === 0 ) {
return false;
}
for ( i = 0; i < keys.length; i++ ) {
val = obj[ keys[ i ] ];
if ( isObject( val ) && ( contains( seen, val ) || isCircObj( val, seen ) ) ) { // eslint-disable-line max-len
return true;
}
}
seen.pop( obj );
return false;
}
// MAIN //
/**
* Tests if an object-like value contains a circular reference.
*
* @param {*} value - value to test
* @returns {boolean} boolean indicating whether value is object-like and contains a circular reference
*
* @example
* var obj = {
* 'a': 'beep',
* 'b': {
* 'c': 'boop'
* }
* };
* obj.b.self = obj;
* var bool = isCircular( obj );
* // returns true
*
* @example
* var arr = [ 1, 2, 3 ];
* arr.push( arr );
* var bool = isCircular( arr );
* // returns true
*
* @example
* var bool = isCircular( {} );
* // returns false
*
* @example
* var bool = isCircular( null );
* // returns false
*/
function isCircular( value ) {
if ( !isObject( value ) ) {
return false;
}
return isCircObj( value, [] );
}
// EXPORTS //
module.exports = isCircular;
|