57 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			57 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| var baseIteratee = require('./_baseIteratee'),
 | |
|     createInverter = require('./_createInverter');
 | |
| 
 | |
| /** Used for built-in method references. */
 | |
| var objectProto = Object.prototype;
 | |
| 
 | |
| /** Used to check objects for own properties. */
 | |
| var hasOwnProperty = objectProto.hasOwnProperty;
 | |
| 
 | |
| /**
 | |
|  * Used to resolve the
 | |
|  * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
 | |
|  * of values.
 | |
|  */
 | |
| var nativeObjectToString = objectProto.toString;
 | |
| 
 | |
| /**
 | |
|  * This method is like `_.invert` except that the inverted object is generated
 | |
|  * from the results of running each element of `object` thru `iteratee`. The
 | |
|  * corresponding inverted value of each inverted key is an array of keys
 | |
|  * responsible for generating the inverted value. The iteratee is invoked
 | |
|  * with one argument: (value).
 | |
|  *
 | |
|  * @static
 | |
|  * @memberOf _
 | |
|  * @since 4.1.0
 | |
|  * @category Object
 | |
|  * @param {Object} object The object to invert.
 | |
|  * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
 | |
|  * @returns {Object} Returns the new inverted object.
 | |
|  * @example
 | |
|  *
 | |
|  * var object = { 'a': 1, 'b': 2, 'c': 1 };
 | |
|  *
 | |
|  * _.invertBy(object);
 | |
|  * // => { '1': ['a', 'c'], '2': ['b'] }
 | |
|  *
 | |
|  * _.invertBy(object, function(value) {
 | |
|  *   return 'group' + value;
 | |
|  * });
 | |
|  * // => { 'group1': ['a', 'c'], 'group2': ['b'] }
 | |
|  */
 | |
| var invertBy = createInverter(function(result, value, key) {
 | |
|   if (value != null &&
 | |
|       typeof value.toString != 'function') {
 | |
|     value = nativeObjectToString.call(value);
 | |
|   }
 | |
| 
 | |
|   if (hasOwnProperty.call(result, value)) {
 | |
|     result[value].push(key);
 | |
|   } else {
 | |
|     result[value] = [key];
 | |
|   }
 | |
| }, baseIteratee);
 | |
| 
 | |
| module.exports = invertBy;
 |