angularjs-filters.js

/*
 * Exemplo:
 * var users = [
 *   {name: 'Victor Queiroz'},
 *   {name: 'João Bosco'},
 *   {nickname: {myNickname: 'Ruan Jordão'}}
 * ];
 *
 * Aplicando o filtro:
 * {{ users | pluck:'name | nickname.myNickname' | join:', ' }}
 *
 * Retorno:
 * Victor Queiroz, João Bosco, Ruan Jordão
 *
 * Dependências:
 * - VanillaJS
 */
angular.module('filters', [])
    .filter('join', function() {
        return function(list, token) {
            return (list||[]).join(token);
        }
    })

    .filter('pluck', function() {
        function getProperty(obj, prop) {
            return prop.split('.')
                .reduce(function (m, i) {
                    return m && typeof m === 'object' ? m[i] : null;
                }, obj);
        }

        function pluck(objects, propertiesString) {
            var results = [],
                properties,
                propsLn;

            if (Array.isArray(objects)) {
                properties = propertiesString.split('|');

                propsLn = properties.length;

                if (propsLn > 0) {
                    objects.forEach(function (obj) {
                        var property,
                            val,
                            i;

                        for (i = 0; i < propsLn; i++) {
                            property = properties[i].trim();

                            val = getProperty(obj, property);

                            if (val) {
                                if (Array.isArray(val)) {
                                    results = results.concat(val);
                                } else {
                                    results.push(val);
                                }

                                break;
                            }
                        }
                    });
                }
            }

            return results;
        }

        return function(objects, property) {
            return pluck(objects, property);
        }
    });