@oat-sa/tao-item-runner-qti/dist/scoring/processor/expressions/randomInteger.js

TAO QTI Item Runner modules

define(['lodash', 'taoQtiItem/scoring/processor/errorHandler'], function (_, errorHandler) { 'use strict';

    _ = _ && Object.prototype.hasOwnProperty.call(_, 'default') ? _['default'] : _;
    errorHandler = errorHandler && Object.prototype.hasOwnProperty.call(errorHandler, 'default') ? errorHandler['default'] : errorHandler;

    /*
     * This program is free software; you can redistribute it and/or
     * modify it under the terms of the GNU General Public License
     * as published by the Free Software Foundation; under version 2
     * of the License (non-upgradable).
     *
     * This program is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with this program; if not, write to the Free Software
     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
     *
     * Copyright (c) 2015-2019 (original work) Open Assessment Technlogies SA (under the project TAO-PRODUCT);
     *
     */

    /**
     * Correct expression
     * @type {ExpressionProcesssor}
     * @exports taoQtiItem/scoring/processor/expressions/randomInteger
     */
    var randomIntegerProcessor = {
        /**
         * Process the expression
         * @returns {ProcessingValue} the value from the expression
         */
        process: function () {
            var range;
            var min = this.preProcessor.parseValue(this.expression.attributes.min, 'integerOrVariableRef');
            var max = this.preProcessor.parseValue(this.expression.attributes.max, 'integerOrVariableRef');
            var step =
                typeof this.expression.attributes.step !== 'undefined'
                    ? this.preProcessor.parseValue(this.expression.attributes.step, 'integerOrVariableRef')
                    : 1;

            var result = {
                cardinality: 'single',
                baseType: 'integer'
            };

            //verfiy attributes
            if (_.isNaN(min) || !_.isFinite(min)) {
                min = 0;
            }
            if (_.isNaN(max) || !_.isFinite(max)) {
                return errorHandler.throw(
                    'scoring',
                    new Error('The max value of a randomInteger expresssion should be a finite integer.')
                );
            }

            if (min > max) {
                return errorHandler.throw(
                    'scoring',
                    new Error('Come on! How am I supposed to generate a random number from a negative range : min > max')
                );
            }

            if (_.isNaN(step) || !_.isFinite(step)) {
                step = 1;
            }

            //get the random value
            if (step !== 1) {
                range = _.range(min, max, step);
                if (!range.includes(max)) {
                    range.push(max);
                }
                result.value = _.sample(range);
            } else {
                result.value = _.random(min, max);
            }

            return result;
        }
    };

    return randomIntegerProcessor;

});