@oat-sa/tao-item-runner-qti/src/scoring/processor/expressions/operators/repeat.js

TAO QTI Item Runner modules

/*
 * 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);
 *
 */

/**
 * The repeat operator processor.
 * @see http://www.imsglobal.org/question/qtiv2p1/imsqti_infov2p1.html#element106215
 *
 * @author Bertrand Chevrier <bertrand@taotesting.com>
 */
import _ from 'lodash';
import errorHandler from 'taoQtiItem/scoring/processor/errorHandler';

/**
 * Process operands and returns repeat result.
 * @type {OperatorProcessor}
 * @exports taoQtiItem/scoring/processor/expressions/operators/repeat
 */
var repeatProcessor = {

    constraints: {
        minOperand: 0,
        maxOperand: -1,
        cardinality: ['single', 'ordered'],
        baseType: ['identifier', 'boolean', 'integer', 'float', 'string', 'point', 'pair', 'directedPair', 'duration', 'file', 'uri', 'intOrIdentifier']
    },

    operands: [],
    state: {},

    /**
     * @returns {?ProcessingValue} a single boolean
     */
    process: function() {

        var result = {
            cardinality: 'ordered',
            value: []
        };
        var filteredOperands;
        var value;

        var numberRepeats = this.preProcessor.parseValue(this.expression.attributes.numberRepeats, 'integerOrVariableRef');

        //if all one operands are null or no operands, then break and return null
        if (numberRepeats < 1 || _.every(this.operands, _.isNull) === true || this.operands.length === 0) {
            return null;
        }

        filteredOperands = _(this.operands).filter(_.isObject).value();

        if (Object.keys(_.countBy(filteredOperands, 'baseType')).length !== 1) {
            errorHandler.throw('scoring', new Error('operands must be of the same type'));
            return null;
        }

        result.baseType = this.operands[0].baseType;

        value = this.preProcessor.parseOperands(filteredOperands).value();

        while (numberRepeats-- > 0) {
            result.value.push(value);
        }

        result.value = _.flatten(result.value, true);

        return result;
    }
};

export default repeatProcessor;