accessibility-developer-tools/src/js/AuditRules.js

This is a library of accessibility-related testing and utility code.

// Copyright 2012 Google Inc.
//
// 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.

goog.require('axs.AuditRule');

goog.provide('axs.AuditRules');

(function() {
    var auditRulesByName = {};
    var auditRulesByCode = {};

    /** @type {Object.<string, axs.AuditRule.Spec>} */
    axs.AuditRules.specs = {};

    /**
     * Instantiates and registers an audit rule.
     * If a conflicting rule is already registered then the new rule will not be added.
     * @param {axs.AuditRule.Spec} spec The object which defines the AuditRule to add.
     * @throws {Error} If the rule duplicates properties that must be unique.
     */
    axs.AuditRules.addRule = function(spec) {
        // create the auditRule before checking props as we can expect the constructor to perform the
        // first layer of sanity checking.
        var auditRule = new axs.AuditRule(spec);
        if (auditRule.code in auditRulesByCode)
            throw new Error('Can not add audit rule with same code: "' + auditRule.code + '"');
        if (auditRule.name in auditRulesByName)
            throw new Error('Can not add audit rule with same name: "' + auditRule.name + '"');
        auditRulesByName[auditRule.name] = auditRulesByCode[auditRule.code] = auditRule;
        axs.AuditRules.specs[spec.name] = spec;
    };

    /**
     * Gets the audit rule with the given name.
     * @param {string} name The name (or code) of an audit rule.
     * @return {axs.AuditRule}
     */
    axs.AuditRules.getRule = function(name) {
        return auditRulesByName[name] || auditRulesByCode[name] || null;
    };

    /**
     * Gets all registered audit rules.
     * @param {boolean=} opt_namesOnly If true then the result will contain only the rule names.
     * @return {Array.<axs.AuditRule>|Array.<string>}
     */
    axs.AuditRules.getRules = function(opt_namesOnly) {
        var ruleNames = Object.keys(auditRulesByName);
        if (opt_namesOnly)
            return ruleNames;
        return ruleNames.map(function(name) {
            return this.getRule(name);
        }, axs.AuditRules);
    };

    /**
     * Gets all registered audit rules which are not excluded by configuration.
     * @param {axs.AuditConfiguration} configuration Used to determine ignored rules.
     * @return {Array.<axs.AuditRule>}
     */
    axs.AuditRules.getActiveRules = function(configuration) {
        var auditRules;
        if (configuration.auditRulesToRun && configuration.auditRulesToRun.length > 0) {
            auditRules = configuration.auditRulesToRun;
        } else {
            auditRules = axs.AuditRules.getRules(true);
        }
        if (configuration.auditRulesToIgnore) {
            for (var i = 0; i < configuration.auditRulesToIgnore.length; i++) {
                var auditRuleToIgnore = configuration.auditRulesToIgnore[i];
                if (auditRules.indexOf(auditRuleToIgnore) < 0)
                    continue;
                auditRules.splice(auditRules.indexOf(auditRuleToIgnore), 1);
            }
        }
        return auditRules.map(axs.AuditRules.getRule);
    };
})();