/** * Tests class member visibility (public, private, protected) * * Copyright (C) 2010 Mike Gerwitz * * This file is part of ease.js. * * ease.js is free software: you can redistribute it and/or modify it under the * terms of the GNU Lesser General Public License as published by the Free * Software Foundation, either version 3 of the License, or (at your option) * any later version. * * 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 Lesser General Public License * for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program. If not, see . * * @author Mike Gerwitz * @package test */ var common = require( './common' ), assert = require( 'assert' ), Class = common.require( 'class' ), pub = 'foo', prot = 'bar', priv = 'baz', pubf = function() { return pub; }, protf = function() { return prot; }, privf = function() { return priv; }, // new anonymous class instance foo = Class.extend( { 'public pub': pub, 'protected peeps': prot, 'private parts': priv, 'public pubf': pubf, 'protected protf': protf, 'private privf': privf, 'public getProp': function( name ) { // return property, allowing us to break encapsulation for // protected/private properties (for testing purposes) return this[ name ]; }, /** * Allows us to set a value from within the class */ 'public setValue': function( name, value ) { this[ name ] = value; }, })(); /** * Public members are the only members added to the instance's prototype to be * accessible externally */ ( function testPublicMembersAreAccessbileExternally() { assert.equal( foo.pub, pub, "Public properties are accessible via public interface" ); assert.equal( foo.pubf(), pub, "Public methods are accessible via public interface" ); } )(); /** * For reasons that are discussed in the next test (writing to public * properties), we need to make sure public members are available internally. * Actually, we don't need to test public methods, really, but it's in there for * good measure. Who knows what bugs may be introduced in the future. * * This ensures that the getter is properly proxying the value to us. */ ( function testPublicMembersAreAccessibleInternally() { assert.equal( foo.getProp( 'pub' ), pub, "Public properties are accessible internally" ); assert.equal( foo.getProp( 'pubf' )(), pub, "Public methods are accessible internally" ); } )(); /** * This may sound like an odd test, but it's actually very important. Due to how * private/protected members are implemented, it compromises public members. In * fact, public members would not work internally without what is essentially a * proxy via setters. * * This test is to ensure that the setter is properly forwarding writes to the * object within the prototype chain containing the public values. Otherwise, * setting the value would simply mask it in the prototype chain. The value * would appear to have changed internally, but when accessed externally, the * value would still be the same. That would obviously be a problem ;) */ ( function testPublicPropertiesAreWritableInternally() { var val = 'moomookittypoo'; // start by setting the value foo.setValue( 'pub', val ); // we should see that change internally... assert.equal( foo.getProp( 'pub' ), val, "Setting the value of a public property internally should be " + "observable /internally/" ); // ...as well as externally assert.equal( foo.pub, val, "Setting the value of a public property internally should be " + "observable /externally/" ); } )(); ( function testProtectedAndPrivateMembersAreNotAccessibleExternally() { assert.equal( foo.peeps, undefined, "Protected properties are inaccessible via public interface" ); assert.equal( foo.parts, undefined, "Private properties are inaccessible via public interface" ); assert.equal( foo.protf, undefined, "Protected methods are inaccessible via public interface" ); assert.equal( foo.privf, undefined, "Private methods are inaccessible via public interface" ); } )(); /** * Protected members should be accessible from within class methods */ ( function testProtectedMembersAreAccessibleInternally() { assert.equal( foo.getProp( 'peeps' ), prot, "Protected properties are available internally" ); // invoke rather than checking for equality, because the method may be // wrapped assert.equal( foo.getProp( 'protf' )(), prot, "Protected methods are available internally" ); } )();