277 lines
8.3 KiB
JavaScript
277 lines
8.3 KiB
JavaScript
/**
|
|
* Tests class interface implement method
|
|
*
|
|
* Copyright (C) 2010, 2011, 2013 Mike Gerwitz
|
|
*
|
|
* This file is part of GNU ease.js.
|
|
*
|
|
* ease.js 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, 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
require( 'common' ).testCase(
|
|
{
|
|
caseSetUp: function()
|
|
{
|
|
this.Class = this.require( 'class' );
|
|
this.Interface = this.require( 'interface' );
|
|
this.AbstractClass = this.require( 'class_abstract' );
|
|
|
|
// test with and without abstract keyword
|
|
this.Type = this.Interface.extend( {
|
|
'abstract foo': [],
|
|
} );
|
|
|
|
this.Type2 = this.Interface.extend( {
|
|
foo2: [],
|
|
} );
|
|
|
|
this.PlainFoo = this.Class.extend();
|
|
},
|
|
|
|
|
|
'Class exports contain implement method for no base class': function()
|
|
{
|
|
this.assertOk(
|
|
( this.Class.implement instanceof Function ),
|
|
"Class provides method to implement interfaces"
|
|
);
|
|
},
|
|
|
|
|
|
'Clsss object contains implement method for self as base': function()
|
|
{
|
|
this.assertOk(
|
|
( this.PlainFoo.implement instanceof Function ),
|
|
"Classes contain an implement() method"
|
|
);
|
|
},
|
|
|
|
|
|
'Can implement interface from an empty base': function()
|
|
{
|
|
var _self = this;
|
|
this.assertDoesNotThrow( function()
|
|
{
|
|
_self.Class.implement( _self.Type, _self.Type2 );
|
|
}, Error, "Class can implement interfaces" );
|
|
},
|
|
|
|
|
|
/**
|
|
* Initially, the implement() method returned an abstract class. However, it
|
|
* doesn't make sense to create a class without any actual definition (and
|
|
* there's other implementation considerations that caused this route to be
|
|
* taken). One wouldn't do "class Foo implements Type", and not provide any
|
|
* body.
|
|
*
|
|
* Therefore, implement() should return nothing useful until extend() is
|
|
* called on it.
|
|
*/
|
|
'Result of implement is not usable as a class': function()
|
|
{
|
|
var _self = this,
|
|
result = this.Class.implement( this.Type );
|
|
|
|
this.assertEqual(
|
|
( _self.Class.isClass( result ) ),
|
|
false,
|
|
"Result of implement operation on class is not usable as a Class"
|
|
);
|
|
},
|
|
|
|
|
|
/**
|
|
* As a consequence of the above, we must extend with an empty definition
|
|
* (base) in order to get our abstract class.
|
|
*/
|
|
'Abstract methods are copied into new class using empty base': function()
|
|
{
|
|
var Foo = this.AbstractClass.implement( this.Type, this.Type2 )
|
|
.extend( {} );
|
|
|
|
this.assertOk(
|
|
( ( Foo.prototype.foo instanceof Function )
|
|
&& ( Foo.prototype.foo2 instanceof Function )
|
|
),
|
|
"Abstract methods are copied into the new class prototype " +
|
|
"(empty base)"
|
|
);
|
|
},
|
|
|
|
|
|
'Can implement interface atop an existing class': function()
|
|
{
|
|
var _self = this;
|
|
|
|
this.assertDoesNotThrow( function()
|
|
{
|
|
_self.PlainFoo.implement( _self.Type, _self.Type2 );
|
|
}, Error, "Classes can implement interfaces" );
|
|
},
|
|
|
|
|
|
/**
|
|
* Ensure the same system mentioned above also applies to the extend()
|
|
* method on existing classes
|
|
*/
|
|
'Implementing interface atop existing class not usable by default':
|
|
function()
|
|
{
|
|
var result = this.PlainFoo.implement( this.Type );
|
|
|
|
this.assertEqual(
|
|
( this.Class.isClass( result ) ),
|
|
false,
|
|
"Result of implementing interfaces on an existing base is not " +
|
|
"usable as a Class"
|
|
);
|
|
},
|
|
|
|
|
|
'Abstract method copied into new class using existing base': function()
|
|
{
|
|
var PlainFoo2 = this.AbstractClass
|
|
.implement( this.Type, this.Type2 )
|
|
.extend( this.PlainFoo, {} );
|
|
|
|
this.assertOk(
|
|
( ( PlainFoo2.prototype.foo instanceof Function )
|
|
&& ( PlainFoo2.prototype.foo2 instanceof Function )
|
|
),
|
|
"Abstract methods are copied into the new class prototype " +
|
|
"(concrete base)"
|
|
);
|
|
},
|
|
|
|
|
|
/**
|
|
* Since interfaces can contain only abstract methods, it stands to
|
|
* reason that any class implementing an interface without providing any
|
|
* concrete methods should be abstract by default.
|
|
*/
|
|
'Classes implementing interfaces are considered abstract by default':
|
|
function()
|
|
{
|
|
var Foo = this.AbstractClass.implement( this.Type ).extend( {} );
|
|
|
|
this.assertEqual(
|
|
Foo.isAbstract(),
|
|
true,
|
|
"Classes that implements interface(s) are considered abstract if " +
|
|
"the implemented methods have no concrete implementations"
|
|
);
|
|
},
|
|
|
|
|
|
'Instances of classes are instances of their implemented interfaces':
|
|
function()
|
|
{
|
|
var Foo = this.AbstractClass.implement( this.Type, this.Type2 )
|
|
.extend( {} );
|
|
|
|
// concrete implementation so that we can instantiate it
|
|
var ConcreteFoo = Foo.extend(
|
|
{
|
|
'foo': function() {},
|
|
'foo2': function() {},
|
|
}),
|
|
|
|
concrete_inst = ConcreteFoo()
|
|
;
|
|
|
|
this.assertOk(
|
|
( concrete_inst.isInstanceOf( this.Type )
|
|
&& concrete_inst.isInstanceOf( this.Type2 )
|
|
),
|
|
"Instances of classes implementing interfaces are considered to " +
|
|
"be instances of the implemented interfaces"
|
|
);
|
|
|
|
this.assertEqual(
|
|
ConcreteFoo.isAbstract(),
|
|
false,
|
|
"Concrete implementations are not considered to be abstract"
|
|
);
|
|
},
|
|
|
|
|
|
/**
|
|
* Consider the following scenario:
|
|
*
|
|
* MyClass.implement( Type ).extend( MyOtherClass, {} );
|
|
*
|
|
* What the above is essentially saying is: "I'd like to extend MyClass by
|
|
* implementing Type. Oh, no, wait, I'd actually like it to extend
|
|
* MyOtherClass." That doesn't make sense! Likely, it's unintended. Prevent
|
|
* confusion and bugs. Throw an error.
|
|
*/
|
|
'Cannot specify parent after implementing atop existing class': function()
|
|
{
|
|
var PlainFoo2 = this.AbstractClass
|
|
.implement( this.Type, this.Type2 )
|
|
.extend( this.PlainFoo, {} );
|
|
|
|
this.assertThrows( function()
|
|
{
|
|
// should not be permitted
|
|
this.PlainFoo.implement( this.Type, this.Type2 )
|
|
.extend( PlainFoo2, {} );
|
|
},
|
|
Error,
|
|
"Cannot specify new parent for extend() when implementing from " +
|
|
"existing class"
|
|
);
|
|
},
|
|
|
|
|
|
/**
|
|
* Opposite of the above test. If a parent wasn't specified to begin with,
|
|
* then we're fine to specify it in extend().
|
|
*/
|
|
'Can specify parent if implementing atop empty class': function()
|
|
{
|
|
var _self = this;
|
|
|
|
this.assertDoesNotThrow(
|
|
function()
|
|
{
|
|
// this /should/ work
|
|
_self.AbstractClass.implement( _self.Type )
|
|
.extend( _self.PlainFoo, {} );
|
|
},
|
|
Error,
|
|
"Can specify parent for extend() when implementing atop an " +
|
|
"empty base"
|
|
);
|
|
},
|
|
|
|
|
|
/**
|
|
* If more than two arguments are given to extend(), then the developer
|
|
* likely does not understand the API. Throw an error to prevent some
|
|
* bugs/confusion.
|
|
*/
|
|
'Throws exception if extend contains too many arguments': function()
|
|
{
|
|
var _self = this;
|
|
|
|
this.assertThrows( function()
|
|
{
|
|
_self.Class.implement( _self.Type )
|
|
.extend( _self.PlainFoo, {}, 'extra' );
|
|
}, Error, "extend() after implementing accepts no more than two args" );
|
|
},
|
|
} );
|
|
|