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Mixin use method calls can now be chained

Syntatic sugar; could have previously extended explicitly and then mixed in.
perfodd
Mike Gerwitz 2014-03-05 23:42:48 -05:00
parent 8480d8f92c
commit 88713987e2
2 changed files with 41 additions and 0 deletions

View File

@ -403,6 +403,13 @@ function createUse( base, traits )
);
};
// syntatic sugar to avoid the aruduous and seemingly pointless `extend'
// call simply to mix in another trait
partial.use = function()
{
return partial.extend( {} ).use.apply( null, arguments );
};
return partial;
}

View File

@ -175,4 +175,38 @@ require( 'common' ).testCase(
this.assertOk( called_bar );
this.assertOk( called_baz );
},
/**
* This test ensures that we can mix in traits using the syntax
* C.use(T1).use(T2), and so on; this may be necessary to disambiguate
* overrides if T1 and T2 provide definitions for the same method (and
* so the syntax C.use(T1, T2) cannot be used). This syntax is also
* important for the concept of stackable traits (see
* LinearizationTest).
*
* Note that this differs from C.use(T1).use(T2).extend({}); we're
* talking about C.extend({}).use(T1).use(T2). Therefore, this can be
* considered to be syntatic sugar for
* C.use( T1 ).extend( {} ).use( T2 ).
*/
'Can chain use calls': function()
{
var T1 = this.Sut( { foo: function() {} } ),
T2 = this.Sut( { bar: function() {} } ),
C = null;
var Class = this.Class;
this.assertDoesNotThrow( function()
{
C = Class.extend( {} ).use( T1 ).use( T2 );
} );
// ensure that the methods were actually mixed in
this.assertDoesNotThrow( function()
{
C().foo();
C().bar();
} );
},
} );