[#19] Began implementing method hiding (added warning for implicit hiding)
parent
bc3e879956
commit
db18a61d30
|
@ -28,9 +28,12 @@
|
|||
*/
|
||||
|
||||
var util = require( __dirname + '/util' ),
|
||||
warn = require( __dirname + '/warn' ),
|
||||
member_builder = require( __dirname + '/member_builder' ),
|
||||
propobj = require( __dirname + '/propobj' ),
|
||||
|
||||
Warning = warn.Warning,
|
||||
|
||||
/**
|
||||
* Class id counter, to be increment on each new definition
|
||||
* @type {number}
|
||||
|
@ -236,6 +239,8 @@ exports.build = function extend()
|
|||
|
||||
// build the various class components (xxx: this is temporary; needs
|
||||
// refactoring)
|
||||
try
|
||||
{
|
||||
buildMembers( props,
|
||||
class_id,
|
||||
base,
|
||||
|
@ -248,6 +253,19 @@ exports.build = function extend()
|
|||
return new_class.___$$svis$$;
|
||||
}
|
||||
);
|
||||
}
|
||||
catch ( e )
|
||||
{
|
||||
// intercept warnings /only/
|
||||
if ( e instanceof Warning )
|
||||
{
|
||||
warn.handle( e );
|
||||
}
|
||||
else
|
||||
{
|
||||
throw e;
|
||||
}
|
||||
}
|
||||
|
||||
// reference to the parent prototype (for more experienced users)
|
||||
prototype.___$$parent$$ = base.prototype;
|
||||
|
|
|
@ -24,6 +24,8 @@
|
|||
|
||||
var util = require( __dirname + '/util' ),
|
||||
|
||||
Warning = require( __dirname + '/warn' ).Warning,
|
||||
|
||||
fallback = util.definePropertyFallback(),
|
||||
visibility = [ 'public', 'protected', 'private' ];
|
||||
|
||||
|
@ -173,15 +175,6 @@ function validateMethod( keywords, prev_data, value, name )
|
|||
);
|
||||
}
|
||||
|
||||
// Can only override virtual methods. Abstract methods are considered to
|
||||
// be virtual.
|
||||
if ( !( prev_keywords[ 'virtual' ] || prev_keywords[ 'abstract' ] ) )
|
||||
{
|
||||
throw TypeError(
|
||||
"Cannot override non-virtual method '" + name + "'"
|
||||
);
|
||||
}
|
||||
|
||||
// do not allow overriding concrete methods with abstract
|
||||
if ( keywords[ 'abstract' ] && !( util.isAbstractMethod( prev ) ) )
|
||||
{
|
||||
|
@ -202,13 +195,25 @@ function validateMethod( keywords, prev_data, value, name )
|
|||
);
|
||||
}
|
||||
|
||||
// do not permit visibility de-escalation
|
||||
// do not permit visibility deescalation
|
||||
if ( prev_data.visibility < getVisibilityValue( keywords ) )
|
||||
{
|
||||
throw TypeError(
|
||||
"Cannot de-escalate visibility of method '" + name + "'"
|
||||
);
|
||||
}
|
||||
|
||||
// if redefining non-virtual method, the new method will "hide" the
|
||||
// parent's
|
||||
//
|
||||
// IMPORTANT: do this last, to ensure we throw errors before warnings
|
||||
if ( !( prev_keywords[ 'virtual' ] || prev_keywords[ 'abstract' ] ) )
|
||||
{
|
||||
throw Warning( Error(
|
||||
"Hiding method '" + name + "'; " +
|
||||
"use 'new' if intended, or 'override' to override instead"
|
||||
) );
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
|
|
@ -559,7 +559,7 @@ var common = require( './common' ),
|
|||
{
|
||||
Class(
|
||||
{
|
||||
'public baz': function() {},
|
||||
'virtual public baz': function() {},
|
||||
} ).extend( {
|
||||
'protected baz': function() {},
|
||||
} );
|
||||
|
@ -581,7 +581,7 @@ var common = require( './common' ),
|
|||
{
|
||||
Class(
|
||||
{
|
||||
'public baz': function() {},
|
||||
'virtual public baz': function() {},
|
||||
} ).extend( {
|
||||
'private baz': function() {},
|
||||
} );
|
||||
|
@ -603,7 +603,7 @@ var common = require( './common' ),
|
|||
{
|
||||
Class(
|
||||
{
|
||||
'protected baz': function() {},
|
||||
'virtual protected baz': function() {},
|
||||
} ).extend( {
|
||||
'private baz': function() {},
|
||||
} );
|
||||
|
|
|
@ -0,0 +1,80 @@
|
|||
/**
|
||||
* Tests hidden methods
|
||||
*
|
||||
* 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 <http://www.gnu.org/licenses/>.
|
||||
*
|
||||
* @author Mike Gerwitz
|
||||
* @package test
|
||||
*/
|
||||
|
||||
var common = require( './common' ),
|
||||
assert = require( 'assert' ),
|
||||
builder = common.require( 'class_builder' ),
|
||||
warn = common.require( 'warn' )
|
||||
;
|
||||
|
||||
|
||||
/**
|
||||
* Restores warning handler to the default
|
||||
*/
|
||||
function restoreWarningHandler()
|
||||
{
|
||||
warn.setHandler( warn.handlers.log );
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* If a non-virtual method is implicitly hidden (redefined without the 'new'
|
||||
* keyword), a warning should be provided. This will ensure that, should a
|
||||
* parent introduce a method that is already defined by a supertype, the
|
||||
* developer of the subtype is made aware of the issue.
|
||||
*/
|
||||
( function testThrowsWarningWhenHidingSuperMethod()
|
||||
{
|
||||
var thrown = false;
|
||||
|
||||
// mock the warning handler to ensure a warning is thrown
|
||||
warn.setHandler( function( e )
|
||||
{
|
||||
thrown = true;
|
||||
|
||||
assert.ok(
|
||||
( e.message.search( 'foo' ) !== -1 ),
|
||||
"Method hiding warning should contain method name"
|
||||
);
|
||||
} );
|
||||
|
||||
var Foo = builder.build(
|
||||
{
|
||||
// non-virtual method
|
||||
'public foo': function() {},
|
||||
} );
|
||||
|
||||
// hide the non-virtual method
|
||||
builder.build( Foo,
|
||||
{
|
||||
'public foo': function() {},
|
||||
} );
|
||||
|
||||
assert.equal( thrown, true, "No warning was thrown" );
|
||||
} )();
|
||||
|
||||
|
||||
// important, otherwise tests in combined file may fail
|
||||
restoreWarningHandler();
|
||||
|
|
@ -26,7 +26,10 @@ var common = require( './common' ),
|
|||
assert = require( 'assert' ),
|
||||
mb_common = require( __dirname + '/inc-member_builder-common' ),
|
||||
builder = common.require( 'member_builder' ),
|
||||
util = common.require( 'util' )
|
||||
util = common.require( 'util' ),
|
||||
|
||||
warn = common.require( 'warn' ),
|
||||
Warning = warn.Warning
|
||||
;
|
||||
|
||||
mb_common.funcVal = 'foobar';
|
||||
|
@ -72,43 +75,6 @@ mb_common.assertCommon();
|
|||
} )();
|
||||
|
||||
|
||||
/**
|
||||
* Unlike Java, PHP, Python and similar languages, methods in ease.js are *not*
|
||||
* virtual by default. In order to make them override-able, the 'virtual'
|
||||
* keyword must be specified for that method in the supertype.
|
||||
*
|
||||
* Therefore, let's ensure that non-virtual methods cannot be overridden.
|
||||
*/
|
||||
( function testCannotOverrideNonVirtualMethod()
|
||||
{
|
||||
mb_common.value = function() {};
|
||||
mb_common.buildMemberQuick();
|
||||
|
||||
try
|
||||
{
|
||||
// attempt to override (should throw exception; non-virtual)
|
||||
mb_common.buildMemberQuick( {}, true );
|
||||
}
|
||||
catch ( e )
|
||||
{
|
||||
// ensure we have the correct error
|
||||
assert.ok(
|
||||
e.message.search( 'virtual' ) !== -1,
|
||||
"Error message for non-virtual override should mention virtual"
|
||||
);
|
||||
|
||||
assert.ok(
|
||||
e.message.search( mb_common.name ) !== -1,
|
||||
"Method name should be provided in non-virtual error message"
|
||||
);
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
assert.fail( "Should not be permitted to override non-virtual methods" );
|
||||
} )();
|
||||
|
||||
|
||||
/**
|
||||
* Working off of what was said in the test directly above, we *should* be able
|
||||
* to override virtual methods.
|
||||
|
@ -143,10 +109,16 @@ mb_common.assertCommon();
|
|||
mb_common.buildMemberQuick( {}, true );
|
||||
|
||||
// attempt to override again (should fail)
|
||||
assert.throws( function()
|
||||
try
|
||||
{
|
||||
mb_common.buildMemberQuick( {}, true );
|
||||
}, TypeError, "Overrides are not declared as virtual by default" );
|
||||
}
|
||||
catch ( e )
|
||||
{
|
||||
return;
|
||||
}
|
||||
|
||||
assert.fail( "Overrides should not be declared as virtual by default" );
|
||||
} )();
|
||||
|
||||
|
||||
|
|
Loading…
Reference in New Issue