trotzig/diffux

define([
    "../core",
    "../var/indexOf",
    "./var/rneedsContext",
    "../selector"
], function( jQuery, indexOf, rneedsContext ) {

var risSimple = /^.[^:#\[\.,]*$/;

// Implement the identical functionality for filter and not
function winnow( elements, qualifier, not ) {
    if ( jQuery.isFunction( qualifier ) ) {
        return jQuery.grep( elements, function( elem, i ) {
            /* jshint -W018 */
            return !!qualifier.call( elem, i, elem ) !== not;
        });

    }

    if ( qualifier.nodeType ) {
        return jQuery.grep( elements, function( elem ) {
            return ( elem === qualifier ) !== not;
        });

    }

    if ( typeof qualifier === "string" ) {
        if ( risSimple.test( qualifier ) ) {
            return jQuery.filter( qualifier, elements, not );
        }

        qualifier = jQuery.filter( qualifier, elements );
    }

    return jQuery.grep( elements, function( elem ) {
        return ( indexOf.call( qualifier, elem ) >= 0 ) !== not;
    });
}

jQuery.filter = function( expr, elems, not ) {
    var elem = elems[ 0 ];

    if ( not ) {
        expr = ":not(" + expr + ")";
    }

    return elems.length === 1 && elem.nodeType === 1 ?
        jQuery.find.matchesSelector( elem, expr ) ? [ elem ] : [] :
        jQuery.find.matches( expr, jQuery.grep( elems, function( elem ) {
            return elem.nodeType === 1;
        }));
};

jQuery.fn.extend({
    find: function( selector ) {
        var i,
            len = this.length,
            ret = [],
            self = this;

        if ( typeof selector !== "string" ) {
            return this.pushStack( jQuery( selector ).filter(function() {
                for ( i = 0; i < len; i++ ) {
                    if ( jQuery.contains( self[ i ], this ) ) {
                        return true;
                    }
                }
            }) );
        }

        for ( i = 0; i < len; i++ ) {
            jQuery.find( selector, self[ i ], ret );
        }

        // Needed because $( selector, context ) becomes $( context ).find( selector )
        ret = this.pushStack( len > 1 ? jQuery.unique( ret ) : ret );
        ret.selector = this.selector ? this.selector + " " + selector : selector;
        return ret;
    },
    filter: function( selector ) {
        return this.pushStack( winnow(this, selector || [], false) );
    },
    not: function( selector ) {
        return this.pushStack( winnow(this, selector || [], true) );
    },
    is: function( selector ) {
        return !!winnow(
            this,

            // If this is a positional/relative selector, check membership in the returned set
            // so $("p:first").is("p:last") won't return true for a doc with two "p".
            typeof selector === "string" && rneedsContext.test( selector ) ?
                jQuery( selector ) :
                selector || [],
            false
        ).length;
    }
});

});