Solution to Code Challenge 7 from "Refactoring Tweaks Workbook"

code-challenge-7.js

/* Code Challenge 7, from “Refactoring Tweaks Workbook” by Tonya Mork ( 2016, LeanPub (https://leanpub.com/littlegreenbookofrefactoringtweaks-workbook) ). */  

/***************************************************
 *
 * Original code to be refactored.
 *
 **************************************************/

window.PluginName = (function(window, document, $, undefined){
	'use strict';

	var plugin = {
		..
	}
	
	..

	plugin.toggleCheckBoxes = function( event ) {
		event.preventDefault();
		var $this = $( this );
		var $multicheck = $this.closest( '.plugin-td' ).find( 'input[type=checkbox]:not([disabled])' );

		// If the button has already been clicked once...
		if ( $this.data( 'checked' ) ) {
			// clear the checkboxes and remove the flag
			$multicheck.prop( 'checked', false );
			$this.data( 'checked', false );
		}
		// Otherwise mark the checkboxes and add a flag
		else {
			$multicheck.prop( 'checked', true );
			$this.data( 'checked', true );
		}
	};
	..
	return plugin;

})(window, document, jQuery);

/***************************************************
 *
 * Refactored Code
 *
 **************************************************/

window.PluginName = (function(window, document, $, undefined){
	'use strict';

	var plugin = {
		..
	}
	
	..

	plugin.toggleCheckBoxes = function( event ) {
		event.preventDefault();
		var $this = $( this );
		var $multicheck = $this.closest( '.plugin-td' ).find( 'input[type=checkbox]:not([disabled])' );


		if ( plugin.multiCheckIsChecked() )  {
			$multicheck.prop( 'checked', false );
			$this.data( 'checked', false );
		}

		if ( ! plugin.multiCheckIsChecked() ) {
			$multicheck.prop( 'checked', true );
			$this.data( 'checked', true );
		}
	};

   plugin.multiCheckIsChecked = function() {
    	if ( $multicheck.is( $this.data( 'checked' ) ) );
        return true;
  };
	..
	return plugin;

})(window, document, jQuery);