Question

Reading jQuery 1.8 test/unit/effects.js test, what is it trying to test here?

    var speeds = {
        'null speed' : null,
        'undefined speed': undefined,
        'false speed': false
    }

    // make sure passing bogus arguments doesn't change state var ?
    jQuery.each( speeds,
                 function( name, speed ) {
                     pass = true;
                     div.hide()
                         .show(speed)
                         .each( function() {
                                     if( this.style.display == 'none' ) {
                                         pass = false;
                                     }
                              });
                         ok( pass, 'Show with ' + name );
                 });

Answer 1

As the comment in the code states, it makes sure that passing invalid values to the .show() method won’t break it. That is, .show( null ), .show( undefined ) and .show( false ) all display the element even though the parameter is invalid.