Fix a failing effects test in IE; minor style changes in effects

src/css.js

@@ -285,12 +285,14 @@ if ( document.defaultView && document.defaultView.getComputedStyle ) {
 
 if ( document.documentElement.currentStyle ) {
 	currentStyle = function( elem, name ) {
-		var left, rsLeft,
+		var left, rsLeft, uncomputed,
 			ret = elem.currentStyle && elem.currentStyle[ name ],
 			style = elem.style;
 
-		if ( ret === null && style ) {
-			ret = style[ name ];
+		// Avoid setting ret to empty string here
+		// so we don't default to auto
+		if ( ret === null && style && (uncomputed = style[ name ]) ) {
+			ret = uncomputed;
 		}
 
 		// From the awesome hack by Dean Edwards

src/effects.js

@@ -20,11 +20,11 @@ jQuery.fn.extend({
 		var elem, display;
 
 		if ( speed || speed === 0 ) {
-			return this.animate( genFx("show", 3), speed, easing, callback);
+			return this.animate( genFx("show", 3), speed, easing, callback );
 
 		} else {
 			for ( var i = 0, j = this.length; i < j; i++ ) {
-				elem = this[i];
+				elem = this[ i ];
 
 				if ( elem.style ) {
 					display = elem.style.display;
@@ -38,8 +38,8 @@ jQuery.fn.extend({
 					// Set elements which have been overridden with display: none
 					// in a stylesheet to whatever the default browser style is
 					// for such an element
-					if ( display === "" && jQuery.css( elem, "display" ) === "none" ) {
-						jQuery._data(elem, "olddisplay", defaultDisplay(elem.nodeName));
+					if ( display === "" && jQuery.css(elem, "display") === "none" ) {
+						jQuery._data( elem, "olddisplay", defaultDisplay(elem.nodeName) );
 					}
 				}
 			}
@@ -47,13 +47,13 @@ jQuery.fn.extend({
 			// Set the display of most of the elements in a second loop
 			// to avoid the constant reflow
 			for ( i = 0; i < j; i++ ) {
-				elem = this[i];
+				elem = this[ i ];
 
 				if ( elem.style ) {
 					display = elem.style.display;
 
 					if ( display === "" || display === "none" ) {
-						elem.style.display = jQuery._data(elem, "olddisplay") || "";
+						elem.style.display = jQuery._data( elem, "olddisplay" ) || "";
 					}
 				}
 			}
@@ -67,12 +67,17 @@ jQuery.fn.extend({
 			return this.animate( genFx("hide", 3), speed, easing, callback);
 
 		} else {
-			for ( var i = 0, j = this.length; i < j; i++ ) {
-				if ( this[i].style ) {
-					var display = jQuery.css( this[i], "display" );
+			var elem, display,
+				i = 0,
+				j = this.length;
 
-					if ( display !== "none" && !jQuery._data( this[i], "olddisplay" ) ) {
-						jQuery._data( this[i], "olddisplay", display );
+			for ( ; i < j; i++ ) {
+				elem = this[i];
+				if ( elem.style ) {
+					display = jQuery.css( elem, "display" );
+
+					if ( display !== "none" && !jQuery._data( elem, "olddisplay" ) ) {
+						jQuery._data( elem, "olddisplay", display );
 					}
 				}
 			}
@@ -635,7 +640,6 @@ function defaultDisplay( nodeName ) {
 		var body = document.body,
 			elem = jQuery( "<" + nodeName + ">" ).appendTo( body ),
 			display = elem.css( "display" );
-
 		elem.remove();
 
 		// If the simple way fails,
@@ -663,7 +667,6 @@ function defaultDisplay( nodeName ) {
 			iframeDoc.body.appendChild( elem );
 
 			display = jQuery.css( elem, "display" );
-
 			body.removeChild( iframe );
 		}