const reTranslate = /((^|\s)translate(3d|X)?\()(\-?[\d]+)/;
const reSkew = /((^|\s)skew(x|y)?\()\s*(\-?[\d]+)(deg|rad|grad)(,\s*(\-?[\d]+)(deg|rad|grad))?/;

/**
 * This function ensures that `style` supports both ltr and rtl directions by
 * checking `styleConstants` in `muiTheme` and replacing attribute keys if
 * necessary.
 */
export default function rtl(muiTheme) {
  if (muiTheme.isRtl) {
    return (style) => {
      const flippedAttributes = {
        // Keys and their replacements.
        right: 'left',
        left: 'right',
        marginRight: 'marginLeft',
        marginLeft: 'marginRight',
        paddingRight: 'paddingLeft',
        paddingLeft: 'paddingRight',
        borderRight: 'borderLeft',
        borderLeft: 'borderRight',
      };

      const newStyle = {};

      Object.keys(style).forEach(function(attribute) {
        let value = style[attribute];
        let key = attribute;

        if (flippedAttributes.hasOwnProperty(attribute)) {
          key = flippedAttributes[attribute];
        }

        switch (attribute) {
          case 'float':
          case 'textAlign':
            if (value === 'right') {
              value = 'left';
            } else if (value === 'left') {
              value = 'right';
            }
            break;

          case 'direction':
            if (value === 'ltr') {
              value = 'rtl';
            } else if (value === 'rtl') {
              value = 'ltr';
            }
            break;

          case 'transform':
            let matches;
            if ((matches = value.match(reTranslate))) {
              value = value.replace(matches[0], matches[1] + (-parseFloat(matches[4])) );
            }
            if ((matches = value.match(reSkew))) {
              value = value.replace(matches[0], matches[1] + (-parseFloat(matches[4])) + matches[5] +
                matches[6] ? `, ${(-parseFloat(matches[7])) + matches[8]}` : ''
              );
            }
            break;

          case 'transformOrigin':
            if (value.indexOf('right') > -1) {
              value = value.replace('right', 'left');
            } else if (value.indexOf('left') > -1) {
              value = value.replace('left', 'right');
            }
            break;
        }

        newStyle[key] = value;
      });

      return newStyle;
    };
  }
}


@@ -1506,16 +1506,47 @@
 sform':%0A
+            if (!value) break;%0A
         
@@ -2036,24 +2036,55 @@
 ormOrigin':%0A
+            if (!value) break;%0A
             

Check for nulls