text: const expandAbbreviatedValus = require('../../util/expand-abbreviated-values');
  const lengthPercentage = require('../../combies/length-percentage');
  const borderRadius = require('../border-radius');
  const optional = require('../../tools/optional');
  
  module.exports = stream => {
      const values = [];
  
      for (let i = 0; i < 4; i++) {
          const value = lengthPercentage(stream);
  
          if (value) {
              values.push(value);
          } else {
              break;
          }
      }
  
      if (!values.length) {
          return null;
      }
  
      const [top, right, bottom, left] = expandAbbreviatedValus(values);
      const radius = optional(stream, 'kw', 'round') &&
          borderRadius(stream) || null;
  
      return {
          type: 'inset',
          top, right, bottom, left,
          radius
      };
  };
  