text: // Copyright 2014-2020, University of Colorado Boulder
  
  /**
   * Step backward button.
   *
   * @author Chris Malley (PixelZoom, Inc.)
   */
  
  import merge from '../../../phet-core/js/merge.js';
  import stepBackwardSoundPlayer from '../../../tambo/js/shared-sound-players/stepBackwardSoundPlayer.js';
  import sceneryPhet from '../sceneryPhet.js';
  import StepButton from './StepButton.js';
  
  class StepBackwardButton extends StepButton {
  
    /**
     * @param {Object} [options]
     */
    constructor( options ) {
  
      assert && assert( !options || !options.direction, 'StepBackwardButton sets direction' );
      options = merge( {
        direction: 'backward',
        soundPlayer: stepBackwardSoundPlayer
      }, options );
  
      super( options );
    }
  }
  
  sceneryPhet.register( 'StepBackwardButton', StepBackwardButton );
  export default StepBackwardButton;