anchor.diff:      tab.addClass('selected');
     };
   
  -  const $tabFilenames = $('.tab-filenames');
  +  const setupCurrentFilenameTab = () => {
  +    const $currentFilenameTab = $('<div>', {
  +      class:'tab filename',
  +         id:'current_filename',
  +       text:'readme.txt'
  +    });
  +    $tabFilenames.append($currentFilenameTab);
  +    setupTabFilenameClickHandler($currentFilenameTab);
  +  };
  +
  +  const setupOutputTabs = () => {
  +    outputTabNames.forEach(filename => {
  +      const $div = $('<div>', {
  +          class: 'tab filename',
  +             id: `radio_${filename}`,
  +           text: filename
  +      });
  +      $tabFilenames.append($div);
  +      setupTabFilenameClickHandler($div);
  +    });
  +  };
   
     const setupTabFilenameClickHandler = (div) => {
       div.click(() => {
  
positive.code:     });
    };
  
    outputTabNames.forEach(filename => {
      const $div = $('<div>', {
          class: 'tab filename',
             id: `radio_${filename}`,
           text: filename
      });
      $tabFilenames.append($div);
      setupTabFilenameClickHandler($div);
    });
  
    const $currentFilenameTab = $('<div>', {
      class:'tab filename',
         id:'current_filename',
       text:'readme.txt'
    });
    $tabFilenames.append($currentFilenameTab);
    setupTabFilenameClickHandler($currentFilenameTab);
  
  });
  </script>
  
negative.code: 'use strict';
  $(() => {
  
    const $tabFilenames = $('.tab-filenames');
    const outputTabNames = ['stdout','stderr','status'];
  
    cd.isOutputFile = filename => outputTabNames.includes(filename);
  