code: function saveSelector (err, buffer, index, selectorArr) {
        let selector = selectorArr[index];
        if (selector === BODY_SELECTOR) {
          selector = DOCUMENT_SELECTOR;
        }
        const selectorProps = selectorMap[selector];
        const filePath = selectorProps.filePath;
        if (!selectorProps.exists) {
          return fs.copy(config.env.backstop + SELECTOR_NOT_FOUND_PATH, filePath);
        } else if (!selectorProps.isVisible) {
          return fs.copy(config.env.backstop + HIDDEN_SELECTOR_PATH, filePath);
        } else {
          if (err) {
            console.log('ChromyJS returned an unexpected error while attempting to capture a selector.', err);
            return new Error(err);
          }
          ensureDirectoryPath(filePath);
          return fs.writeFile(filePath, buffer);
        }
      }
docs: saveSelector: selectorArr will contain any valid selector (not body or viewport). If body *is* found in selector arr then it was originally DOCUMENT_SELECTOR -- and it will be reset back to DOCUMENT_SELECTOR -- this is because chromy takes a Document shot when BODY is used.