src/language-js/comments.js/handleSwitchDefaultCaseComments
function handleSwitchDefaultCaseComments({
  comment,
  enclosingNode,
  followingNode,
}) {
  if (
    !enclosingNode ||
    enclosingNode.type !== "SwitchCase" ||
    enclosingNode.test
  ) {
    return false;
  }

  if (followingNode.type === "BlockStatement" && isLineComment(comment)) {
    addBlockStatementFirstComment(followingNode, comment);
  } else {
    addDanglingComment(enclosingNode, comment);
  }

  return true;
}