code: function checkSpacingBefore(token, pattern) {
              checkMethodMap[token.value].before(token, pattern || PREV_TOKEN);
          }
docs: Reports a given token if usage of spacing followed by the token is
  invalid.
  
  @param {Token} token - A token to report.
  @param {RegExp|undefined} pattern - Optional. A pattern of the previous
  token to check.
  @returns {void}