code: function checkFunction(node) {
              const functionConfig = getConfigForFunction(node);
  
              if (functionConfig === "ignore") {
                  return;
              }
  
              const rightToken = sourceCode.getFirstToken(node, astUtils.isOpeningParenToken);
              const leftToken = sourceCode.getTokenBefore(rightToken);
              const hasSpacing = sourceCode.isSpaceBetweenTokens(leftToken, rightToken);
  
              if (hasSpacing && functionConfig === "never") {
                  context.report({
                      node,
                      loc: leftToken.loc.end,
                      message: "Unexpected space before function parentheses.",
                      fix: fixer => fixer.removeRange([leftToken.range[1], rightToken.range[0]])
                  });
              } else if (!hasSpacing && functionConfig === "always") {
                  context.report({
                      node,
                      loc: leftToken.loc.end,
                      message: "Missing space before function parentheses.",
                      fix: fixer => fixer.insertTextAfter(leftToken, " ")
                  });
              }
          }
docs: Checks the parens of a function node
  @param {ASTNode} node A function node
  @returns {void}