code: function checkForIrregularWhitespace(node) {
              const sourceLines = sourceCode.lines;
  
              sourceLines.forEach((sourceLine, lineIndex) => {
                  const lineNumber = lineIndex + 1;
                  let match;
  
                  while ((match = IRREGULAR_WHITESPACE.exec(sourceLine)) !== null) {
                      const location = {
                          line: lineNumber,
                          column: match.index
                      };
  
                      errors.push({ node, message: "Irregular whitespace not allowed.", loc: location });
                  }
              });
          }
docs: Checks the program source for irregular whitespace
  @param {ASTNode} node The program node
  @returns {void}
  @private