[BUG] exceljs throws an error "Invalid range in character set" in IE11 due to the lib "xmlchars"

🐛 Bug Report

Lib version: 3.8.2

Steps To Reproduce

1. In IE11

require('regenerator/runtime');
const Excel = require('exceljs/dist/es5/exceljs.bare');

1. Open the page that uses exceljs in IE11

The expected behaviour:

exceljs should work fine in IE11

Possible solution (optional, but very helpful):

The root cause is that exceljs uses saxes that uses xmlchars. And xmlchars uses regular expressions with the unicode flag (“u”) that cannot work in IE (so an error “Invalid range in character set” is thrown)

new RegExp(“^[”+t.NAME_START_CHAR+“]$”,“u”)

[alubbe]

Thanks for reporting this. As per https://github.com/exceljs/exceljs/pull/1193, you’ll need to polyfill unicode support in IE11, for example like this (before requiring exceljs):

const rewritePattern = require('regexpu-core');
const {generateRegexpuOptions} = require('@babel/helper-create-regexp-features-plugin/lib/util');

const {RegExp} = global;
try {
  new RegExp('a', 'u');
} catch (err) {
  global.RegExp = function(pattern, flags) {
    if (flags && flags.includes('u')) {
      return new RegExp(rewritePattern(pattern, flags, generateRegexpuOptions({flags, pattern})));
    }
    return new RegExp(pattern, flags);
  };
  global.RegExp.prototype = RegExp;
}

[alubbe]

The above fixed the issue on my windows laptop running IE11