> exceljs@4.2.0 lint C:\dev\exceljs.exceljs
> eslint --format node_modules/eslint-friendly-formatter .
...
(details clipped, see comment below)

Errors:
  24  http://eslint.org/docs/rules/no-mixed-operators
   9  http://eslint.org/docs/rules/no-underscore-dangle
   5  http://eslint.org/docs/rules/max-len
   2  http://eslint.org/docs/rules/semi
   2  http://eslint.org/docs/rules/quotes
   2  http://eslint.org/docs/rules/prefer-const
   2  http://eslint.org/docs/rules/no-await-in-loop
   1  http://eslint.org/docs/rules/no-restricted-globals
   1  http://eslint.org/docs/rules/no-trailing-spaces
   1  https://google.com/#q=import%2Fno-unresolved
   1  https://google.com/#q=node%2Fno-missing-require
   1  https://google.com/#q=import%2Fno-extraneous-dependencies
   1  https://google.com/#q=node%2Fno-extraneous-require

Warnings:
  1  http://eslint.org/docs/rules/prefer-destructuring

git clone https://github.com/exceljs/exceljs.git
cd exceljs
npm i
npm lint