ESLint - require let or const instead of var (no-var)

Question

How to disable the rule of discouraging the use of var and encouraging the use of const or let instead on ESlint?

Answer 1

In your package.json (assuming that is what you are using), include:

"eslintConfig": {
    "rules": {
        "no-var": 0
    }
}

no-var is the rule, and 0 sets the rule to "off".

If you're not using package.json, you can set the the same in an .eslintrc.js, or, on a per-file basis, include a comment at the top of the file /* eslint no-var: 0 */.

All this comes from the ESlint Configuration Documentation.

Answer 2

Extending the previous answer, all of these variants work for comments at the beginning of the block:

/* eslint no-var: off */
...

/* eslint no-var: */
...

/* eslint no-var: 0 */
...

Answer 3

The valid cases for using var are extremely limited, so it's good to consider disabling the no-var rule only on specific lines where's it's justified.

The //eslint-disable-line [RULE] comment can be used to turn off a single rule on a single line.

For example, if you're working with the Google Tracking dataLayer array:

declare global { var dataLayer: unknown[] }  //eslint-disable-line no-var
...
globalThis.dataLayer.push(args);

For more details:
https://eslint.org/docs/latest/use/configure/rules#disabling-rules