[no-type-alias] Rule fails with "Unhandled in union types are not allowed." when encountering null

[mdouglass]

Repro

{
  "rules": {
    "@typescript-eslint/no-type-alias": [
      "error",
      {
        "allowAliases": "always",
        "allowCallbacks": "always",
        "allowLiterals": "in-unions-and-intersections",
        "allowMappedTypes": "always",
        "allowTupleTypes": "always",
      },
    ]
  }
}

export type Value = null | string | number

Expected Result
No errors

Actual Result
Unhandled in union types are not allowed.eslint@typescript-eslint/no-type-alias

Versions

package	version
@typescript-eslint/eslint-plugin	3.7.0
@typescript-eslint/parser	3.7.0
TypeScript	3.9.7
ESLint	7.5.0
node	14.6.0
npm	6.14.6

[bradzacher]

This is fixed by #2316. I accidentally introduced a regression in the AST.
This will be released tomorrow morning - you can try the canary tag on NPM in the meantime.

[mdouglass]

Awesome, thank you. I'll give it a try shortly.