feat: add require-compound-type-alias option to create an exception for x | null types

[gajus]

Most of the require-compound-type-alias errors that I get refer to explicit or NULL types, e.g.

type PoolContextType = {|
  +log: LoggerType,
  +poolId: string,
  +query: TaggedTemplateLiteralInvocationType | null
|};

In this case creating a separate type would have little added value.

[gajus]

CC @pnevyk In case this is relevant to you too.

[pnevyk]

It looks like an easy fix to me, something that can be a good first PR. If anyone is interested, the task is to enhance both visitor rules in this file to check if node.types.length == 2 and one of the nodes in node.types is of type "NullLiteralTypeAnnotation" if this option is enabled, and to update the rule schema.

@gajus If nobody takes this up, I will do it in (hopefully) near future in a free while.

[gajus]

🎉 This issue has been resolved in version 5.1.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀