Before You File a Proposal Please Confirm You Have Done The Following...

• I have searched for related issues and found none that match my proposal.
• I have searched the current extension rule list and found no rules that match my proposal.
• I have read the FAQ and my problem is not listed.

My proposal is suitable for this project

• My proposal specifically checks TypeScript syntax, or it proposes a check that requires type information to be accurate.
• I believe my proposal would be useful to the broader TypeScript community (meaning it is not a niche proposal).

Link to the base rule

https://eslint.org/docs/latest/rules/block-spacing

Description

I believe the purpose of the base rule, applies for TS too

Fail

interface Shape {x: number}
interface Shape { x: number}
interface Shape {x: number }
interface Shape {x: number; y: number}

Pass

interface Shape { x: number }
interface Shape { x: number; y: number }

Additional Info

Actually, having a rule that rejects single line interface declarations could work too