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

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

My proposal is suitable for this project

• I believe my proposal would be useful to the broader TypeScript community (meaning it is not a niche proposal).

Link to the rule's documentation

https://typescript-eslint.io/rules/no-unnecessary-condition

Description

I constantly see LLMs generating code that checks variables by calling Array.isArray on them despite them being strictly typed as array. Adding logic intono-unnecessary-condition to detect these redundant calls would reduce code by avoiding unnecessary conditions and helps in reviewing AI generated code.

Fail

constitems:number[]=[1,2,3];if(Array.isArray(items)){console.log("items is an array");}

Pass

constitems:number[]|null=[1,2,3];if(Array.isArray(items)){console.log("items is an array");}

Additional Info

Maybe also include logic to detect unnecessaryitems instanceof Array?