Enhancement: remove workaround for jest's handling of circular structures

[43081j]

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 rule list and found no rules that match my proposal.
• I have read the FAQ and my problem is not listed.

Relevant Package

rule-tester

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).

Description

typescript-eslint/packages/rule-tester/src/RuleTester.ts

Lines 228 to 229 in f30a20e

	// This nonsense is a workaround for https://github.com/jestjs/jest/issues/14840
	// see also https://github.com/typescript-eslint/typescript-eslint/issues/8942

It seems jest fixed this on their end now.

We should add a test case to prove this is true and remove the workaround code if it is.

Additional Info

No response

[kirkwaiblinger]

It seems jest fixed this on their end now.

From the jest issue, it sounds like not in v29, though, right? And 30 isn't released?

We should add a test case to prove this is true and remove the workaround code if it is.

The motivation for us adding this in the first place was just to be able to develop within the typescript-eslint repo, see #8942. So based on that I'd think we can just remove it, now that we've dropped jest internally (yay!). But I guess it does raise the question whether downstream consumers of the rule tester that use jest would be impacted 🤔

[43081j]

that was my thought too. since its in rule tester itself, maybe this also affects some end user somewhere? 😬

i suppose they might get worse errors if they're on older jest?

[kirkwaiblinger]

Makes sense 👍

they might get worse errors if they're on older jest?

To nitpick - this problem is present in the latest stable release of jest (v29), not older versions. v30 is only available as an alpha. So we definitely can't remove this workaround yet if we're concerned about the impact on downstream jest users.

[kirkwaiblinger]

I'm not too bothered if we just rip it out anyway, since jest is... jest. But there's no need to bother writing a test then 🤷‍♂

[JoshuaKGoldberg]

Blurgh yeah I hadn't noticed the fix wasn't released yet. Marking as blocked on Jest 30 going stable.

I don't know how long we'd want to wait after that. A lot of users will be stuck on Jest <30 for a while by the nature of major versions + breaking changes. And even though we just moved to Vitest (whoo!) Jest still has a huge number of users...