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Issue Description

According to the docs, tseslint.config is a helper function that

1. gives you the ability to type-check your ESLint config, if you so desire, and
2. adds support for the extends property on config objects.
   Besides that, it should have no other effect.

However, another "hidden" difference, when using tseslint.config, is that it suppresses user-friendly error messages from ESLint.

For example, if a config object is undefined, ESLint returns:
TypeError: Config (unnamed): Unexpected undefined config at user-defined index 0.

but tseslint.config returns:
TypeError: Cannot destructure property 'extends' of 'configWithExtends' as it is undefined.
which is a less-helpful error.

Now, in an ideal world, TypeScript would report that a user had passed undefined to the function. However, I think there are several things to consider:

• Users may choose to keep their eslint.config.js in JavaScript, and not type-check it, while still using tseslint.config()
• Users may misspell a preset of an ESLint plugin, and that ESLint plugin might not provide TS type definitions, e.g. tseslint.config(eslintPlugin['nonexistent-preset']);
• No matter what happens on the TypeScript side, tseslint.config should not remove any functionality on the JavaScript side, since that's what the docs say.

Reproduction Repository Link

https://github.com/abrahamguo/repro/tree/undefined-config

Repro Steps

1. clone the repo
2. npm i
3. npx eslint -c tseslint.config.js . — compare with npx eslint .

Versions