Support TS config files

[polyzen]

ESLint 9.9.0 was just released with support for TS config files:
eslint/eslint#18134

[polyzen]

Not sure if it's as simple as adding eslint.config.ts, eslint.config.mts, and eslint.config.cts to https://github.com/microsoft/vscode-eslint/blob/release/3.0.10/server/src/eslint.ts#L800

Edit: For the VS Code client these need to be updated (seems they're also missing .mjs and .cjs?):
https://github.com/microsoft/vscode-eslint/blob/release/3.0.10/client/src/client.ts#L140
https://github.com/microsoft/vscode-eslint/blob/release/3.0.10/client/src/client.ts#L424

[polyzen]

Need also to at least pass --flag unstable_ts_config, but not having success using a TS config with just ESLint myself yet.
https://eslint.org/docs/latest/use/configure/configuration-files#typescript-configuration-files

[hyoban]

You can add the following settings:

{
  "eslint.options": {
    "flags": ["unstable_ts_config"]
  }
}

eslint.options: options to configure how ESLint is started using either the ESLint class API or the CLIEngine API.

options.flags (string[])
Default is []. The feature flags to enable for this instance.

• https://eslint.org/docs/latest/integrate/nodejs-api#parameters
• https://github.com/Microsoft/vscode-eslint#settings-options

[dbaeumer]

I added mjs and cjs to the watcher pattern. With the ts I would like to wait to see where the feature in eslint is heading to.

[nzakas]

@dbaeumer what questions can I answer about this feature for you?

(In general, feel free to reach out via GitHub discussion or Discord if you're ever blocked waiting for info about what ESLint is doing.)

[dbaeumer]

@nzakas my biggest question is currently why this is in ESLint since NodeJS itself added experimental support for this: https://nodejs.org/api/typescript.html#type-stripping

[nzakas]

@dbaeumer because ESLint needs to run on multiple versions of Node.js, some of which don't have experimental support, as well as Bun and Deno. Once TypeScript support is built into Node.js as stable, and we are able to move off of support for older versions, we can remove the jiti dependency.

[dbaeumer]

@gorstak17 please open a fresh issue for your problem, best with a GitHub repository I can clone with a minimal repro case that demos the problem you are seeing. This being said, please ensure that ESLint works correctly in the terminal before file the issue.