How do I hint a filetype to rome?

[UtkarshVerma]

When working with files without a specific extension, e.g. .prettierrc. rome does not format it because it's an unknown extension. Is there any way I can force rome to format the passed file as a specific filetype, like JSON?

[ematipico]

Not at the moment, but you can work around it:

cat .prettierrc | rome format --stdin-file-path=file.json > .prettierrc

[juliankasimir]

@UtkarshVerma Maybe the question is aimed at a somewhat general case, but in the case of Prettier (or Eslint) you can also give the file the appropriate file extension:
like .prettierrc.json, .prettierrc.js, or prettier.config.js.

[UtkarshVerma]

For a personal project that works, but for contributing to open-source projects .prettierrc is mostly used, and I can't change the filetype.

[juliankasimir]

@UtkarshVerma Adding the extension was recommended in Stylelint, so we did the same for the other formatting and linting files in our project. But if that doesn't work in your case, then the idea might be as @ematipico described above. You could possibly include this in the package.json as a normal script or if you like with conc, or lintstaged file.

Citation:

The .stylelintrc file (without extension) can be in JSON or YAML format. We recommend adding an extension to help your editor provide syntax checking and highlighting.

[ematipico]

For a personal project that works, but for contributing to open-source projects .prettierrc is mostly used, and I can't change the filetype.

I'd recommend suggesting to the people that own projects with extensionless files to move out from this practice. Files without extensions are not great for DX and create a lot of friction in the sphere of developer tools.

I don't know why and how this practice took place, but as a developer that makes developer tools, I assure you it's not easy to maintain! :)