Configuration file support

I think it would be valuable to support for some type of file that contains prettier’s config so that projects can check it in source control.

I can see 2 cases where this would be useful.

• Allow tools to know that the project is using prettier. I’d like to enable thing like format on save but I don’t want to reformat everyfile I touch on a project that doesn’t use prettier.
• Allow per project config to avoid the need to change options when changing projects or to have to create custom formating scripts.

Could be it’s own file (something like .editorconfig) or maybe part of package.json.

[jlongster]

We aim to be zero-config. For now at least, I am against this. The few existing config options only exist to help applying to existing projects, and should only be used if you really need to. We will see what happens over time, but for now I’ll point you to https://github.com/jlongster/prettier/issues/40

[ljharb]

The problem is that not everyone will adopt a tool like this all at once, thus the “generic format” for text needs to match the project’s existing conventions. Disallowing config will mean that adopting prettier is an all-or-nothing approach, unless the project just happens to already comply with the convention prettier chooses, which - for the exact reasons you mention that the ecosystem could benefit from this tool - will prevent adoption of it, on any larger scale.