Frequently asked question for developers

Let's collect some questions a lot of Nushell contributors have.

Let's keep the answers concise and up to date (or general enough) to remain relevant

How do I properly test my feature or bugfix?

TODO (Probably fork out into its own file)

Approximate flow:

Are you reporting the error in the parser/static checking phase?
- Use nu_protocol::ParseError variants
- Follow the logic used in the context as we need to collect multiple errors for a good IDE experience
Pick the right nu_protocol::ShellError variant
- Does a matching existing variant fit your need? (go to references of the ShellError variant for inspiration)
- Check what context the miette macros add during formatting! (go to definition of ShellError)
- If it is a one-of specific error, consider using a generic variant
- Else add a new class of errors
  - add the necessary Span information
  - general shared error text, to inform and point to a resolution
  - dynamic information gathered from the error site
  - Don't use a tuple enum variant, named structs going forward only!
Are you in a command?
- return Err(ShellError::...) and you're done in a Command::run
Do you want to report a warning but not stop execution?
- NEVER println!, we can write to stderr if necessary but...
- good practice: nu_protocol::report_error::report_error or report_error_new
  - depending on whether you have access to a StateWorkingSet
- if only relevant to in the field debugging: log-crate macros.

TODO

TODO