Discussion: Syntax for controlling mixing of linter sources

[dgkf]

This is one of the more complex behaviors of the package. I'll start with background. There are a number of ways that linters can be added:

1. roxylint provides its own default linters (that follow the tidyverse style guide for documentation).
2. Other packages (eg roxytypes) can register linters as well. They'll be registered when they load or when roxytypes loads (if it wasn't already loaded)
3. Users may define their own linters.

So, given a tag (let's say @param), there might be some default value, some additional linters provided by other packages, and some user-defined linters.

With this, a user should be able to specify whether they want to add to or overwrite existing linters, and assert that new linters should or shouldn't be allowed on top of the ones they've defined.

For now, providing a linter always overwrites existing linters and NULL is used as a sentinel value that says "do not allow more linters for this tag".

However, this isn't very pretty, is a bit unintuitive, and does not provide the ability to add to existing linters. Instead, we might imagine a special constructor:

list(
  linters = list(
    param = roxytypes::linters(mask = FALSE, lock = FALSE,
      function(x, name, description, ...) {
        n_caps <- nchar(gsub("[^[:upper:]]", "", description))
        if (n_caps < nchar(description) / 2)
          warning("descriptions should be at least 50% CaPiTALiZeD")
      }
    )
  )
)

[danielinteractive]

Yeah special constructor also works well I guess.
Maybe in general, I wonder how much you could lean on the lintr package for semantics and syntax to simplify learning curve for users.

[dgkf]

A couple thoughts inspired by the lintr comparison

• tag-specific constructors might be nice so that you could do something like:

  list(linters = list(
    param = tidy_param(sentence_case = FALSE)
  ))

  This would be the equivalent to lintr's linters_with_defaults. These would be easy enough to add to just turn on-and-off specific default linters.
• I think we'd still want to be able to "lock" or "mask" existing linters
• The example above is an "advanced" usage. I already borrow from lintr's builtin defaults, so to mirror a more beginner-friendly usage that still uses the mask/lock wrapper, it could look something like:

  param = roxylint::linters(mask = FALSE, lock = FALSE,
    lint_sentence_case,
    lint_full_stop
  )

  I think this is about as straightforward as it could look since we still need to provide a linter style per-tag.
• Not sure if this is what you had in mind, but I think the .R config file styled after roxygen2 is much more user friendly than lintr's .dcf file since you get all the conveniences of your IDE for writing R code.

[danielinteractive]

Thanks @dgkf yeah that looks nice! Yes .R is better.