Question: how do I supply arguments to the style function?

[zkamvar]

I get super frustrated by the reindentation of comments, so I usually like to turn that off, but I cannot figure out how to pass the option reindentation = NULL to the pre-commit hook. I've tried tidyverse_style(reindentation = NULL) with no luck. Any advice?

style-files..............................................................Failed                                       
- hook id: style-files                                                                                                
- exit code: 1                                                                                                        
                                                                                                                      
Styling  2  files:                                                                                                    
 --style_fun=tidyverse_style(reindention = NULL) Error: --style_fun=tidyverse_style(reindention = NULL) is not an R, R
md or Rnw file                                                                                                        
Backtrace:                                                                                                            
    █                                                                                                                 
 1. └─styler::style_file(...)                                                                                         
 2.   └─styler:::transform_files(path, transformers, include_roxygen_examples)                                        
 3.     └─purrr::map_lgl(files, transform_file, fun = transformer, max_char_path = max_char)                          
 4.       └─styler:::.f(.x[[i]], ...)                                                                                 
 5.         └─styler:::transform_code(path, fun = fun, ...)                                                           
Execution halted       

[lorenzwalthert]

Thanks for raising this: Indeed, {precommit} currently does not allow you to use non-default arguments for the transformer because you can only pass a style function, not a transformer function. We should fix this and depreciate the use of --style_fun in favour of --transformer_fun and make it (more) consistent with the Addin in the {styler} package.

Context:

That's the way to specify the reindention with styler without precommit.

text <- '
call(
# no
)'

style_text(
  text, 
  transformers = styler::tidyverse_style(reindention = specify_reindention(""))
)

Now see the docs

  args: [--style_pkg=<styler>, --style_fun=<tidyverse_style>]

and note that style_fun takes the name of a transformer, not what it evaluates to when it's called, i.e. tidyverse_style, not tidyverse_style().

[lorenzwalthert]

So I'd like to allow:

  args: [--style_pkg=styler, --style_transformers='tidyverse_style(reindention = specify_reindention("")']

[lorenzwalthert]

I no longer think the proposed API was a good idea, in particular because of problems in parsing quotes on windows, see #195. https://github.com/lorenzwalthert/test-docopt.

I think we should make a more CLI-like interface and use key value pairs, so we can specify args like this:

  args: [--style_pkg=styler, --style_fun=tidyverse_style, --scope=spaces]

We can hardcode the args (but this would limit third-party style guides), or try to pass key-value pairs and have docopt parsing them.
Let's see if docopt want's to implement this or if we have to do a little work ourself to make it work flexibly: docopt/docopt.R#43

An alternative is to use a styler config file as proposed in r-lib/styler#319.

[lorenzwalthert]

Better late than never @zkamvar. You should now be able to use styler as you wanted:

  id: style-files
  args: [--scope=spaces, --reindention=specify_reindention('#')]

To not indent comments at all. For this to work until we create a new release (not CRAN, just hooks), you must set rev: in your config file to 57b54fb or something more recent. Let me know if it works.