New feature: style_book function

[jcrodriguez1989]

While I was trying to style the The R in Spark bookdown project from within RStudio, I noticed there was not a straightforward way to do it.
As the styler package has the useful style_pkg function, I thought it would be equally useful to have a style_book function.
Note: If PR accepted, I will work on some tests.

Some output:
Trying to use style_pkg on the bookdown project:

style_pkg(filetype = c(".R", ".Rmd", ".Rnw"))
## ────────────────────────────────────────
## Status	Count	Legend 
## ✔ 	0	File unchanged.
## ℹ 	0	File changed.
## ✖ 	0	Styling threw an error.
## ────────────────────────────────────────

Using style_book:

style_book()
## Styling  19  files:
##  ./analysis.Rmd                               ℹ 
##  ./appendix.Rmd                               ℹ 
##  ./clusters.Rmd                               ℹ 
##  ./connections.Rmd                            ⚠ 
##  ./contributing.Rmd                           ℹ 
##  ./data.Rmd                                   ⚠ 
##  ./distributed-r.Rmd                          ℹ 
##  ./excersises/01-introduction-walkthrough.Rmd ℹ 
##  ./extensions.Rmd                             ℹ 
##  ./index.Rmd                                  ✔ 
##  ./intro.Rmd                                  ℹ 
##  ./modeling.Rmd                               ℹ 
##  ./preface.Rmd                                ℹ 
##  ./references.Rmd                             ℹ 
##  ./slides/slides.Rmd                          ℹ 
##  ./starting.Rmd                               ℹ 
##  ./streaming.Rmd                              ℹ 
##  ./styler_feature.Rmd                         ✔ 
##  ./tuning.Rmd                                 ℹ 
## ────────────────────────────────────────────
## Status	Count	Legend 
## ✔ 	2	File unchanged.
## ℹ 	15	File changed.
## ✖ 	2	Styling threw an error.
## ────────────────────────────────────────────
## Please review the changes carefully!

style_book(filetype = c(".R", ".Rmd", ".Rnw"))
## Styling  25  files:
##  ./analysis.Rmd                               ✔ 
##  ./appendix.Rmd                               ✔ 
##  ./build.R                                    ℹ 
##  ./clusters.Rmd                               ✔ 
##  ./connections.Rmd                            ⚠ 
##  ./contributing.Rmd                           ✔ 
##  ./data.Rmd                                   ⚠ 
##  ./distributed-r.Rmd                          ✔ 
##  ./excersises/01-introduction-walkthrough.Rmd ✔ 
##  ./extensions.Rmd                             ✔ 
##  ./index.Rmd                                  ✔ 
##  ./intro.Rmd                                  ✔ 
##  ./modeling.Rmd                               ✔ 
##  ./preface.Rmd                                ✔ 
##  ./r/ascii.R                                  ✔ 
##  ./r/plots.R                                  ℹ 
##  ./r/render.R                                 ℹ 
##  ./r/utils.R                                  ℹ 
##  ./r/webshots.R                               ℹ 
##  ./references.Rmd                             ✔ 
##  ./slides/slides.Rmd                          ✔ 
##  ./starting.Rmd                               ✔ 
##  ./streaming.Rmd                              ✔ 
##  ./styler_feature.Rmd                         ✔ 
##  ./tuning.Rmd                                 ✔ 
## ────────────────────────────────────────────
## Status	Count	Legend 
## ✔ 	18	File unchanged.
## ℹ 	5	File changed.
## ✖ 	2	Styling threw an error.
## ────────────────────────────────────────────
## Please review the changes carefully!

[codecov-io]

Codecov Report

Merging #476 into master will decrease coverage by 0.59%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master     #476     +/-   ##
=========================================
- Coverage   89.77%   89.17%   -0.6%     
=========================================
  Files          36       36             
  Lines        1643     1654     +11     
=========================================
  Hits         1475     1475             
- Misses        168      179     +11

Impacted Files	Coverage Δ
R/ui.R	81.66% <0%> (-18.34%)	⬇️

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[lorenzwalthert]

Hi @jcrodriguez1989. Why not simply use style_dir(file_type = "rmd")? I don't think we should complicate the API with another function that has basically 100% overlap with existing functionality. Also, I don't see how this is bookdown specific. Can you elaborate on that? Or what am I missing?

[jcrodriguez1989]

Hi @lorenzwalthert. It is not bookdown specific, it is meant to be rmarkdown derivatives specific.
I found it useful to have this function available. It is as useful as using style_pkg, instead of simply using style_dir(file_type = "r") with some path exclusions.

It's just a suggestion 😄

[lorenzwalthert]

I understand that it would be nicer if you could call a function without specifying an argument for the file type. Unfortunately, the API decision was to not style .Rmd by default. This was probably a mistake. Maybe we will change this in a later release. Also, note that there are other issues such as #319 where we try to better understand configuring default values via yaml files. These would also apply to the Addins (not implemented in the solution mentioned in #319). You could install the experimental branch lorenzwalthert/styler@config (it is not guaranteed that we keep it up to date with r-lib/styler) and then change the default arguments in the config file. Feedback welcomed. But as I said, your proposed API change overlaps with existing functionality and is not bookdown specific so I hope you understand that I don't think we should merge this with master.

[jcrodriguez1989]

@lorenzwalthert I absolutely understand your determination.
It is good to see how much you are working on the package.
Thank you for contributing to the open source and R communities 🙂.

[lorenzwalthert]

Thanks. Also, if you have questions related to #319, you can ask me here, I'll try to help.