Add a fixer for r based on the styler package (#2401)

* Add styler as a new fixer for R files
* Add to the list of supported tools
* Add documentation

autoload/ale/fix/registry.vim

@@ -285,6 +285,11 @@ let s:default_registry = {
 \       'suggested_filetypes': ['kt'],
 \       'description': 'Fix Kotlin files with ktlint.',
 \   },
+\   'styler': {
+\       'function': 'ale#fixers#styler#Fix',
+\       'suggested_filetypes': ['r'],
+\       'description': 'Fix R files with styler.',
+\   },
 \   'latexindent': {
 \       'function': 'ale#fixers#latexindent#Fix',
 \       'suggested_filetypes': ['tex'],

autoload/ale/fixers/styler.vim

@@ -0,0 +1,16 @@
+" Author: tvatter <thibault.vatter@gmail.com>
+" Description: Fixing R files with styler.
+
+call ale#Set('r_styler_executable', 'Rscript')
+call ale#Set('r_styler_options', 'tidyverse_style')
+
+function! ale#fixers#styler#Fix(buffer) abort
+    return {
+    \   'command': 'Rscript --vanilla -e '
+    \       . '"suppressPackageStartupMessages(library(styler));'
+    \       . 'style_file(commandArgs(TRUE), style = '
+    \       . ale#Var(a:buffer, 'r_styler_options') . ')"'
+    \       . ' %t',
+    \   'read_temporary_file': 1,
+    \}
+endfunction