Merge pull request #3231 from jhlink/add-astyle-for-c-formatting

Add astyle for C/C++ formatting

autoload/ale/fix/registry.vim

@@ -160,6 +160,11 @@ let s:default_registry = {
 \       'suggested_filetypes': ['php'],
 \       'description': 'Fix PHP files with php-cs-fixer.',
 \   },
+\    'astyle': {
+\       'function': 'ale#fixers#astyle#Fix',
+\       'suggested_filetypes': ['c', 'cpp'],
+\       'description': 'Fix C/C++ with astyle.',
+\    },
 \   'clangtidy': {
 \       'function': 'ale#fixers#clangtidy#Fix',
 \       'suggested_filetypes': ['c', 'cpp', 'objc'],

autoload/ale/fixers/astyle.vim

@@ -0,0 +1,59 @@
+" Author: James Kim <jhlink@users.noreply.github.com>
+" Description: Fix C/C++ files with astyle.
+
+function! s:set_variables() abort
+    for l:ft in ['c', 'cpp']
+        call ale#Set(l:ft . '_astyle_executable', 'astyle')
+        call ale#Set(l:ft . '_astyle_project_options', '')
+    endfor
+endfunction
+
+call s:set_variables()
+
+
+function! ale#fixers#astyle#Var(buffer, name) abort
+    let l:ft = getbufvar(str2nr(a:buffer), '&filetype')
+    let l:ft = l:ft =~# 'cpp' ? 'cpp' : 'c'
+
+    return ale#Var(a:buffer, l:ft . '_astyle_' . a:name)
+endfunction
+
+" Try to find a project options file.
+function! ale#fixers#astyle#FindProjectOptions(buffer) abort
+    let l:proj_options = ale#fixers#astyle#Var(a:buffer, 'project_options')
+
+    " If user has set project options variable then use it and skip any searching.
+    " This would allow users to use project files named differently than .astylerc.
+    if !empty(l:proj_options)
+        return l:proj_options
+    endif
+
+    " Try to find nearest .astylerc file.
+    let l:proj_options = fnamemodify(ale#path#FindNearestFile(a:buffer, '.astylerc'), ':t')
+
+    if !empty(l:proj_options)
+        return l:proj_options
+    endif
+
+    " Try to find nearest _astylerc file.
+    let l:proj_options = fnamemodify(ale#path#FindNearestFile(a:buffer, '_astylerc'), ':t')
+
+    if !empty(l:proj_options)
+        return l:proj_options
+    endif
+
+    " If no project options file is found return an empty string.
+    return ''
+endfunction
+
+function! ale#fixers#astyle#Fix(buffer) abort
+    let l:executable = ale#fixers#astyle#Var(a:buffer, 'executable')
+    let l:proj_options = ale#fixers#astyle#FindProjectOptions(a:buffer)
+    let l:command = ' --stdin='
+
+    return {
+    \   'command': ale#Escape(l:executable)
+    \     . (empty(l:proj_options) ? '' : ' --project=' . l:proj_options)
+    \     . l:command
+    \}
+endfunction