Adding support for ruff formatter (#4645)

autoload/ale/fix/registry.vim

@@ -611,6 +611,11 @@ let s:default_registry = {
 \       'suggested_filetypes': ['python'],
 \       'description': 'Fix python files with ruff.',
 \   },
+\   'ruff_format': {
+\       'function': 'ale#fixers#ruff_format#Fix',
+\       'suggested_filetypes': ['python'],
+\       'description': 'Fix python files with the ruff formatter.',
+\   },
 \   'pycln': {
 \       'function': 'ale#fixers#pycln#Fix',
 \       'suggested_filetypes': ['python'],

autoload/ale/fixers/ruff_format.vim

@@ -0,0 +1,72 @@
+" Author: Yining <zhang.yining@gmail.com>, Joseph Henrich <crimsonknave@gmail.com>
+" Description: ruff formatter as ALE fixer for python files
+
+call ale#Set('python_ruff_format_executable', 'ruff')
+call ale#Set('python_ruff_format_options', '')
+call ale#Set('python_ruff_format_use_global', get(g:, 'ale_use_global_executables', 0))
+call ale#Set('python_ruff_format_change_directory', 1)
+call ale#Set('python_ruff_format_auto_pipenv', 0)
+call ale#Set('python_ruff_format_auto_poetry', 0)
+
+function! ale#fixers#ruff_format#GetCwd(buffer) abort
+    if ale#Var(a:buffer, 'python_ruff_format_change_directory')
+        " Run from project root if found, else from buffer dir.
+        let l:project_root = ale#python#FindProjectRoot(a:buffer)
+
+        return !empty(l:project_root) ? l:project_root : '%s:h'
+    endif
+
+    return '%s:h'
+endfunction
+
+function! ale#fixers#ruff_format#GetExecutable(buffer) abort
+    if (ale#Var(a:buffer, 'python_auto_pipenv') || ale#Var(a:buffer, 'python_ruff_format_auto_pipenv'))
+    \ && ale#python#PipenvPresent(a:buffer)
+        return 'pipenv'
+    endif
+
+    if (ale#Var(a:buffer, 'python_auto_poetry') || ale#Var(a:buffer, 'python_ruff_format_auto_poetry'))
+    \ && ale#python#PoetryPresent(a:buffer)
+        return 'poetry'
+    endif
+
+    return ale#python#FindExecutable(a:buffer, 'python_ruff_format', ['ruff'])
+endfunction
+
+function! ale#fixers#ruff_format#GetCommand(buffer) abort
+    let l:executable = ale#fixers#ruff_format#GetExecutable(a:buffer)
+    let l:exec_args = l:executable =~? 'pipenv\|poetry$'
+    \   ? ' run ruff'
+    \   : ''
+
+    return ale#Escape(l:executable) . l:exec_args
+endfunction
+
+function! ale#fixers#ruff_format#Fix(buffer) abort
+    let l:executable = ale#fixers#ruff_format#GetExecutable(a:buffer)
+    let l:cmd = [ale#Escape(l:executable)]
+
+    if l:executable =~? 'pipenv\|poetry$'
+        call extend(l:cmd, ['run', 'ruff'])
+    endif
+
+    let l:options = ale#Var(a:buffer, 'python_ruff_format_options')
+
+    " when --stdin-filename present, ruff will use it for proj root resolution
+    " https://github.com/charliermarsh/ruff/pull/1281
+    let l:fname = expand('#' . a:buffer . '...')
+    call add(l:cmd, 'format')
+
+    if !empty(l:options)
+        call add(l:cmd, l:options)
+    endif
+
+    call add(l:cmd, '--stdin-filename '.ale#Escape(ale#path#Simplify(l:fname)))
+
+    call add(l:cmd, '-')
+
+    return {
+    \   'cwd': ale#fixers#ruff_format#GetCwd(a:buffer),
+    \   'command': join(l:cmd, ' '),
+    \}
+endfunction