fix: ruff not registered as fixer (#4393)

this commit fixes the issue reported at:
https://github.com/dense-analysis/ale/issues/4301#issuecomment-1359289391

it also had some code refactored and
tests added for ruff as fixer (missed in PR #4347).

3 files changed, 178 insertions, 16 deletions

diff --git a/autoload/ale/fix/registry.vim b/autoload/ale/fix/registry.vim
index b8d493f9..28e33926 100644
--- a/autoload/ale/fix/registry.vim
+++ b/autoload/ale/fix/registry.vim
@@ -580,6 +580,11 @@ let s:default_registry = {
 \       'function': 'ale#fixers#raco_fmt#Fix',
 \       'suggested_filetypes': ['racket'],
 \       'description': 'Fix Racket files with raco fmt.',
+\   },
+\   'ruff': {
+\       'function': 'ale#fixers#ruff#Fix',
+\       'suggested_filetypes': ['python'],
+\       'description': 'Fix python files with ruff.',
 \   }
 \}
 
diff --git a/autoload/ale/fixers/ruff.vim b/autoload/ale/fixers/ruff.vim
index 92f9b75b..56bcf3df 100644
--- a/autoload/ale/fixers/ruff.vim
+++ b/autoload/ale/fixers/ruff.vim
@@ -1,6 +1,13 @@
 " Author: Yining <zhang.yining@gmail.com>
 " Description: ruff as ALE fixer for python files
 
+call ale#Set('python_ruff_executable', 'ruff')
+call ale#Set('python_ruff_options', '')
+call ale#Set('python_ruff_use_global', get(g:, 'ale_use_global_executables', 0))
+call ale#Set('python_ruff_change_directory', 1)
+call ale#Set('python_ruff_auto_pipenv', 0)
+call ale#Set('python_ruff_auto_poetry', 0)
+
 function! ale#fixers#ruff#GetCwd(buffer) abort
     if ale#Var(a:buffer, 'python_ruff_change_directory')
         " Run from project root if found, else from buffer dir.
@@ -9,7 +16,7 @@ function! ale#fixers#ruff#GetCwd(buffer) abort
         return !empty(l:project_root) ? l:project_root : '%s:h'
     endif
 
-    return ''
+    return '%s:h'
 endfunction
 
 function! ale#fixers#ruff#GetExecutable(buffer) abort
@@ -26,29 +33,57 @@ function! ale#fixers#ruff#GetExecutable(buffer) abort
     return ale#python#FindExecutable(a:buffer, 'python_ruff', ['ruff'])
 endfunction
 
-function! ale#fixers#ruff#GetCommand(buffer, version) abort
-    let l:executable = ale_linters#python#ruff#GetExecutable(a:buffer)
+function! ale#fixers#ruff#GetCommand(buffer) abort
+    let l:executable = ale#fixers#ruff#GetExecutable(a:buffer)
     let l:exec_args = l:executable =~? 'pipenv\|poetry$'
     \   ? ' run ruff'
     \   : ''
 
-    " NOTE: ruff version `0.0.72` implement `--fix` with stdin
     return ale#Escape(l:executable) . l:exec_args
-    \   . ale#Pad(ale#Var(a:buffer, 'python_ruff_options'))
-    \   . ' --fix'
-    \   .  (ale#semver#GTE(a:version, [0, 0, 72]) ? ' -' : ' %s')
 endfunction
 
-function! ale#fixers#ruff#Fix(buffer) abort
-    let l:fix_cmd = {buffer -> ale#semver#RunWithVersionCheck(
-    \     buffer,
-    \     ale#fixers#ruff#GetExecutable(buffer),
-    \     '%e --version',
-    \     function('ale#fixers#ruff#GetCommand'),
-    \ )}(a:buffer)
+function! ale#fixers#ruff#FixForVersion(buffer, version) abort
+    let l:executable = ale#fixers#ruff#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_options')
+
+    if !empty(l:options)
+        call add(l:cmd, l:options)
+    endif
+
+    " 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, '--stdin-filename '.ale#Escape(ale#path#Simplify(l:fname)))
+
+    call add(l:cmd, '--fix')
+
+    " NOTE: ruff version `0.0.72` implements `--fix` with stdin
+    if ale#semver#GTE(a:version, [0, 0, 72])
+        call add(l:cmd, '-')
+    else
+        call add(l:cmd, '%s')
+    endif
 
     return {
-    \ 'cwd': ale#fixers#ruff#GetCwd(a:buffer),
-    \ 'command': l:fix_cmd,
+    \   'cwd': ale#fixers#ruff#GetCwd(a:buffer),
+    \   'command': join(l:cmd, ' '),
     \}
 endfunction
+
+function! ale#fixers#ruff#Fix(buffer) abort
+    let l:executable = ale#fixers#ruff#GetExecutable(a:buffer)
+    let l:command = ale#fixers#ruff#GetCommand(a:buffer) . ale#Pad('--version')
+
+    return ale#semver#RunWithVersionCheck(
+    \     a:buffer,
+    \     l:executable,
+    \     l:command,
+    \     function('ale#fixers#ruff#FixForVersion'),
+    \)
+endfunction
diff --git a/test/fixers/test_ruff_fixer_callback.vader b/test/fixers/test_ruff_fixer_callback.vader
new file mode 100644
index 00000000..68c7a942
--- /dev/null
+++ b/test/fixers/test_ruff_fixer_callback.vader
@@ -0,0 +1,122 @@
+Before:
+  call ale#assert#SetUpFixerTest('python', 'ruff')
+
+  let b:bin_dir = has('win32') ? 'Scripts' : 'bin'
+
+After:
+  call ale#assert#TearDownFixerTest()
+
+  unlet! g:dir
+  unlet! b:bin_dir
+
+Execute(The ruff callback should return the correct default values):
+  let file_path = g:dir . '/../test-files/python/with_virtualenv/subdir/foo/bar.py'
+
+  silent execute 'file ' . fnameescape(file_path)
+
+  let fname = ale#Escape(ale#path#Simplify(file_path))
+
+  " --fix does not support stdin until 0.0.72
+  GivenCommandOutput ['ruff 0.0.72']
+  AssertFixer
+  \ {
+  \   'cwd': ale#path#Simplify(g:dir . '/../test-files/python/with_virtualenv/subdir'),
+  \   'command': ale#Escape(ale#path#Simplify(g:dir . '/../test-files/python/with_virtualenv/env/' . b:bin_dir . '/ruff')) . ' --stdin-filename ' . fname  . ' --fix -',
+  \ }
+
+Execute(The ruff callback should not use stdin for older versions (< 0.0.72)):
+  let file_path = g:dir . '/../test-files/python/with_virtualenv/subdir/foo/bar.py'
+
+  silent execute 'file ' . fnameescape(file_path)
+
+  let fname = ale#Escape(ale#path#Simplify(file_path))
+
+  " --fix does not support stdin until 0.0.72
+  GivenCommandOutput ['ruff 0.0.71']
+  AssertFixer
+  \ {
+  \   'cwd': ale#path#Simplify(g:dir . '/../test-files/python/with_virtualenv/subdir'),
+  \   'command': ale#Escape(ale#path#Simplify(g:dir . '/../test-files/python/with_virtualenv/env/' . b:bin_dir . '/ruff')) . ' --stdin-filename ' . fname . ' --fix %s',
+  \ }
+
+Execute(The ruff callback should not change directory if the option is set to 0):
+  let g:ale_python_ruff_change_directory = 0
+
+  let file_path = g:dir . '/../test-files/python/with_virtualenv/subdir/foo/bar.py'
+
+  silent execute 'file ' . fnameescape(file_path)
+
+  let fname = ale#Escape(ale#path#Simplify(file_path))
+
+  " --fix does not support stdin until 0.0.72
+  GivenCommandOutput ['ruff 0.0.72']
+  AssertFixer
+  \ {
+  \   'cwd': '%s:h',
+  \   'command': ale#Escape(ale#path#Simplify(g:dir . '/../test-files/python/with_virtualenv/env/' . b:bin_dir . '/ruff')) . ' --stdin-filename ' . fname . ' --fix -',
+  \ }
+
+Execute(The ruff callback should respect custom options):
+  let g:ale_python_ruff_options = '--ignore F401 -q'
+
+  let file_path = g:dir . '/../test-files/python/with_virtualenv/subdir/foo/bar.py'
+
+  silent execute 'file ' . fnameescape(file_path)
+
+  let fname = ale#Escape(ale#path#Simplify(file_path))
+
+  GivenCommandOutput ['ruff 0.0.72']
+  AssertFixer
+  \ {
+  \   'cwd': ale#path#Simplify(g:dir . '/../test-files/python/with_virtualenv/subdir'),
+  \   'command': ale#Escape(ale#path#Simplify(g:dir . '/../test-files/python/with_virtualenv/env/' . b:bin_dir . '/ruff'))
+  \     . ' --ignore F401 -q --stdin-filename '. fname . ' --fix -',
+  \ }
+
+Execute(Pipenv is detected when python_ruff_auto_pipenv is set):
+  let g:ale_python_ruff_auto_pipenv = 1
+  let g:ale_python_ruff_change_directory = 0
+
+  let file_path = '../test-files/python/pipenv/whatever.py'
+
+  call ale#test#SetFilename(file_path)
+
+  let fname = ale#Escape(ale#path#Simplify(g:dir . '/'. file_path))
+
+  GivenCommandOutput ['ruff 0.0.72']
+  AssertFixer
+  \ {
+  \   'cwd': '%s:h',
+  \   'command': ale#Escape('pipenv') . ' run ruff --stdin-filename ' . fname . ' --fix -'
+  \ }
+
+Execute(Poetry is detected when python_ruff_auto_poetry is set):
+  let g:ale_python_ruff_auto_poetry = 1
+  let g:ale_python_ruff_change_directory = 0
+
+  call ale#test#SetFilename('../test-files/python/poetry/whatever.py')
+
+  let fname = ale#Escape(ale#path#Simplify(g:dir .'/../test-files/python/poetry/whatever.py'))
+
+  GivenCommandOutput ['ruff 0.0.72']
+  AssertFixer
+  \ {
+  \   'cwd': '%s:h',
+  \   'command': ale#Escape('poetry') . ' run ruff --stdin-filename ' . fname . ' --fix -'
+  \ }
+
+Execute(Poetry is detected when python_ruff_auto_poetry is set, and cwd respects change_directory option):
+  let g:ale_python_ruff_auto_poetry = 1
+  let g:ale_python_ruff_change_directory = 1
+
+  call ale#test#SetFilename('../test-files/python/poetry/whatever.py')
+
+  let fname = ale#Escape(ale#path#Simplify(g:dir .'/../test-files/python/poetry/whatever.py'))
+
+  GivenCommandOutput ['ruff 0.0.72']
+  AssertFixer
+  \ {
+  \   'cwd': ale#path#Simplify(g:dir . '/../test-files/python/poetry'),
+  \   'command': ale#Escape('poetry') . ' run ruff --stdin-filename ' . fname . ' --fix -'
+  \ }
+