Close #2522 - Check pylint on the fly

Newer versions of pylint will now check your code as you type. Older
versions will still only check the file on disk.

Co-authored-by: Oliver Wiegers <oliver.wiegers@gmail.com>

1 files changed, 30 insertions, 8 deletions

diff --git a/ale_linters/python/pylint.vim b/ale_linters/python/pylint.vim
index b16d5355..44eea246 100644
--- a/ale_linters/python/pylint.vim
+++ b/ale_linters/python/pylint.vim
@@ -17,7 +17,7 @@ function! ale_linters#python#pylint#GetExecutable(buffer) abort
     return ale#python#FindExecutable(a:buffer, 'python_pylint', ['pylint'])
 endfunction
 
-function! ale_linters#python#pylint#GetCommand(buffer) abort
+function! ale_linters#python#pylint#GetCommand(buffer, version) abort
     let l:cd_string = ''
 
     if ale#Var(a:buffer, 'python_pylint_change_directory')
@@ -38,17 +38,23 @@ function! ale_linters#python#pylint#GetCommand(buffer) abort
 
     return l:cd_string
     \   . ale#Escape(l:executable) . l:exec_args
-    \   . ' ' . ale#Var(a:buffer, 'python_pylint_options')
+    \   . ale#Pad(ale#Var(a:buffer, 'python_pylint_options'))
     \   . ' --output-format text --msg-template="{path}:{line}:{column}: {msg_id} ({symbol}) {msg}" --reports n'
+    \   .  (ale#semver#GTE(a:version, [2, 4, 0]) ? ' --from-stdin' : '')
     \   . ' %s'
 endfunction
 
 function! ale_linters#python#pylint#Handle(buffer, lines) abort
+    let l:output = ale#python#HandleTraceback(a:lines, 10)
+
+    if !empty(l:output)
+        return l:output
+    endif
+
     " Matches patterns like the following:
     "
     " test.py:4:4: W0101 (unreachable) Unreachable code
     let l:pattern = '\v^[a-zA-Z]?:?[^:]+:(\d+):(\d+): ([[:alnum:]]+) \(([^(]*)\) (.*)$'
-    let l:output = []
 
     for l:match in ale#util#GetMatches(a:lines, l:pattern)
         "let l:failed = append(0, l:match)
@@ -71,13 +77,19 @@ function! ale_linters#python#pylint#Handle(buffer, lines) abort
             let l:code_out = l:match[4]
         endif
 
-        call add(l:output, {
+        let l:item = {
         \   'lnum': l:match[1] + 0,
         \   'col': l:match[2] + 1,
         \   'text': l:match[5],
         \   'code': l:code_out,
-        \   'type': l:code[:0] is# 'E' ? 'E' : 'W',
-        \})
+        \   'type': 'W',
+        \}
+
+        if l:code[:0] is# 'E'
+            let l:item.type = 'E'
+        endif
+
+        call add(l:output, l:item)
     endfor
 
     return l:output
@@ -86,7 +98,17 @@ endfunction
 call ale#linter#Define('python', {
 \   'name': 'pylint',
 \   'executable': function('ale_linters#python#pylint#GetExecutable'),
-\   'command': function('ale_linters#python#pylint#GetCommand'),
+\   'lint_file': {buffer -> ale#semver#RunWithVersionCheck(
+\       buffer,
+\       ale#Var(buffer, 'python_pylint_executable'),
+\       '%e --version',
+\       {buffer, version -> !ale#semver#GTE(version, [2, 4, 0])},
+\   )},
+\   'command': {buffer -> ale#semver#RunWithVersionCheck(
+\       buffer,
+\       ale#Var(buffer, 'python_pylint_executable'),
+\       '%e --version',
+\       function('ale_linters#python#pylint#GetCommand'),
+\   )},
 \   'callback': 'ale_linters#python#pylint#Handle',
-\   'lint_file': 1,
 \})