Improve pylama linter output handling (#4106)

* Use JSON format for newer pylama version

https://github.com/klen/pylama/blob/develop/Changelog

The --format json option is added in pylama version 8.1.4.

* Fix linting warnings for pylama

1 files changed, 70 insertions, 15 deletions

diff --git a/ale_linters/python/pylama.vim b/ale_linters/python/pylama.vim
index 73b59b07..14f8071a 100644
--- a/ale_linters/python/pylama.vim
+++ b/ale_linters/python/pylama.vim
@@ -22,6 +22,22 @@ function! ale_linters#python#pylama#GetExecutable(buffer) abort
     return ale#python#FindExecutable(a:buffer, 'python_pylama', ['pylama'])
 endfunction
 
+function! ale_linters#python#pylama#RunWithVersionCheck(buffer) abort
+    let l:executable = ale_linters#python#pylama#GetExecutable(a:buffer)
+    let l:exec_args = l:executable =~? 'pipenv\|poetry$'
+    \   ? ' run pylama'
+    \   : ''
+
+    let l:command = ale#Escape(l:executable) . l:exec_args . ' --version'
+
+    return ale#semver#RunWithVersionCheck(
+    \   a:buffer,
+    \   l:executable,
+    \   l:command,
+    \   function('ale_linters#python#pylama#GetCommand'),
+    \)
+endfunction
+
 function! ale_linters#python#pylama#GetCwd(buffer) abort
     if ale#Var(a:buffer, 'python_pylama_change_directory')
         " Pylama loads its configuration from the current directory only, and
@@ -35,27 +51,33 @@ function! ale_linters#python#pylama#GetCwd(buffer) abort
     return ''
 endfunction
 
-function! ale_linters#python#pylama#GetCommand(buffer) abort
+function! ale_linters#python#pylama#GetCommand(buffer, version) abort
     let l:executable = ale_linters#python#pylama#GetExecutable(a:buffer)
     let l:exec_args = l:executable =~? 'pipenv\|poetry$'
     \   ? ' run pylama'
     \   : ''
 
+    " json format is added in version 8.1.4
+    " https://github.com/klen/pylama/blob/develop/Changelog
+    let l:format_json_args = ale#semver#GTE(a:version, [8, 1, 4])
+    \   ? ' --format json'
+    \   : ''
+
     " Note: Using %t to lint changes would be preferable, but many pylama
     " checks use surrounding paths (e.g. C0103 module name, E0402 relative
     " import beyond top, etc.).  Neither is ideal.
     return ale#Escape(l:executable) . l:exec_args
     \   . ale#Pad(ale#Var(a:buffer, 'python_pylama_options'))
+    \   . l:format_json_args
     \   . ' %s'
 endfunction
 
-function! ale_linters#python#pylama#Handle(buffer, lines) abort
+function! ale_linters#python#pylama#Handle(buffer, version, lines) abort
     if empty(a:lines)
         return []
     endif
 
     let l:output = ale#python#HandleTraceback(a:lines, 1)
-    let l:pattern = '\v^.{-}:([0-9]+):([0-9]+): +%(([A-Z][0-9]+):? +)?(.*)$'
 
     " First letter of error code is a pylint-compatible message type
     " http://pylint.pycqa.org/en/latest/user_guide/output.html#source-code-analysis-section
@@ -75,16 +97,41 @@ function! ale_linters#python#pylama#Handle(buffer, lines) abort
     \   'D': 'style',
     \}
 
-    for l:match in ale#util#GetMatches(a:lines, l:pattern)
-        call add(l:output, {
-        \   'lnum': str2nr(l:match[1]),
-        \   'col': str2nr(l:match[2]),
-        \   'code': l:match[3],
-        \   'type': get(l:pylint_type_to_ale_type, l:match[3][0], 'W'),
-        \   'sub_type': get(l:pylint_type_to_ale_sub_type, l:match[3][0], ''),
-        \   'text': l:match[4],
-        \})
-    endfor
+    if ale#semver#GTE(a:version, [8, 1, 4])
+        try
+            let l:errors = json_decode(join(a:lines, ''))
+        catch
+            return l:output
+        endtry
+
+        if empty(l:errors)
+            return l:output
+        endif
+
+        for l:error in l:errors
+            call add(l:output, {
+            \   'lnum': l:error['lnum'],
+            \   'col': l:error['col'],
+            \   'code': l:error['number'],
+            \   'type': get(l:pylint_type_to_ale_type, l:error['etype'], 'W'),
+            \   'sub_type': get(l:pylint_type_to_ale_sub_type, l:error['etype'], ''),
+            \   'text': printf('%s [%s]', l:error['message'], l:error['source']),
+            \})
+        endfor
+    else
+        let l:pattern = '\v^.{-}:([0-9]+):([0-9]+): +%(([A-Z][0-9]+):? +)?(.*)$'
+
+        for l:match in ale#util#GetMatches(a:lines, l:pattern)
+            call add(l:output, {
+            \   'lnum': str2nr(l:match[1]),
+            \   'col': str2nr(l:match[2]),
+            \   'code': l:match[3],
+            \   'type': get(l:pylint_type_to_ale_type, l:match[3][0], 'W'),
+            \   'sub_type': get(l:pylint_type_to_ale_sub_type, l:match[3][0], ''),
+            \   'text': l:match[4],
+            \})
+        endfor
+    endif
 
     return l:output
 endfunction
@@ -93,7 +140,15 @@ call ale#linter#Define('python', {
 \   'name': 'pylama',
 \   'executable': function('ale_linters#python#pylama#GetExecutable'),
 \   'cwd': function('ale_linters#python#pylama#GetCwd'),
-\   'command': function('ale_linters#python#pylama#GetCommand'),
-\   'callback': 'ale_linters#python#pylama#Handle',
+\   'command': function('ale_linters#python#pylama#RunWithVersionCheck'),
+\   'callback': {buffer, lines -> ale#semver#RunWithVersionCheck(
+\       buffer,
+\       ale_linters#python#pylama#GetExecutable(buffer),
+\       '%e --version',
+\       {buffer, version -> ale_linters#python#pylama#Handle(
+\           buffer,
+\           l:version,
+\           lines)},
+\   )},
 \   'lint_file': 1,
 \})