ale/ale_linters/python/flake8.vim

100 lines
3.4 KiB
VimL

" Author: w0rp <devw0rp@gmail.com>
" Description: flake8 for python files
let g:ale_python_flake8_executable =
\ get(g:, 'ale_python_flake8_executable', 'flake8')
" Support an old setting as a fallback.
let s:default_options = get(g:, 'ale_python_flake8_args', '')
let g:ale_python_flake8_options =
\ get(g:, 'ale_python_flake8_options', s:default_options)
let g:ale_python_flake8_use_global = get(g:, 'ale_python_flake8_use_global', 0)
" A map from Python executable paths to semver strings parsed for those
" executables, so we don't have to look up the version number constantly.
let s:version_cache = {}
function! ale_linters#python#flake8#GetExecutable(buffer) abort
if !ale#Var(a:buffer, 'python_flake8_use_global')
let l:virtualenv = ale#python#FindVirtualenv(a:buffer)
if !empty(l:virtualenv)
let l:ve_flake8 = l:virtualenv . '/bin/flake8'
if executable(l:ve_flake8)
return l:ve_flake8
endif
endif
endif
return ale#Var(a:buffer, 'python_flake8_executable')
endfunction
function! ale_linters#python#flake8#ClearVersionCache() abort
let s:version_cache = {}
endfunction
function! ale_linters#python#flake8#VersionCheck(buffer) abort
let l:executable = ale_linters#python#flake8#GetExecutable(a:buffer)
" If we have previously stored the version number in a cache, then
" don't look it up again.
if has_key(s:version_cache, l:executable)
" Returning an empty string skips this command.
return ''
endif
return fnameescape(ale_linters#python#flake8#GetExecutable(a:buffer))
\ . ' --version'
endfunction
" Get the flake8 version from the output, or the cache.
function! s:GetVersion(buffer, version_output) abort
let l:executable = ale_linters#python#flake8#GetExecutable(a:buffer)
let l:version = []
" Get the version from the cache.
if has_key(s:version_cache, l:executable)
return s:version_cache[l:executable]
endif
if !empty(a:version_output)
" Parse the version string, and store it in the cache.
let l:version = ale#semver#Parse(a:version_output[0])
let s:version_cache[l:executable] = l:version
endif
return l:version
endfunction
" flake8 versions 3 and up support the --stdin-display-name argument.
function! s:SupportsDisplayName(version) abort
return !empty(a:version) && ale#semver#GreaterOrEqual(a:version, [3, 0, 0])
endfunction
function! ale_linters#python#flake8#GetCommand(buffer, version_output) abort
let l:version = s:GetVersion(a:buffer, a:version_output)
" Only include the --stdin-display-name argument if we can parse the
" flake8 version, and it is recent enough to support it.
let l:display_name_args = s:SupportsDisplayName(l:version)
\ ? ' --stdin-display-name %s'
\ : ''
let l:options = ale#Var(a:buffer, 'python_flake8_options')
return fnameescape(ale_linters#python#flake8#GetExecutable(a:buffer))
\ . (!empty(l:options) ? ' ' . l:options : '')
\ . l:display_name_args . ' -'
endfunction
call ale#linter#Define('python', {
\ 'name': 'flake8',
\ 'executable_callback': 'ale_linters#python#flake8#GetExecutable',
\ 'command_chain': [
\ {'callback': 'ale_linters#python#flake8#VersionCheck'},
\ {'callback': 'ale_linters#python#flake8#GetCommand'},
\ ],
\ 'callback': 'ale#handlers#python#HandlePEP8Format',
\})