ale/ale_linters/swift/swiftlint.vim

" Author: David Mohundro <david@mohundro.com>, Gordon Fontenot <gordon@fonten.io>
" Description: swiftlint for swift files

call ale#Set('swift_swiftlint_executable', 'swiftlint')
call ale#Set('swift_swiftlint_use_global', get(g:, 'ale_use_global_executables', 0))

function! ale_linters#swift#swiftlint#GetExecutable(buffer) abort
    return ale#node#FindExecutable(a:buffer, 'swift_swiftlint', [
          \ 'Pods/SwiftLint/swiftlint',
          \ 'ios/Pods/SwiftLint/swiftlint',
          \ 'swiftlint',
          \])
endfunction

function! ale_linters#swift#swiftlint#GetCommand(buffer) abort
    let l:executable = ale_linters#swift#swiftlint#GetExecutable(a:buffer)
    let l:args = 'lint --use-stdin'

    return ale#Escape(l:executable)
          \ . ' ' .l:args
endfunction

function! ale_linters#swift#swiftlint#Handle(buffer, lines) abort
    let l:pattern = '\v^([a-zA-Z]?:?[^:]+):(\d+):(\d+)?:? ([^:]+): (.+)$'
    let l:output = []

    for l:match in ale#util#GetMatches(a:lines, l:pattern)
        let l:item = {
              \ 'lnum': str2nr(l:match[2]),
              \ 'type': l:match[4] is# 'error' ? 'E' : 'W',
              \ 'text': l:match[5],
              \}

        if l:match[4] is# 'error'
            let l:item.type = 'E'
        elseif l:match[4] is# 'note'
            let l:item.type = 'I'
        endif

        if !empty(l:match[3])
            let l:item.col = str2nr(l:match[3])
        endif

        " If the filename is something like <stdin>, <nofile> or -, then
        " this is an error for the file we checked.
        if l:match[1] isnot# '-' && l:match[1][0] isnot# '<'
            let l:item['filename'] = l:match[1]
        endif

        " Parse the code if it's there.
        let l:code_match = matchlist(l:item.text, '\v^(.+) \(([^ (]+)\)$')

        if !empty(l:code_match)
            let l:item.text = l:code_match[1]
            let l:item.code = l:code_match[2]
        endif

        call add(l:output, l:item)
    endfor

    return l:output
endfunction

call ale#linter#Define('swift', {
\   'name': 'swiftlint',
\   'executable_callback': 'ale_linters#swift#swiftlint#GetExecutable',
\   'command_callback': 'ale_linters#swift#swiftlint#GetCommand',
\   'callback': 'ale_linters#swift#swiftlint#Handle',
\})