" Heuristically set buffer options
"
" Modified version of vim-sleuth:
" - softtab and tabstop reduced from 8 to 2
" - number of considered lines reduced from 1024 to 64
" - maximum 6 other files are checked instead of 20
" - check maximum of files 2 per directory level instead of 8
" - maximum of 3 directory levels are checked
" - globs are concatenated for performance
if exists("g:loaded_sleuth") || v:version < 700 || &cp
finish
endif
let g:loaded_sleuth = 1
function! s:guess(lines) abort
let options = {}
let heuristics = {'spaces': 0, 'hard': 0, 'soft': 0}
let ccomment = 0
let podcomment = 0
let triplequote = 0
let backtick = 0
let xmlcomment = 0
let softtab = repeat(' ', 2)
for line in a:lines
if !len(line) || line =~# '^\s*$'
continue
endif
if line =~# '^\s*/\*'
let ccomment = 1
endif
if ccomment
if line =~# '\*/'
let ccomment = 0
endif
continue
endif
if line =~# '^=\w'
let podcomment = 1
endif
if podcomment
if line =~# '^=\%(end\|cut\)\>'
let podcomment = 0
endif
continue
endif
if triplequote
if line =~# '^[^"]*"""[^"]*$'
let triplequote = 0
endif
continue
elseif line =~# '^[^"]*"""[^"]*$'
let triplequote = 1
endif
if backtick
if line =~# '^[^`]*`[^`]*$'
let backtick = 0
endif
continue
elseif &filetype ==# 'go' && line =~# '^[^`]*`[^`]*$'
let backtick = 1
endif
if line =~# '^\s*<\!--'
let xmlcomment = 1
endif
if xmlcomment
if line =~# '-->'
let xmlcomment = 0
endif
continue
endif
if line =~# '^\t'
let heuristics.hard += 1
elseif line =~# '^' . softtab
let heuristics.soft += 1
endif
if line =~# '^ '
let heuristics.spaces += 1
endif
let indent = len(matchstr(substitute(line, '\t', softtab, 'g'), '^ *'))
if indent > 1 && (indent < 4 || indent % 2 == 0) &&
\ get(options, 'shiftwidth', 99) > indent
let options.shiftwidth = indent
endif
endfor
if heuristics.hard && !heuristics.spaces
return {'expandtab': 0, 'shiftwidth': &tabstop}
elseif heuristics.soft != heuristics.hard
let options.expandtab = heuristics.soft > heuristics.hard
if heuristics.hard
let options.tabstop = 2
endif
endif
return options
endfunction
function! s:apply_if_ready(options) abort
if !has_key(a:options, 'expandtab') || !has_key(a:options, 'shiftwidth')
return 0
else
for [option, value] in items(a:options)
call setbufvar('', '&'.option, value)
endfor
return 1
endif
endfunction
function! s:detect() abort
if &buftype ==# 'help'
return
endif
let options = s:guess(getline(1, 64))
if s:apply_if_ready(options)
return
endif
let c = 6
let pattern = c > 0 ? sleuth#GlobForFiletype(&filetype) : ''
let dir = expand('%:p:h')
let level = 3
while isdirectory(dir) && dir !=# fnamemodify(dir, ':h') && c > 0 && level > 0
let level -= 1
for neighbor in glob(dir.'/'.pattern,0,1)[0:1]
if neighbor !=# expand('%:p') && filereadable(neighbor)
call extend(options, s:guess(readfile(neighbor, '', 32)), 'keep')
let c -= 1
endif
if s:apply_if_ready(options)
let b:sleuth_culprit = neighbor
return
endif
if c <= 0
break
endif
endfor
if c <= 0
break
endif
let dir = fnamemodify(dir, ':h')
endwhile
if has_key(options, 'shiftwidth')
return s:apply_if_ready(extend({'expandtab': 1}, options))
endif
endfunction
setglobal smarttab
if !exists('g:did_indent_on')
filetype indent on
endif
augroup polyglot
autocmd!
autocmd FileType * call s:detect()
augroup END
