[Python-Dev] PEP 7 updated

[Trent Nelson]

> Does anyone know of a way to teach vim that C sources in a python checkout should have 4-space indents without changing the defaults for other C files?

I use this in my vimrc:

"----------------------------------------------------------------------------"
" indentation: use detectindent plugin if possible
"----------------------------------------------------------------------------"
set autoindent
set smartindent
try
     let g:detectindent_preferred_expandtab = 1
     let g:detectindent_preferred_tabsize = 8
     let g:detectindent_preferred_indent = 4

     source $VIMRUNTIME/plugin/detectindent.vim
     au BufNewFile,BufRead * .* DetectIndent
catch
     set smarttab
     set expandtab
     set tabstop=8
     set shiftwidth=4
     set softtabstop=4
     set textwidth=80
endtry

*** And this is plugin/detectindent.vim:

" Name:          detectindent (global plugin)
" Version:       1.0
" Author:        Ciaran McCreesh <ciaranm at gentoo.org>
" Updates:       http://dev.gentoo.org/~ciaranm/vim/
" Purpose:       Detect file indent settings
"
" License:       You may redistribute this plugin under the same terms 
as Vim
"                itself.
"
" Usage:         :DetectIndent
"
"                " to prefer expandtab to noexpandtab when detection is
"                " impossible:
"                :let g:detectindent_preferred_expandtab = 1
"
"                " to set a preferred indent level when detection is
"                " impossible:
"                :let g:detectindent_preferred_indent = 4
"
" Requirements:  Untested on Vim versions below 6.2

fun! <SID>IsCommentStart(line)
     " &comments isn't reliable
     if &ft == "c" || &ft == "cpp"
         return -1 != match(a:line, '/\*')
     else
         return 0
     endif
endfun

fun! <SID>IsCommentEnd(line)
     if &ft == "c" || &ft == "cpp"
         return -1 != match(a:line, '\*/')
     else
         return 0
     endif
endfun

fun! <SID>DetectIndent()
     let l:has_leading_tabs            = 0
     let l:has_leading_spaces          = 0
     let l:shortest_leading_spaces_run = 0
     let l:longest_leading_spaces_run  = 0

     let l:idx_end = line("$")
     let l:idx = 1
     while l:idx <= l:idx_end
         let l:line = getline(l:idx)

         " try to skip over comment blocks, they can give really screwy 
indent
         " settings in c/c++ files especially
         if <SID>IsCommentStart(l:line)
             while l:idx <= l:idx_end && ! <SID>IsCommentEnd(l:line)
                 let l:line = getline(l:idx)
                 let l:idx = l:idx + 1
             endwhile
             let l:idx = l:idx + 1
             continue
         endif

         let l:leading_char = strpart(l:line, 0, 1)

         if l:leading_char == "\t"
             let l:has_leading_tabs = 1

         elseif l:leading_char == " "
             " only interested if we don't have a run of spaces followed 
by a
             " tab.
             if -1 == match(l:line, '^ \+\t')
                 let l:has_leading_spaces = 1
                 let l:spaces = strlen(matchstr(l:line, '^ \+'))
                 if l:shortest_leading_spaces_run == 0 ||
                             \ l:spaces < l:shortest_leading_spaces_run
                     let l:shortest_leading_spaces_run = l:spaces
                 endif
                 if l:spaces > l:longest_leading_spaces_run
                     let l:longest_leading_spaces_run = l:spaces
                 endif
             endif

         endif

         let l:idx = l:idx + 1
     endwhile

     if l:has_leading_tabs && ! l:has_leading_spaces
         " tabs only, no spaces
         set noexpandtab
         if exists("g:detectindent_preferred_tabsize")
             let &shiftwidth  = g:detectindent_preferred_indent
             let &tabstop     = g:detectindent_preferred_indent
         endif

     elseif l:has_leading_spaces && ! l:has_leading_tabs
         " spaces only, no tabs
         set expandtab
         let &shiftwidth  = l:shortest_leading_spaces_run

     elseif l:has_leading_spaces && l:has_leading_tabs
         " spaces and tabs
         set noexpandtab
         let &shiftwidth = l:shortest_leading_spaces_run

         " mmmm, time to guess how big tabs are
         if l:longest_leading_spaces_run < 2
             let &tabstop = 2
         elseif l:longest_leading_spaces_run < 4
             let &tabstop = 4
         else
             let &tabstop = 8
         endif

     else
         " no spaces, no tabs
         if exists("g:detectindent_preferred_tabsize")
             let &shiftwidth  = g:detectindent_preferred_indent
             let &tabstop     = g:detectindent_preferred_indent
         endif
         if exists("g:detectindent_preferred_expandtab")
             set expandtab
         endif

     endif
endfun

command! -nargs=0 DetectIndent call <SID>DetectIndent()