diffit.vim

   1 " ============================================================================
   2 " File:        diffit.vim
   3 " Description: Show diff for current buffer
   4 " Maintainer:  Clemens Buchacher <drizzd@aon.at>
   5 " License:     GPLv2
   6 "
   7 " ============================================================================
   8 if exists('loaded_diffit')
   9     finish
  10 end
  11 let loaded_diffit = 1
  12
  13 let s:diffit_version = '0'
  14
  15 "for line continuation - i.e dont want C in &cpo
  16 let s:old_cpo = &cpo
  17 set cpo&vim
  18
  19 map <silent> <Leader>d :call <SID>Diffit()<CR>
  20
  21 function s:Error(msg)
  22         echohl ErrorMsg
  23         echon 'diffit: ' . a:msg
  24         echohl None
  25 endfunction
  26
  27 function s:Info(msg)
  28         echon 'diffit: ' . a:msg
  29 endfunction
  30
  31 function s:Die(msg)
  32         call s:Error('fatal: ' . a:msg)
  33         throw "diffit"
  34 endfunction
  35
  36 function s:System(...)
  37         let out = system(join(a:000))
  38         if v:shell_error
  39                 call s:Die(a:0 . ' failed: ' . out)
  40         end
  41         return out
  42 endfunction
  43
  44 function s:Header()
  45         let header = []
  46         for n in range(1, line('$'))
  47                         let l = getline(n)
  48                         if l =~ '^diff --git ' ||
  49                                                 \l =~ '^diff --cc ' ||
  50                                                 \l =~ '^diff --combined ' ||
  51                                                 \l =~ '^old mode ' ||
  52                                                 \l =~ '^new mode ' ||
  53                                                 \l =~ '^--- ' ||
  54                                                 \l =~ '^+++ '
  55                                 call add(header, l)
  56                                 continue
  57                         end
  58                         if l !~ '^index '
  59                                 break
  60                         end
  61         endfor
  62         return [header, n - 1]
  63 endfunction
  64
  65 function s:Exit()
  66         let view = b:view
  67         bdelete
  68         call winrestview(view)
  69 endfunction
  70
  71 function s:Diffit()
  72         if exists('b:diffit') && b:diffit == 1
  73                 call s:Exit()
  74                 return
  75         end
  76         try
  77                 call s:Diffit_init()
  78         catch /^diffit$/
  79                 if exists('b:diffit') && b:diffit == 1
  80                         call s:Exit()
  81                 end
  82         endtry
  83 endfunction
  84
  85 function s:Read_diff(pathlist)
  86         let diff = tempname()
  87         let path = ''
  88         for path in a:pathlist
  89                 let out = s:System('git diff', '--', path, '>', diff)
  90                 if getfsize(diff) > 0
  91                         break
  92                 end
  93         endfor
  94         return [diff, path]
  95 endfunction
  96
  97 function s:Write_diff(diff, orig)
  98         setlocal modifiable
  99         silent 1,$delete _
 100         silent exe 'read ' . a:diff
 101         silent 1delete _
 102         setlocal nomodifiable
 103
 104         if a:orig
 105                 let orig_pos = b:view['lnum']
 106                 let new_pos = s:Diffpos(orig_pos)
 107                 let view = copy(b:view)
 108                 let view['lnum'] = abs(new_pos)
 109                 if new_pos > 0
 110                         let view['topline'] += new_pos - orig_pos
 111                         let view['topline'] = max([1, view['topline']])
 112                 else
 113                         let view['topline'] = -new_pos - 4
 114                 end
 115                 let view['curswant'] += 1
 116                 let view['col'] += 1
 117                 call winrestview(view)
 118         else
 119                 call cursor(abs(s:Diffpos(0)), 1)
 120         end
 121 endfunction
 122
 123 function s:Diffit_init()
 124         update
 125         let out = s:System('git rev-parse',  '--is-inside-work-tree')
 126         if v:shell_error == 128 || split(out)[0] != 'true'
 127                 call s:Error('not inside work tree')
 128                 return
 129         elseif v:shell_error
 130                 call s:Error('git rev-parse failed: ' . out)
 131                 return
 132         end
 133         let out = s:System('git diff', '--name-only')
 134         let pathlist = split(out, '\n')
 135         if empty(pathlist)
 136                 call s:Info('no changes')
 137                 return
 138         end
 139         let orig_path = bufname('%')
 140         let k = index(pathlist, orig_path)
 141         if k > 0
 142                 call remove(pathlist, k)
 143                 call insert(pathlist, orig_path, 0)
 144         end
 145         let [diff, path] = s:Read_diff(pathlist)
 146         let orig = path == orig_path
 147         if getfsize(diff) == 0
 148                 call s:Info('no changes')
 149                 return
 150         end
 151
 152         let view = winsaveview()
 153         silent! exe 'edit ' . tempname()
 154         let b:pathlist = pathlist
 155         let b:view = view
 156         let b:diffit = 1
 157         setf git-diff
 158         if !exists('b:current_syntax')
 159                 setf diff
 160         end
 161         setlocal noswapfile
 162         setlocal buftype=nofile
 163         setlocal nowrap
 164         setlocal foldcolumn=0
 165         setlocal nobuflisted
 166
 167         iabc <buffer>
 168
 169         nnoremap <silent> <buffer> s :call <SID>Stage_hunk(line('.'))<CR>
 170         nnoremap <silent> <buffer> d :call <SID>Next_diff()<CR>
 171
 172         call s:Write_diff(diff, orig)
 173         echon '"' . path . '"'
 174 endfunction
 175
 176 function s:Next_diff()
 177         call remove(b:pathlist, 0)
 178         let [diff, path] = s:Read_diff(b:pathlist)
 179         if getfsize(diff) > 0
 180                 call s:Write_diff(diff, 0)
 181                 echon '"' . path . '"'
 182         else
 183                 call s:Exit()
 184         end
 185 endfunction
 186
 187 function s:Diffpos(orig_pos)
 188         let diffpos = -1
 189         let hunk_start = 1
 190         let hunk_end = 1
 191         call cursor(1, 1)
 192         while search('^@@', 'W') > 0
 193                 let [start, length] = matchlist(getline('.'),
 194                         \'^@@ -[0-9]*,[0-9]* +\%(\([0-9]*\),\)\?\([0-9]*\)')[1:2]
 195                 if empty(start)
 196                         let start = 1
 197                 end
 198                 if diffpos < 0
 199                         let diffpos = -line('.')
 200                 end
 201                 if start > a:orig_pos
 202                         break
 203                 end
 204                 let diffpos = line('.')
 205                 let hunk_start = start
 206                 let hunk_end = hunk_start + length - 1
 207         endwhile
 208         if diffpos < 0
 209                 return diffpos
 210         end
 211         let pos = hunk_start - 1
 212         let target_pos = min([a:orig_pos, hunk_end])
 213         while diffpos < line('$')
 214                 if getline(diffpos) =~ '^-'
 215                         let diffpos += 1
 216                         continue
 217                 end
 218                 if pos >= target_pos
 219                         break
 220                 end
 221                 let diffpos += 1
 222                 let pos += 1
 223         endwhile
 224
 225         if getline(diffpos) =~ '^-'
 226                 return -last
 227         else
 228                 return diffpos
 229         end
 230 endfunction
 231
 232 function s:Stage_hunk(pos)
 233         call cursor(a:pos, 1)
 234         let h_start = search('^@@', 'bcW')
 235         if h_start == 0
 236                 return
 237         end
 238         call cursor(h_start, 1)
 239         let h_end = search('^@@', 'nW')-1
 240         if h_end < 0
 241                 let h_end = line('$')
 242         end
 243         let h_range = h_start . ',' . h_end
 244
 245         let [patch, header_end] = s:Header()
 246         call extend(patch, getline(h_start, h_end))
 247         let patchfile = tempname()
 248         call writefile(patch, patchfile)
 249         let out = s:System('git apply', '--cached', '--whitespace=nowarn', patchfile)
 250
 251         setlocal modifiable
 252         silent exe h_range . 'delete _'
 253         setlocal nomodifiable
 254         if line('$') == header_end
 255                 call s:Next_diff()
 256                 return
 257         end
 258 endfunction
 259
 260 let &cpo = s:old_cpo