Handle .git in file system root

References https://github.com/tpope/vim-fugitive/issues/908

README.markdown

@@ -35,9 +35,15 @@ and you never get any warnings about the file changing outside Vim.
 making it like `git add` when called from a work tree file and like
 `git checkout` when called from the index or a blob in history.
 
-Use `:Gbrowse` to open the current file on GitHub, with optional line
-range (try it in visual mode!).  If your current repository isn't on
-GitHub, `git instaweb` will be spun up instead.
+Use `:Gbrowse` to open the current file on the web front-end of your favorite
+hosting provider, with optional line range (try it in visual mode!).  Built-in
+support is provided for `git instaweb`, and plugins are available for popular
+providers such as [GitHub][rhubarb.vim], [GitLab][fugitive-gitlab.vim], and
+[Bitbucket][fubitive.vim].
+
+[rhubarb.vim]: https://github.com/tpope/vim-rhubarb
+[fugitive-gitlab.vim]: https://github.com/shumphrey/fugitive-gitlab.vim
+[fubitive.vim]: https://github.com/tommcdo/vim-fubitive
 
 Add `%{fugitive#statusline()}` to `'statusline'` to get an indicator
 with the current branch in (surprise!) your statusline.

doc/fugitive.txt

@@ -57,6 +57,10 @@ that are part of Git repositories).
                         q     close status
                         r     reload status
                         S     |:Gvsplit|
+                        U     |:Git| checkout
+                        U     |:Git| checkout HEAD (staged files)
+                        U     |:Git| clean (untracked files)
+                        U     |:Git| rm (unmerged files)
 
                                                 *fugitive-:Gcommit*
 :Gcommit [args]         A wrapper around git-commit.  If there is nothing
@@ -91,10 +95,10 @@ that are part of Git repositories).
 :Gfetch [args]          Like |:Gpush|, but for git-fetch.
 
                                                 *fugitive-:Ggrep*
-:Ggrep [args]           |:grep| with git-grep as 'grepprg'.
+:Ggrep[!] [args]        |:grep|[!] with git-grep as 'grepprg'.
 
                                                 *fugitive-:Glgrep*
-:Glgrep [args]          |:lgrep| with git-grep as 'grepprg'.
+:Glgrep[!] [args]       |:lgrep|[!] with git-grep as 'grepprg'.
 
                                                 *fugitive-:Glog*
 :Glog [args]            Load all previous revisions of the current file into
@@ -177,7 +181,9 @@ that are part of Git repositories).
                         to the right or bottom, depending on 'diffopt' and
                         the width of the window relative to 'textwidth'.  Use
                         |do| and |dp| and write to the index file to simulate
-                        "git add --patch".
+                        "git add --patch". For the three-way diff, there is
+                        also d2o and d3o pulling the hunk to the middle from
+                        the left or the right window, respectively.
 
                                                 *fugitive-:Gsdiff*
 :Gsdiff [revision]      Like |:Gdiff|, but always split horizontally.
@@ -228,9 +234,7 @@ that are part of Git repositories).
                         Upstream providers can be added by installing an
                         appropriate Vim plugin.  For example, GitHub can be
                         supported by installing rhubarb.vim, available at
-                        <https://github.com/tpope/vim-rhubarb>.  (Native
-                        support for GitHub is currently included, but that is
-                        slated to be removed.)
+                        <https://github.com/tpope/vim-rhubarb>.
 
                         The hosting provider is determined by looking at the
                         remote for the current or specified branch and falls

plugin/fugitive.vim

@@ -70,6 +70,10 @@ endfunction
 
 let s:git_versions = {}
 
+function! s:git_command() abort
+  return get(g:, 'fugitive_git_command', g:fugitive_git_executable)
+endfunction
+
 function! fugitive#git_version(...) abort
   if !has_key(s:git_versions, g:fugitive_git_executable)
     let s:git_versions[g:fugitive_git_executable] = matchstr(system(g:fugitive_git_executable.' --version'), "\\S\\+\n")
@@ -112,11 +116,6 @@ function! s:define_commands() abort
   endfor
 endfunction
 
-augroup fugitive_utility
-  autocmd!
-  autocmd User Fugitive call s:define_commands()
-augroup END
-
 let s:abstract_prototype = {}
 
 " Section: Initialization
@@ -132,7 +131,12 @@ function! fugitive#extract_git_dir(path) abort
   if s:shellslash(a:path) =~# '^fugitive://.*//'
     return matchstr(s:shellslash(a:path), '\C^fugitive://\zs.\{-\}\ze//')
   endif
-  let root = s:shellslash(simplify(fnamemodify(a:path, ':p:s?[\/]$??')))
+  if isdirectory(a:path)
+    let path = fnamemodify(a:path, ':p:s?[\/]$??')
+  else
+    let path = fnamemodify(a:path, ':p:h:s?[\/]$??')
+  endif
+  let root = s:shellslash(resolve(path))
   let previous = ""
   while root !=# previous
     if root =~# '\v^//%([^/]+/?)?$'
@@ -184,6 +188,9 @@ function! fugitive#detect(path) abort
     let dir = fugitive#extract_git_dir(a:path)
     if dir !=# ''
       let b:git_dir = dir
+      if empty(fugitive#buffer().path())
+        silent! exe haslocaldir() ? 'lcd .' : 'cd .'
+      endif
     endif
   endif
   if exists('b:git_dir')
@@ -200,7 +207,7 @@ function! fugitive#detect(path) abort
       nnoremap <buffer> <silent> y<C-G> :call setreg(v:register, <SID>recall())<CR>
     endif
     let buffer = fugitive#buffer()
-    if expand('%:p') =~# '//'
+    if expand('%:p') =~# '://'
       call buffer.setvar('&path', s:sub(buffer.getvar('&path'), '^\.%(,|$)', ''))
     endif
     if stridx(buffer.getvar('&tags'), escape(b:git_dir, ', ')) == -1
@@ -213,6 +220,7 @@ function! fugitive#detect(path) abort
     endif
     try
       let [save_mls, &modelines] = [&mls, 0]
+      call s:define_commands()
       doautocmd User Fugitive
     finally
       let &mls = save_mls
@@ -271,6 +279,9 @@ function! s:configured_tree(git_dir) abort
       endif
     elseif filereadable(a:git_dir . '/gitdir')
       let worktree = fnamemodify(readfile(a:git_dir . '/gitdir')[0], ':h')
+      if worktree ==# '.'
+        unlet! worktree
+      endif
     endif
     if exists('worktree')
       let s:worktree_for_dir[a:git_dir] = worktree
@@ -287,6 +298,9 @@ endfunction
 function! s:repo_tree(...) dict abort
   if self.dir() =~# '/\.git$'
     let dir = self.dir()[0:-6]
+    if dir !~# '/'
+      let dir .= '/'
+    endif
   else
     let dir = s:configured_tree(self.git_dir)
   endif
@@ -344,7 +358,7 @@ function! s:repo_translate(spec) dict abort
   elseif filereadable(refs.'remotes/'.a:spec)
     return refs.'remotes/'.a:spec
   elseif filereadable(refs.'remotes/'.a:spec.'/HEAD')
-    return refs.'remotes/'.a:spec,'/HEAD'
+    return refs.'remotes/'.a:spec.'/HEAD'
   else
     try
       let ref = self.rev_parse(matchstr(a:spec,'[^:]*'))
@@ -375,12 +389,14 @@ endfunction
 call s:add_methods('repo',['dir','tree','bare','translate','head'])
 
 function! s:repo_git_command(...) dict abort
-  let git = g:fugitive_git_executable . ' --git-dir='.s:shellesc(self.git_dir)
+  let git = s:git_command() . ' --git-dir='.s:shellesc(self.git_dir)
   return git.join(map(copy(a:000),'" ".s:shellesc(v:val)'),'')
 endfunction
 
 function! s:repo_git_chomp(...) dict abort
-  return s:sub(system(call(self.git_command,a:000,self)),'\n$','')
+  let git = g:fugitive_git_executable . ' --git-dir='.s:shellesc(self.git_dir)
+  let output = git.join(map(copy(a:000),'" ".s:shellesc(v:val)'),'')
+  return s:sub(system(output),'\n$','')
 endfunction
 
 function! s:repo_git_chomp_in_tree(...) dict abort
@@ -457,7 +473,7 @@ endfunction
 call s:add_methods('repo',['dirglob','superglob'])
 
 function! s:repo_config(conf) dict abort
-  return matchstr(system(s:repo().git_command('config').' '.a:conf),"[^\r\n]*")
+  return matchstr(s:repo().git_chomp('config',a:conf),"[^\r\n]*")
 endfun
 
 function! s:repo_user() dict abort
@@ -469,8 +485,8 @@ endfun
 function! s:repo_aliases() dict abort
   if !has_key(self,'_aliases')
     let self._aliases = {}
-    for line in split(self.git_chomp('config','--get-regexp','^alias[.]'),"\n")
-      let self._aliases[matchstr(line,'\.\zs\S\+')] = matchstr(line,' \zs.*')
+    for line in split(self.git_chomp('config','-z','--get-regexp','^alias[.]'),"\1")
+      let self._aliases[matchstr(line, '\.\zs.\{-}\ze\n')] = matchstr(line, '\n\zs.*')
     endfor
   endif
   return self._aliases
@@ -481,9 +497,9 @@ call s:add_methods('repo',['config', 'user', 'aliases'])
 function! s:repo_keywordprg() dict abort
   let args = ' --git-dir='.escape(self.dir(),"\\\"' ")
   if has('gui_running') && !has('win32')
-    return g:fugitive_git_executable . ' --no-pager' . args . ' log -1'
+    return s:git_command() . ' --no-pager' . args . ' log -1'
   else
-    return g:fugitive_git_executable . args . ' show'
+    return s:git_command() . args . ' show'
   endif
 endfunction
 
@@ -694,14 +710,18 @@ function! s:Git(bang, args) abort
   if a:bang
     return s:Edit('edit', 1, a:args)
   endif
-  let git = g:fugitive_git_executable
+  let git = s:git_command()
   if has('gui_running') && !has('win32')
     let git .= ' --no-pager'
   endif
   let args = matchstr(a:args,'\v\C.{-}%($|\\@<!%(\\\\)*\|)@=')
   if exists(':terminal')
     let dir = s:repo().tree()
-    tabedit %
+    if expand('%') != ''
+      -tabedit %
+    else
+      -tabnew
+    endif
     execute 'lcd' fnameescape(dir)
     execute 'terminal' git args
   else
@@ -860,7 +880,9 @@ function! s:StageUndo() abort
   let hash = repo.git_chomp('hash-object', '-w', filename)
   if !empty(hash)
     if section ==# 'untracked'
-      call delete(s:repo().tree(filename))
+      call repo.git_chomp_in_tree('clean', '-f', '--', filename)
+    elseif section ==# 'unmerged'
+      call repo.git_chomp_in_tree('rm', '--', filename)
     elseif section ==# 'unstaged'
       call repo.git_chomp_in_tree('checkout', '--', filename)
     else
@@ -1055,13 +1077,14 @@ function! s:Commit(args, ...) abort
       else
         noautocmd silent execute '!'.command.' > '.outfile.' 2> '.errorfile
       endif
+      let error = v:shell_error
     finally
       execute cd.'`=dir`'
     endtry
     if !has('gui_running')
       redraw!
     endif
-    if !v:shell_error
+    if !error
       if filereadable(outfile)
         for line in readfile(outfile)
           echo line
@@ -1084,7 +1107,7 @@ function! s:Commit(args, ...) abort
         if bufname('%') == '' && line('$') == 1 && getline(1) == '' && !&mod
           execute 'keepalt edit '.s:fnameescape(msgfile)
         elseif a:args =~# '\%(^\| \)-\%(-verbose\|\w*v\)\>'
-          execute 'keepalt '.(tabpagenr()-1).'tabedit '.s:fnameescape(msgfile)
+          execute 'keepalt -tabedit '.s:fnameescape(msgfile)
         elseif s:buffer().type() ==# 'index'
           execute 'keepalt edit '.s:fnameescape(msgfile)
           execute (search('^#','n')+1).'wincmd+'
@@ -1115,7 +1138,7 @@ endfunction
 
 function! s:CommitComplete(A,L,P) abort
   if a:A =~ '^-' || type(a:A) == type(0) " a:A is 0 on :Gcommit -<Tab>
-    let args = ['-C', '-F', '-a', '-c', '-e', '-i', '-m', '-n', '-o', '-q', '-s', '-t', '-u', '-v', '--all', '--allow-empty', '--amend', '--author=', '--cleanup=', '--dry-run', '--edit', '--file=', '--include', '--interactive', '--message=', '--no-verify', '--only', '--quiet', '--reedit-message=', '--reuse-message=', '--signoff', '--template=', '--untracked-files', '--verbose']
+    let args = ['-C', '-F', '-a', '-c', '-e', '-i', '-m', '-n', '-o', '-q', '-s', '-t', '-u', '-v', '--all', '--allow-empty', '--amend', '--author=', '--cleanup=', '--dry-run', '--edit', '--file=', '--fixup=', '--include', '--interactive', '--message=', '--no-verify', '--only', '--quiet', '--reedit-message=', '--reuse-message=', '--signoff', '--squash=', '--template=', '--untracked-files', '--verbose']
     return filter(args,'v:val[0 : strlen(a:A)-1] ==# a:A')
   else
     return s:repo().superglob(a:A)
@@ -1205,7 +1228,7 @@ function! s:Merge(cmd, bang, args) abort
           \  !empty(s:repo().git_chomp('diff-files', '--diff-filter=U')))
       let &l:makeprg = g:fugitive_git_executable.' diff-files --name-status --diff-filter=U'
     else
-      let &l:makeprg = s:sub(g:fugitive_git_executable . ' ' . a:cmd .
+      let &l:makeprg = s:sub(s:git_command() . ' ' . a:cmd .
             \ (a:args =~# ' \%(--no-edit\|--abort\|-m\)\>' ? '' : ' --edit') .
             \ ' ' . a:args, ' *$', '')
     endif
@@ -1384,6 +1407,9 @@ function! s:Edit(cmd,bang,...) abort
       return 'redraw|echo '.string(':!'.git.' '.args)
     else
       let temp = resolve(tempname())
+      if has('win32')
+        let temp = fnamemodify(fnamemodify(temp, ':h'), ':p').fnamemodify(temp, ':t')
+      endif
       let s:temp_files[s:cpath(temp)] = { 'dir': buffer.repo().dir(), 'args': arglist }
       silent execute a:cmd.' '.temp
       if a:cmd =~# 'pedit'
@@ -1563,6 +1589,7 @@ function! s:Write(force,...) abort
 
   unlet! restorewinnr
   let zero = s:repo().translate(':0:'.path)
+  silent execute 'doautocmd BufWritePost' s:fnameescape(zero)
   for tab in range(1,tabpagenr('$'))
     for winnr in range(1,tabpagewinnr(tab,'$'))
       let bufnr = tabpagebuflist(tab)[winnr-1]
@@ -1625,7 +1652,7 @@ function! s:Dispatch(bang, args)
   try
     let b:current_compiler = 'git'
     let &l:errorformat = s:common_efm
-    let &l:makeprg = g:fugitive_git_executable . ' ' . a:args
+    let &l:makeprg = substitute(s:git_command() . ' ' . a:args, '\s\+$', '', '')
     execute cd fnameescape(s:repo().tree())
     if exists(':Make') == 2
       noautocmd Make
@@ -1774,13 +1801,17 @@ function! s:Diff(vert,keepfocus,...) abort
     let nr = bufnr('')
     execute 'leftabove '.vert.'split `=fugitive#buffer().repo().translate(s:buffer().expand('':2''))`'
     execute 'nnoremap <buffer> <silent> dp :diffput '.nr.'<Bar>diffupdate<CR>'
+    let nr2 = bufnr('')
     call s:diffthis()
     wincmd p
     execute 'rightbelow '.vert.'split `=fugitive#buffer().repo().translate(s:buffer().expand('':3''))`'
     execute 'nnoremap <buffer> <silent> dp :diffput '.nr.'<Bar>diffupdate<CR>'
+    let nr3 = bufnr('')
     call s:diffthis()
     wincmd p
     call s:diffthis()
+    execute 'nnoremap <buffer> <silent> d2o :diffget '.nr2.'<Bar>diffupdate<CR>'
+    execute 'nnoremap <buffer> <silent> d3o :diffget '.nr3.'<Bar>diffupdate<CR>'
     return post
   elseif len(args)
     let arg = join(args, ' ')
@@ -2000,6 +2031,9 @@ function! s:Blame(bang,line1,line2,count,args) abort
         endif
         let top = line('w0') + &scrolloff
         let current = line('.')
+        if has('win32')
+          let temp = fnamemodify(fnamemodify(temp, ':h'), ':p').fnamemodify(temp, ':t')
+        endif
         let s:temp_files[s:cpath(temp)] = { 'dir': s:repo().dir(), 'args': cmd }
         exe 'keepalt leftabove vsplit '.temp
         let b:fugitive_blamed_bufnr = bufnr
@@ -2018,6 +2052,7 @@ function! s:Blame(bang,line1,line2,count,args) abort
         if exists('+relativenumber')
           setlocal norelativenumber
         endif
+        let &l:statusline = '%{fugitive#blame_statusline('.bufnr('').')}%<'
         execute "vertical resize ".(s:linechars('.\{-\}\ze\s\+\d\+)')+1)
         nnoremap <buffer> <silent> <F1> :help fugitive-:Gblame<CR>
         nnoremap <buffer> <silent> g?   :help fugitive-:Gblame<CR>
@@ -2177,7 +2212,7 @@ endfunction
 
 function! s:RehighlightBlame() abort
   for [hash, cterm] in items(s:hash_colors)
-    if !empty(cterm) || has('gui_running')
+    if !empty(cterm) || has('gui_running') || has('termguicolors') && &termguicolors
       exe 'hi FugitiveblameHash'.hash.' guifg=#'.hash.get(s:hash_colors, hash, '')
     else
       exe 'hi link FugitiveblameHash'.hash.' Identifier'
@@ -2185,6 +2220,25 @@ function! s:RehighlightBlame() abort
   endfor
 endfunction
 
+function! fugitive#blame_statusline(nr) abort
+  if bufnr('%') != a:nr && !getwinvar(0, '&cursorbind')
+    return ''
+  endif
+  let line = getbufline(a:nr, line('.'))[0]
+  let hash = matchstr(line, '^\^\=\zs\x\{7}')
+  if hash =~# '^0*$'
+    return ''
+  endif
+  if type(getbufvar(a:nr, 'fugitive_blame_lookup')) != type({})
+    call setbufvar(a:nr, 'fugitive_blame_lookup', {})
+  endif
+  let lookup = getbufvar(a:nr, 'fugitive_blame_lookup')
+  if !has_key(lookup, hash)
+    let lookup[hash] = s:repo().git_chomp('log', '-1', hash, '--pretty=format:'.g:fugitive_summary_format)
+  endif
+  return get(lookup, hash, '')
+endfunction
+
 " Section: Gbrowse
 
 call s:command("-bar -bang -range=0 -nargs=* -complete=customlist,s:EditComplete Gbrowse :execute s:Browse(<bang>0,<line1>,<count>,<f-args>)")
@@ -2249,10 +2303,11 @@ function! s:Browse(bang,line1,count,...) abort
     if path =~# '^\.git/refs/remotes/.'
       if empty(remote)
         let remote = matchstr(path, '^\.git/refs/remotes/\zs[^/]\+')
-      endif
+        let branch = matchstr(path, '^\.git/refs/remotes/[^/]\+/\zs.\+')
+      else
         let merge = matchstr(path, '^\.git/refs/remotes/[^/]\+/\zs.\+')
-      let branch = ''
         let path = '.git/refs/heads/'.merge
+      endif
     elseif path =~# '^\.git/refs/heads/.'
       let branch = path[16:-1]
     elseif !exists('branch')
@@ -2289,9 +2344,14 @@ function! s:Browse(bang,line1,count,...) abort
 
     if empty(remote)
       let remote = '.'
-      let raw = s:repo().git_chomp('config','remote.origin.url')
+      let remote_for_url = 'origin'
     else
-      let raw = s:repo().git_chomp('config','remote.'.remote.'.url')
+      let remote_for_url = remote
+    endif
+    if fugitive#git_version() =~# '^[01]\.|^2\.[0-6]\.'
+      let raw = s:repo().git_chomp('config','remote.'.remote_for_url.'.url')
+    else
+      let raw = s:repo().git_chomp('remote','get-url',remote_for_url)
     endif
     if raw ==# ''
       let raw = remote
@@ -2315,13 +2375,13 @@ function! s:Browse(bang,line1,count,...) abort
     if empty(url) && raw ==# '.'
       call s:throw("Instaweb failed to start")
     elseif empty(url)
-      call s:throw('"'.remote."' is not a supported remote")
+      call s:throw("'".remote."' is not a supported remote")
     endif
 
     let url = s:gsub(url, '[ <>]', '\="%".printf("%02X",char2nr(submatch(0)))')
     if a:bang
       if has('clipboard')
-        let @* = url
+        let @+ = url
       endif
       return 'echomsg '.string(url)
     elseif exists(':Browse') == 2
@@ -2354,46 +2414,8 @@ function! s:github_url(opts, ...) abort
   if repo ==# ''
     return ''
   endif
-  let path = substitute(a:opts.path, '^/', '', '')
-  if index(domains, 'http://' . matchstr(repo, '^[^:/]*')) >= 0
-    let root = 'http://' . s:sub(repo,':','/')
-  else
-    let root = 'https://' . s:sub(repo,':','/')
-  endif
-  if path =~# '^\.git/refs/heads/'
-    let branch = a:opts.repo.git_chomp('config','branch.'.path[16:-1].'.merge')[11:-1]
-    if branch ==# ''
-      return root . '/commits/' . path[16:-1]
-    else
-      return root . '/commits/' . branch
-    endif
-  elseif path =~# '^\.git/refs/tags/'
-    return root . '/releases/tag/' . path[15:-1]
-  elseif path =~# '^\.git/refs/remotes/[^/]\+/.'
-    return root . '/commits/' . matchstr(path,'remotes/[^/]\+/\zs.*')
-  elseif path =~# '.git/\%(config$\|hooks\>\)'
-    return root . '/admin'
-  elseif path =~# '^\.git\>'
-    return root
-  endif
-  if a:opts.commit =~# '^\d\=$'
-    let commit = a:opts.repo.rev_parse('HEAD')
-  else
-    let commit = a:opts.commit
-  endif
-  if get(a:opts, 'type', '') ==# 'tree' || a:opts.path =~# '/$'
-    let url = substitute(root . '/tree/' . commit . '/' . path, '/$', '', 'g')
-  elseif get(a:opts, 'type', '') ==# 'blob' || a:opts.path =~# '[^/]$'
-    let url = root . '/blob/' . commit . '/' . path
-    if get(a:opts, 'line2') && a:opts.line1 == a:opts.line2
-      let url .= '#L' . a:opts.line1
-    elseif get(a:opts, 'line2')
-      let url .= '#L' . a:opts.line1 . '-L' . a:opts.line2
-    endif
-  else
-    let url = root . '/commit/' . commit
-  endif
-  return url
+  call s:warn('Install rhubarb.vim for GitHub support')
+  return 'https://github.com/tpope/vim-rhubarb'
 endfunction
 
 function! s:instaweb_url(opts) abort
@@ -2651,7 +2673,7 @@ function! s:BufReadObject() abort
       let b:fugitive_type = s:repo().git_chomp('cat-file','-t',hash)
     endif
     if b:fugitive_type !~# '^\%(tag\|commit\|tree\|blob\)$'
-      return "echoerr 'fugitive: unrecognized git type'"
+      return "echoerr ".string("fugitive: unrecognized git type '".b:fugitive_type."'")
     endif
     let firstline = getline('.')
     if !exists('b:fugitive_display_format') && b:fugitive_type != 'blob'
@@ -2686,7 +2708,7 @@ function! s:BufReadObject() abort
         if b:fugitive_display_format
           call s:ReplaceCmd(s:repo().git_command('cat-file',b:fugitive_type,hash))
         else
-          call s:ReplaceCmd(s:repo().git_command('show','--no-color','--pretty=format:tree %T%nparent %P%nauthor %an <%ae> %ad%ncommitter %cn <%ce> %cd%nencoding %e%n%n%s%n%n%b',hash))
+          call s:ReplaceCmd(s:repo().git_command('show','--no-color','--pretty=format:tree%x20%T%nparent%x20%P%nauthor%x20%an%x20<%ae>%x20%ad%ncommitter%x20%cn%x20<%ce>%x20%cd%nencoding%x20%e%n%n%s%n%n%b',hash))
           keepjumps call search('^parent ')
           if getline('.') ==# 'parent '
             silent keepjumps delete_
@@ -2838,7 +2860,7 @@ function! s:cfile() abort
       elseif getline('.') =~# '^#\trenamed:.* -> '
         let file = '/'.matchstr(getline('.'),' -> \zs.*')
         return [file]
-      elseif getline('.') =~# '^#\t[[:alpha:] ]\+: *.'
+      elseif getline('.') =~# '^#\t\(\k\| \)\+\p\?: *.'
         let file = '/'.matchstr(getline('.'),': *\zs.\{-\}\ze\%( ([^()[:digit:]]\+)\)\=$')
         return [file]
       elseif getline('.') =~# '^#\t.'
@@ -2895,7 +2917,7 @@ function! s:cfile() abort
         let ref = matchstr(getline('.'),'\x\{40\}')
         echoerr "warning: unknown context ".matchstr(getline('.'),'^\l*')
 
-      elseif getline('.') =~# '^[+-]\{3\} [ab/]'
+      elseif getline('.') =~# '^[+-]\{3\} [abciow12]\=/'
         let ref = getline('.')[4:]
 
       elseif getline('.') =~# '^[+-]' && search('^@@ -\d\+,\d\+ +\d\+,','bnW')
@@ -2909,7 +2931,7 @@ function! s:cfile() abort
           let lnum -= 1
         endwhile
         let offset += matchstr(getline(lnum), type.'\zs\d\+')
-        let ref = getline(search('^'.type.'\{3\} [ab]/','bnW'))[4:-1]
+        let ref = getline(search('^'.type.'\{3\} [abciow12]/','bnW'))[4:-1]
         let dcmds = [offset, 'normal!zv']
 
       elseif getline('.') =~# '^rename from '
@@ -2918,22 +2940,22 @@ function! s:cfile() abort
         let ref = 'b/'.getline('.')[10:]
 
       elseif getline('.') =~# '^@@ -\d\+,\d\+ +\d\+,'
-        let diff = getline(search('^diff --git \%(a/.*\|/dev/null\) \%(b/.*\|/dev/null\)', 'bcnW'))
+        let diff = getline(search('^diff --git \%([abciow12]/.*\|/dev/null\) \%([abciow12]/.*\|/dev/null\)', 'bcnW'))
         let offset = matchstr(getline('.'), '+\zs\d\+')
 
-        let dref = matchstr(diff, '\Cdiff --git \zs\%(a/.*\|/dev/null\)\ze \%(b/.*\|/dev/null\)')
-        let ref = matchstr(diff, '\Cdiff --git \%(a/.*\|/dev/null\) \zs\%(b/.*\|/dev/null\)')
+        let dref = matchstr(diff, '\Cdiff --git \zs\%([abciow12]/.*\|/dev/null\)\ze \%([abciow12]/.*\|/dev/null\)')
+        let ref = matchstr(diff, '\Cdiff --git \%([abciow12]/.*\|/dev/null\) \zs\%([abciow12]/.*\|/dev/null\)')
         let dcmd = 'Gdiff! +'.offset
 
-      elseif getline('.') =~# '^diff --git \%(a/.*\|/dev/null\) \%(b/.*\|/dev/null\)'
-        let dref = matchstr(getline('.'),'\Cdiff --git \zs\%(a/.*\|/dev/null\)\ze \%(b/.*\|/dev/null\)')
-        let ref = matchstr(getline('.'),'\Cdiff --git \%(a/.*\|/dev/null\) \zs\%(b/.*\|/dev/null\)')
+      elseif getline('.') =~# '^diff --git \%([abciow12]/.*\|/dev/null\) \%([abciow12]/.*\|/dev/null\)'
+        let dref = matchstr(getline('.'),'\Cdiff --git \zs\%([abciow12]/.*\|/dev/null\)\ze \%([abciow12]/.*\|/dev/null\)')
+        let ref = matchstr(getline('.'),'\Cdiff --git \%([abciow12]/.*\|/dev/null\) \zs\%([abciow12]/.*\|/dev/null\)')
         let dcmd = 'Gdiff!'
 
-      elseif getline('.') =~# '^index ' && getline(line('.')-1) =~# '^diff --git \%(a/.*\|/dev/null\) \%(b/.*\|/dev/null\)'
+      elseif getline('.') =~# '^index ' && getline(line('.')-1) =~# '^diff --git \%([abciow12]/.*\|/dev/null\) \%([abciow12]/.*\|/dev/null\)'
         let line = getline(line('.')-1)
-        let dref = matchstr(line,'\Cdiff --git \zs\%(a/.*\|/dev/null\)\ze \%(b/.*\|/dev/null\)')
-        let ref = matchstr(line,'\Cdiff --git \%(a/.*\|/dev/null\) \zs\%(b/.*\|/dev/null\)')
+        let dref = matchstr(line,'\Cdiff --git \zs\%([abciow12]/.*\|/dev/null\)\ze \%([abciow12]/.*\|/dev/null\)')
+        let ref = matchstr(line,'\Cdiff --git \%([abciow12]/.*\|/dev/null\) \zs\%([abciow12]/.*\|/dev/null\)')
         let dcmd = 'Gdiff!'
 
       elseif line('$') == 1 && getline('.') =~ '^\x\{40\}$'
@@ -2946,18 +2968,21 @@ function! s:cfile() abort
         let ref = ''
       endif
 
-      if myhash ==# ''
-        let ref = s:sub(ref,'^a/','HEAD:')
-        let ref = s:sub(ref,'^b/',':0:')
-        if exists('dref')
-          let dref = s:sub(dref,'^a/','HEAD:')
+      let prefixes = {
+            \ '1': '',
+            \ '2': '',
+            \ 'b': ':0:',
+            \ 'i': ':0:',
+            \ 'o': '',
+            \ 'w': ''}
+
+      if len(myhash)
+        let prefixes.a = myhash.'^:'
+        let prefixes.b = myhash.':'
       endif
-      else
-        let ref = s:sub(ref,'^a/',myhash.'^:')
-        let ref = s:sub(ref,'^b/',myhash.':')
+      let ref = substitute(ref, '^\(\w\)/', '\=get(prefixes, submatch(1), "HEAD:")', '')
       if exists('dref')
-          let dref = s:sub(dref,'^a/',myhash.'^:')
-        endif
+        let dref = substitute(dref, '^\(\w\)/', '\=get(prefixes, submatch(1), "HEAD:")', '')
       endif
 
       if ref ==# '/dev/null'
@@ -3065,7 +3090,7 @@ function! fugitive#foldtext() abort
       endif
     endfor
     if filename ==# ''
-      let filename = matchstr(getline(v:foldstart), '^diff .\{-\} a/\zs.*\ze b/')
+      let filename = matchstr(getline(v:foldstart), '^diff .\{-\} [abciow12]/\zs.*\ze [abciow12]/')
     endif
     if filename ==# ''
       let filename = getline(v:foldstart)[5:-1]