diffit - A git plugin for vim

Hi,

I am currently working on a git plugin for vim. My aim is for it to imitate much of git-gui's functionality. Right now, it is still closer to "add -p".

But I believe it's already useful. And since I'm new to vim scripting, it can use some testing.

To install, copy diffit.vim (attached to this email) to ~/.vim/plugin/diffit.vim .

To toggle diffit mode, use <Leader>d, where <Leader> is '\' by default.

Control keys:

 <Leader>d      toggle diffit mode
 s              stage hunk
 d              skip file

I hope you like it. Have fun!

Clemens
---

You can clone diffit from here.

git://repo.or.cz/diffit.git
http://github.com/drizzd/diffit.git

" ============================================================================
" File: diffit.vim
" Description: Show diff for current buffer
" Maintainer: Clemens Buchacher <[email protected]>
" License: GPLv2
"
" ============================================================================ if exists('loaded_diffit')
finish
end
let loaded_diffit = 1

let s:diffit_version = '0'

"for line continuation - i.e dont want C in &cpo
let s:old_cpo = &cpo
set cpo&vim

map <silent> <Leader>d :call <SID>Diffit()<CR>

function s:Error(msg)
echohl ErrorMsg
echon 'diffit: ' . a:msg
echohl None
endfunction

function s:Info(msg)
echon 'diffit: ' . a:msg
endfunction

function s:Die(msg)

	call s:Error('fatal: ' . a:msg)
	throw "diffit"

endfunction

function s:System(...)

	let out = system(join(a:000))
	if v:shell_error
		call s:Die(a:0 . ' failed: ' . out)
	end
	return out

endfunction

function s:Header()

	let header = []
	for n in range(1, line('$'))
			let l = getline(n)
			if l =~ '^diff --git ' ||
						\l =~ '^diff --cc ' ||
						\l =~ '^diff --combined ' ||
						\l =~ '^old mode ' ||
						\l =~ '^new mode ' ||
						\l =~ '^--- ' ||
						\l =~ '^+++ '
				call add(header, l)
				continue
			end
			if l !~ '^index '
				break
			end
	endfor
	return [header, n - 1]

endfunction

function s:Exit()
let view = b:view
bdelete
call winrestview(view)
endfunction

function s:Diffit()

	if exists('b:diffit') && b:diffit == 1
		call s:Exit()
		return
	end
	try
		call s:Diffit_init()
	catch /^diffit$/
		if exists('b:diffit') && b:diffit == 1
			call s:Exit()
		end
	endtry

endfunction

function s:Read_diff(pathlist)
let diff = tempname()
let path = ''
for path in a:pathlist
let out = s:System('git diff', '--', path, '>', diff) if getfsize(diff) > 0
break
end
endfor
return [diff, path]
endfunction

function s:Write_diff(diff, orig)

	setlocal modifiable
	silent 1,$delete _
	silent exe 'read ' . a:diff
	silent 1delete _
	setlocal nomodifiable

	if a:orig
		let orig_pos = b:view['lnum']
		let new_pos = s:Diffpos(orig_pos)
		let view = copy(b:view)
		let view['lnum'] = abs(new_pos)
		if new_pos > 0
			let view['topline'] += new_pos - orig_pos
			let view['topline'] = max([1, view['topline']])
		else
			let view['topline'] = -new_pos - 4
		end
		let view['curswant'] += 1
		let view['col'] += 1
		call winrestview(view)
	else
		call cursor(abs(s:Diffpos(0)), 1)
	end

endfunction

function s:Diffit_init()
update
let out = s:System('git rev-parse', '--is-inside-work-tree') if v:shell_error == 128 || split(out)[0] != 'true'
call s:Error('not inside work tree') return
elseif v:shell_error
call s:Error('git rev-parse failed: ' . out) return
end
let out = s:System('git diff', '--name-only')
let pathlist = split(out, '\n')
if empty(pathlist)
call s:Info('no changes')
return
end
let orig_path = bufname('%')
let k = index(pathlist, orig_path)
if k > 0
call remove(pathlist, k)
call insert(pathlist, orig_path, 0)
end
let [diff, path] = s:Read_diff(pathlist)
let orig = path == orig_path
if getfsize(diff) == 0
call s:Info('no changes')
return
end

let view = winsaveview()
silent! exe 'edit ' . tempname()
let b:pathlist = pathlist
let b:view = view
let b:diffit = 1
setf git-diff
setlocal noswapfile
setlocal buftype=nofile
setlocal nowrap
setlocal foldcolumn=0
setlocal nobuflisted

iabc <buffer>

nnoremap <silent> <buffer> s :call <SID>Stage_hunk(line('.'))<CR> nnoremap <silent> <buffer> d :call <SID>Next_diff()<CR>

call s:Write_diff(diff, orig)
echon '"' . path . '"'
endfunction

function s:Next_diff()
call remove(b:pathlist, 0)
let [diff, path] = s:Read_diff(b:pathlist) if getfsize(diff) > 0
call s:Write_diff(diff, 0) echon '"' . path . '"'
else
call s:Exit()
end
endfunction

function s:Diffpos(orig_pos)
let diffpos = -1
let hunk_start = 1
let hunk_end = 1
call cursor(1, 1)
while search('^@@', 'W') > 0
let [start, length] = matchlist(getline('.'),
\'^@@ -[0-9]*,[0-9]* +\%(\([0-9]*\),\)\?\([0-9]*\)')[1:2]
if empty(start)
let start = 1
end
if diffpos < 0
let diffpos = -line('.')
end
if start > a:orig_pos
break
end
let diffpos = line('.')
let hunk_start = start
let hunk_end = hunk_start + length - 1
endwhile
if diffpos < 0
return diffpos
end
let pos = hunk_start - 1
let target_pos = min([a:orig_pos, hunk_end])
while diffpos < line('$')
if getline(diffpos) =~ '^-'
let diffpos += 1
continue
end
if pos >= target_pos
break
end
let diffpos += 1
let pos += 1
endwhile

if getline(diffpos) =~ '^-'
return -last
else
return diffpos
end
endfunction

function s:Stage_hunk(pos)
call cursor(a:pos, 1)
let h_start = search('^@@', 'bcW')
if h_start == 0
return
end
call cursor(h_start, 1)
let h_end = search('^@@', 'nW')-1
if h_end < 0
let h_end = line('$')
end
let h_range = h_start . ',' . h_end

let [patch, header_end] = s:Header()
call extend(patch, getline(h_start, h_end))
let patchfile = tempname()
call writefile(patch, patchfile)
let out = s:System('git apply', '--cached', '--whitespace=nowarn', patchfile)

setlocal modifiable
silent exe h_range . 'delete _'
setlocal nomodifiable
if line('$') == header_end
call s:Next_diff()
return
end
endfunction

let &cpo = s:old_cpo

Clemens, were you aware that there are already a couple of Git plug-ins for Vim? Of these, the most advanced one currently is almost certainly Fugitive:

http://github.com/tpope/vim-fugitive

Cheers,
Wincent

Hi Wincent,

The git plugins I am aware of, including vim-fugitive, mostly implement git commands to be executed from vim. I find that utterly useless, since I can already do that from the command line.

What I can not do from the command line is staging hunks and lines interactively, possibly interrupted by a quick fix to a change. This is what I would use git-gui for, only it does not integrate very well with my vim + cmdline centric workflow.

Here's my TODO list:

- handle file mode changes

- navigation (prev/next hunk/file)

- stage individual lines and (virtual) range

- unstage changes

- file browser (modified, staged, untracked)

- prepare commit message

- git add -e?

If existing plugins already implement these features, then I have missed it, and I will be happy to use or improve them instead.

As for diffing, some of the existing plugins implement side-by-side, or even inline diff, using the vimdiff feature. I prefer the native git-diff format, however.

Cheers,
Clemens

Could you add information about 'diffit' to "Interfaces, Frontends And Tools" page on Git Wiki:
https://git.wiki.kernel.org/index.php/InterfacesFrontendsAndTools
in the 'Editors and IDE integration' section?

Thanks in advance.

Jakub Narebski
Poland
ShadeHawk on #git