ultimate-vim/sources_non_forked/vim-gitgutter/README.mkd

## vim-gitgutter

A Vim plugin which shows a git diff in the 'gutter' (sign column).  It shows which lines have been added, modified, or removed.  You can also preview, stage, and undo individual hunks; and stage partial hunks.  The plugin also provides a hunk text object.

The signs are always up to date and the plugin never saves your buffer.

Features:

* Shows signs for added, modified, and removed lines.
* Runs the diffs asynchronously where possible.
* Ensures signs are always up to date.
* Never saves the buffer.
* Quick jumping between blocks of changed lines ("hunks").
* Stage/undo/preview individual hunks.
* Previews highlight intra-line changes.
* Stage partial hunks.
* Provides a hunk text object.
* Diffs against index (default) or any commit.
* Allows folding all unchanged text.
* Provides fold text showing whether folded lines have been changed.
* Can load all hunk locations into quickfix list.
* Handles line endings correctly, even with repos that do CRLF conversion.
* Optional line highlighting.
* Optional line number highlighting. (Only available in Neovim 0.3.2 or higher)
* Fully customisable (signs, sign column, line (number) highlights, mappings, extra git-diff arguments, etc).
* Can be toggled on/off, globally or per buffer.
* Preserves signs from other plugins.
* Easy to integrate diff stats into status line; built-in integration with [vim-airline](https://github.com/bling/vim-airline/).
* Works with fish shell (in addition to the usual shells).

Constraints:

* Supports git only.  If you work with other version control systems, I recommend [vim-signify](https://github.com/mhinz/vim-signify).
* Relies on the `FocusGained` event.  If your terminal doesn't report focus events, either use something like [Terminus][] or set `let g:gitgutter_terminal_reports_focus=0`.  For tmux, `set -g focus-events on` in your tmux.conf.


### Screenshot

![screenshot](./screenshot.png?raw=true)

In the screenshot above you can see:

* Lines 183-184 are new.
* Lines 186-187 have been modified.
* The preview for the modified lines highlights changed regions within the line.


### Installation

Install using your favourite package manager, or use Vim's built-in package support.

Vim:

```
mkdir -p ~/.vim/pack/airblade/start
cd ~/.vim/pack/airblade/start
git clone https://github.com/airblade/vim-gitgutter.git
vim -u NONE -c "helptags vim-gitgutter/doc" -c q
```

Neovim:


```
mkdir -p ~/.config/nvim/pack/airblade/start
cd ~/.config/nvim/pack/airblade/start
git clone https://github.com/airblade/vim-gitgutter.git
nvim -u NONE -c "helptags vim-gitgutter/doc" -c q
```


### Windows

I recommend configuring vim-gitgutter with the full path to your git executable.  For example:

```viml
let g:gitgutter_git_executable = 'C:\Program Files\Git\bin\git.exe'
```

This is to avoid a problem which occurs if you have file named `git.*` (i.e. with any extension in `PATHEXT`) in your current folder.  `cmd.exe` prioritises the current folder over folders in `PATH` and will try to execute your file instead of the `git` binary.


### Getting started

When you make a change to a file tracked by git, the diff markers should appear automatically.  The delay is governed by vim's `updatetime` option; the default value is `4000`, i.e. 4 seconds, but I suggest reducing it to around 100ms (add `set updatetime=100` to your vimrc).

You can jump between hunks with `[c` and `]c`.  You can preview, stage, and undo hunks with `<leader>hp`, `<leader>hs`, and `<leader>hu` respectively.

You cannot unstage a staged hunk.


#### Activation

You can explicitly turn vim-gitgutter off and on (defaults to on):

* turn off with `:GitGutterDisable`
* turn on with `:GitGutterEnable`
* toggle with `:GitGutterToggle`.

To toggle vim-gitgutter per buffer:

* turn off with `:GitGutterBufferDisable`
* turn on with `:GitGutterBufferEnable`
* toggle with `:GitGutterBufferToggle`

You can turn the signs on and off (defaults to on):

* turn on with `:GitGutterSignsEnable`
* turn off with `:GitGutterSignsDisable`
* toggle with `:GitGutterSignsToggle`.

And you can turn line highlighting on and off (defaults to off):

* turn on with `:GitGutterLineHighlightsEnable`
* turn off with `:GitGutterLineHighlightsDisable`
* toggle with `:GitGutterLineHighlightsToggle`.

With Neovim 0.3.2 or higher, you can turn line number highlighting on and off (defaults to off):

* turn on with `:GitGutterLineNrHighlightsEnable`
* turn off with `:GitGutterLineNrHighlightsDisable`
* toggle with `:GitGutterLineNrHighlightsToggle`.

Note that if you have line highlighting on and signs off, you will have an empty sign column – more accurately, a sign column with invisible signs.  This is because line highlighting requires signs and Vim always shows the sign column even if the signs are invisible.

If you switch off both line highlighting and signs, you won't see the sign column.

To keep your Vim snappy, vim-gitgutter will suppress the signs when a file has more than 500 changes.  As soon as the number of changes falls below the limit vim-gitgutter will show the signs again.  You can configure the threshold with:

```viml
let g:gitgutter_max_signs = 500  " default value
```

#### Hunks

You can jump between hunks:

* jump to next hunk (change): `]c`
* jump to previous hunk (change): `[c`.

Both of those take a preceding count.

To set your own mappings for these, for example `]h` and `[h`:

```viml
nmap ]h <Plug>(GitGutterNextHunk)
nmap [h <Plug>(GitGutterPrevHunk)
```

You can load all your hunks into the quickfix list with `:GitGutterQuickFix`.  Note this ignores any unsaved changes in your buffers.

You can stage or undo an individual hunk when your cursor is in it:

* stage the hunk with `<Leader>hs` or
* undo it with `<Leader>hu`.

To stage part of an additions-only hunk by:

* either visually selecting the part you want and staging with your mapping, e.g. `<Leader>hs`;
* or using a range with the `GitGutterStageHunk` command, e.g. `:42,45GitGutterStageHunk`.

To stage part of any hunk:

* preview the hunk, e.g. `<Leader>hp`;
* move to the preview window, e.g. `:wincmd P`;
* delete the lines you do not want to stage;
* stage the remaining lines: either write (`:w`) the window or stage via `<Leader>hs` or `:GitGutterStageHunk`.

Note the above workflow is not possible if you have opted in to preview hunks with Vim's popup windows.

See the FAQ if you want to unstage staged changes.

The `.` command will work with both these if you install [repeat.vim](https://github.com/tpope/vim-repeat).

To set your own mappings for these, for example if you prefer `g`-based maps:

```viml
nmap ghs <Plug>(GitGutterStageHunk)
nmap ghu <Plug>(GitGutterUndoHunk)
```

And you can preview a hunk's changes with `<Leader>hp`.  The location of the preview window is configured with `g:gitgutter_preview_win_location` (default `'bo'`).  You can of course change this mapping, e.g:

```viml
nmap ghp <Plug>(GitGutterPreviewHunk)
```

A hunk text object is provided which works in visual and operator-pending modes.

- `ic` operates on all lines in the current hunk.
- `ac` operates on all lines in the current hunk and any trailing empty lines.

To re-map these, for example to `ih` and `ah`:

```viml
omap ih <Plug>(GitGutterTextObjectInnerPending)
omap ah <Plug>(GitGutterTextObjectOuterPending)
xmap ih <Plug>(GitGutterTextObjectInnerVisual)
xmap ah <Plug>(GitGutterTextObjectOuterVisual)
```

If you don't want vim-gitgutter to set up any mappings at all, use this:

```viml
let g:gitgutter_map_keys = 0
```

Finally, you can force vim-gitgutter to update its signs across all visible buffers with `:GitGutterAll`.

See the customisation section below for how to change the defaults.


### Folding

Use the `GitGutterFold` command to fold all unchanged lines, leaving just the hunks visible.  Use `zr` to unfold 3 lines of context above and below a hunk.

Execute `GitGutterFold` a second time to restore the previous view.

Use `gitgutter#fold#foldtext()` to augment the default `foldtext()` with an indicator of whether the folded lines have been changed.

```viml
set foldtext=gitgutter#fold#foldtext()
```

For a closed fold with changed lines:

```
Default foldtext():         +-- 45 lines: abcdef
gitgutter#fold#foldtext():  +-- 45 lines (*): abcdef
```

You can use `gitgutter#fold#is_changed()` in your own `foldtext` expression to find out whether the folded lines have been changed.


### Customisation

You can customise:

* The sign column's colours
* Whether or not the sign column is shown when there aren't any signs (defaults to no)
* How to handle non-gitgutter signs
* The signs' colours and symbols
* Line highlights
* Whether the diff is relative to the index (default) or working tree.
* The base of the diff
* Extra arguments for `git` when running `git diff`
* Extra arguments for `git diff`
* Key mappings
* Whether vim-gitgutter is on initially (defaults to on)
* Whether signs are shown (defaults to yes)
* Whether line highlighting is on initially (defaults to off)
* Whether line number highlighting is on initially (defaults to off)
* Whether vim-gitgutter runs asynchronously (defaults to yes)
* Whether to clobber or preserve non-gitgutter signs
* The priority of gitgutter's signs.
* Whether to use a floating/popup window for hunk previews

Please note that vim-gitgutter won't override any colours or highlights you've set in your colorscheme.


#### Sign column

By default vim-gitgutter will make the sign column look like the line number column.

To customise your sign column's background color, first tell vim-gitgutter to leave it alone:

```viml
let g:gitgutter_override_sign_column_highlight = 0
```

And then either update your colorscheme's `SignColumn` highlight group or set it in your vimrc:

```viml
highlight SignColumn ctermbg=whatever    " terminal Vim
highlight SignColumn guibg=whatever      " gVim/MacVim
```

By default the sign column will appear when there are signs to show and disappear when there aren't.  To always have the sign column, add to your vimrc:

```viml
" Vim 7.4.2201
set signcolumn=yes
```

GitGutter can preserve or ignore non-gitgutter signs.  For Vim v8.1.0614 and later you can set gitgutter's signs' priorities with `g:gitgutter_sign_priority`, so gitgutter defaults to clobbering other signs.  For Neovim v0.4.0 and later you can set an expanding sign column so gitgutter again defaults to clobbering other signs.  Otherwise, gitgutter defaults to preserving other signs.  You can configure this with:

```viml
let g:gitgutter_sign_allow_clobber = 1
```


#### Signs' colours and symbols

By default vim-gitgutter uses your colourscheme's `Diff*` highlight groups' foreground colours for the signs' foreground colours.  For example, your `DiffAdd` foreground colour will be used for the `+` sign's foreground colour.

The signs' background colours will all be set to the sign column's background colour.

If you don't like the default colours, you can either fix your colourscheme's `Diff*` highlights or configure your own `GitGutter*` highlight groups.  These groups are:

```viml
GitGutterAdd          " an added line             (default: links to DiffAdd)
GitGutterChange       " a changed line            (default: links to DiffChange)
GitGutterDelete       " at least one removed line (default: links to DiffDelete)
GitGutterChangeDelete " a changed line followed by at least one removed line (default: links to GitGutterChange)
```

You can either set these with `highlight GitGutterAdd {key}={arg}...` or link them to existing highlight groups with, say, `highlight link GitGutterAdd MyDiffAdd`.

To get vim-gitgutter's original colours (based on git-diff's colours in my terminal):

```viml
highlight GitGutterAdd    guifg=#009900 guibg=<X> ctermfg=2 ctermbg=<Y>
highlight GitGutterChange guifg=#bbbb00 guibg=<X> ctermfg=3 ctermbg=<Y>
highlight GitGutterDelete guifg=#ff2222 guibg=<X> ctermfg=1 ctermbg=<Y>
```

– where you would replace `<X>` and `<Y>` with the background colour of your `SignColumn` in the gui and the terminal respectively.  For example, with the solarized colorscheme and a dark background, `guibg=#073642` and `ctermbg=0`.

To customise the symbols, add the following to your `~/.vimrc`:

```viml
let g:gitgutter_sign_added = 'xx'
let g:gitgutter_sign_modified = 'yy'
let g:gitgutter_sign_removed = 'zz'
let g:gitgutter_sign_removed_first_line = '^^'
let g:gitgutter_sign_modified_removed = 'ww'
```


#### Line highlights

Similarly to the signs' colours, set up the following highlight groups in your colorscheme or `~/.vimrc`:

```viml
GitGutterAddLine          " default: links to DiffAdd
GitGutterChangeLine       " default: links to DiffChange
GitGutterDeleteLine       " default: links to DiffDelete
GitGutterChangeDeleteLine " default: links to GitGutterChangeLineDefault, i.e. DiffChange
```

For example, in some colorschemes the `DiffText` highlight group is easier to read than `DiffChange`.  You could use it like this:

```viml
highlight link GitGutterChangeLine DiffText
```


#### Line number highlights

NOTE: This feature requires Neovim 0.3.2 or higher.

Similarly to the signs' colours, set up the following highlight groups in your colorscheme or `~/.vimrc`:

```viml
GitGutterAddLineNr          " default: links to CursorLineNr
GitGutterChangeLineNr       " default: links to CursorLineNr
GitGutterDeleteLineNr       " default: links to CursorLineNr
GitGutterChangeDeleteLineNr " default: links to CursorLineNr
```

Maybe you think `CursorLineNr` is a bit annoying.  For example, you could use `Underlined` for this:

```viml
highlight link GitGutterChangeLineNr Underlined
```


#### Whether the diff is relative to the index or working tree

By default diffs are relative to the index.  How you can make them relative to the working tree:

```viml
let g:gitgutter_diff_relative_to = 'working_tree'
```


#### The base of the diff

By default buffers are diffed against the index.  However you can diff against any commit by setting:

```viml
let g:gitgutter_diff_base = '<commit SHA>'
```

This setting is ignored when the diffs are relative to the working tree.


#### Extra arguments for `git` when running `git diff`

If you want to pass extra arguments to `git` when running `git diff`, do so like this:

```viml
let g:gitgutter_git_args = '--git-dir-""'
```

#### Extra arguments for `git diff`

If you want to pass extra arguments to `git diff`, for example to ignore whitespace, do so like this:

```viml
let g:gitgutter_diff_args = '-w'
```

#### Key mappings

To disable all key mappings:

```viml
let g:gitgutter_map_keys = 0
```

See above for configuring maps for hunk-jumping and staging/undoing.


#### Use a custom `grep` command

If you use an alternative to grep, you can tell vim-gitgutter to use it here.

```viml
" Default:
let g:gitgutter_grep = 'grep'
```

#### To turn off vim-gitgutter by default

Add `let g:gitgutter_enabled = 0` to your `~/.vimrc`.


#### To turn off signs by default

Add `let g:gitgutter_signs = 0` to your `~/.vimrc`.


#### To turn on line highlighting by default

Add `let g:gitgutter_highlight_lines = 1` to your `~/.vimrc`.


#### To turn on line number highlighting by default

Add `let g:gitgutter_highlight_linenrs = 1` to your `~/.vimrc`.


#### To turn off asynchronous updates

By default diffs are run asynchronously.  To run diffs synchronously instead:

```viml
let g:gitgutter_async = 0
```


#### To use floating/popup windows for hunk previews

Add `let g:gitgutter_preview_win_floating = 1` to your vimrc.  Note that on Vim this prevents you staging (partial) hunks via the preview window.


### Extensions

#### Operate on every line in a hunk

You can map an operator to do whatever you want to every line in a hunk.

Let's say, for example, you want to remove trailing whitespace.

```viml
function! CleanUp(...)
  if a:0  " opfunc
    let [first, last] = [line("'["), line("']")]
  else
    let [first, last] = [line("'<"), line("'>")]
  endif
  for lnum in range(first, last)
    let line = getline(lnum)

    " clean up the text, e.g.:
    let line = substitute(line, '\s\+$', '', '')

    call setline(lnum, line)
  endfor
endfunction

nmap <silent> <Leader>x :set opfunc=CleanUp<CR>g@
```

Then place your cursor in a hunk and type `\xic` (assuming a leader of `\`).

Alternatively you could place your cursor in a hunk, type `vic` to select it, then `:call CleanUp()`.


#### Operate on every changed line in a file

You can write a command to do whatever you want to every changed line in a file.

```viml
function! GlobalChangedLines(ex_cmd)
  for hunk in GitGutterGetHunks()
    for lnum in range(hunk[2], hunk[2]+hunk[3]-1)
      let cursor = getcurpos()
      silent! execute lnum.a:ex_cmd
      call setpos('.', cursor)
    endfor
  endfor
endfunction

command -nargs=1 Glines call GlobalChangedLines(<q-args>)
```

Let's say, for example, you want to remove trailing whitespace from all changed lines:

```viml
:Glines s/\s\+$//
```


#### Cycle through hunks in all buffers

You can use `:GitGutterQuickFix` to load all hunks into the quickfix list.

Alternatively, given that`]c` and `[c` jump from one hunk to the next in the current buffer, you can use this code to jump to the next hunk no matter which buffer it's in.

```viml
function! NextHunkAllBuffers()
  let line = line('.')
  GitGutterNextHunk
  if line('.') != line
    return
  endif

  let bufnr = bufnr('')
  while 1
    bnext
    if bufnr('') == bufnr
      return
    endif
    if !empty(GitGutterGetHunks())
      normal! 1G
      GitGutterNextHunk
      return
    endif
  endwhile
endfunction

function! PrevHunkAllBuffers()
  let line = line('.')
  GitGutterPrevHunk
  if line('.') != line
    return
  endif

  let bufnr = bufnr('')
  while 1
    bprevious
    if bufnr('') == bufnr
      return
    endif
    if !empty(GitGutterGetHunks())
      normal! G
      GitGutterPrevHunk
      return
    endif
  endwhile
endfunction

nmap <silent> ]c :call NextHunkAllBuffers()<CR>
nmap <silent> [c :call PrevHunkAllBuffers()<CR>
```


### FAQ

> How can I turn off realtime updates?

Add this to your vim configuration (in an `/after/plugin` directory):

```viml
" .vim/after/plugin/gitgutter.vim
autocmd! gitgutter CursorHold,CursorHoldI
```

> I turned off realtime updates, how can I have signs updated when I save a file?

If you really want to update the signs when you save a file, add this to your vimrc:

```viml
autocmd BufWritePost * GitGutter
```

> Why can't I unstage staged changes?

This plugin is for showing changes between the buffer and the index (and staging/undoing those changes).  Unstaging a staged hunk would require showing changes between the index and HEAD, which is out of scope.

> Why are the colours in the sign column weird?

Your colorscheme is configuring the `SignColumn` highlight group weirdly.  Please see the section above on customising the sign column.

> Why are the colours in the preview window weird?

Probably because your colourscheme doesn't configure the `diff{Added,Changed,Removed}` highlight groups.  Try this in `after/syntax/diff.vim`:

```viml
highlight link diffAdded DiffAdd
highlight link diffChanged DiffChange
highlight link diffRemoved DiffDelete
```

> What happens if I also use another plugin which uses signs (e.g. Syntastic)?

You can configure whether GitGutter preserves or clobbers other signs using `g:gitgutter_sign_allow_clobber`.  Set to `1` to clobber other signs (default on Vim >= 8.1.0614 and NeoVim >= 0.4.0) or `0` to preserve them.


### Troubleshooting

#### When no signs are showing at all

Here are some things you can check:

* Try adding `let g:gitgutter_grep=''` to your vimrc.  If it works, the problem is grep producing non-plain output; e.g. ANSI escape codes or colours.
* Verify `:echo system("git --version")` succeeds.
* Verify your git config is compatible with the version of git returned by the command above.
* Verify your Vim supports signs (`:echo has('signs')` should give `1`).
* Verify your file is being tracked by git and has unstaged changes.

#### When the whole file is marked as added

* If you use zsh, and you set `CDPATH`, make sure `CDPATH` doesn't include the current directory.

#### When signs take a few seconds to appear

* Try reducing `updatetime`, e.g. `set updatetime=100`.

#### When signs don't update after focusing Vim

* Your terminal probably isn't reporting focus events.  Either try installing [Terminus][] or set `let g:gitgutter_terminal_reports_focus=0`.  For tmux, try `set -g focus-events on` in your tmux.conf.


### Shameless Plug

If this plugin has helped you, or you'd like to learn more about Vim, why not check out this screencast I wrote for PeepCode:

* [Smash Into Vim][siv]

This was one of PeepCode's all-time top three bestsellers and is now available at Pluralsight.

You can read reviews on my [website][airblade].


### Intellectual Property

Copyright Andrew Stewart, AirBlade Software Ltd.  Released under the MIT licence.


  [pathogen]: https://github.com/tpope/vim-pathogen
  [siv]: http://pluralsight.com/training/Courses/TableOfContents/smash-into-vim
  [airblade]: http://airbladesoftware.com/peepcode-vim
  [terminus]: https://github.com/wincent/terminus