hunks: integrate coc-git extension

The coc-git extension to coc does show similar statistics as e.g.
gitgutter, therefore, integrate the coc-git interface into the hunk
extension.

closes #2094

CHANGELOG.md

@@ -10,6 +10,7 @@ This is the Changelog for the vim-airline project.
 - Improvements
   - git branch can also be displayed using [gina.vim](https://github.com/lambdalisue/gina.vim)
   - coc extensions can also show additional status messages
+  - [coc-git](https://github.com/neoclide/coc-git) extension integrated into hunks extension
 - Other
   - Introduce Vim script static analysis using [reviewdog](https://github.com/reviewdog/action-vint)
   - Added multiple Vim versions to unit tests using Travis CI

autoload/airline/extensions/hunks.vim

@@ -1,10 +1,10 @@
 " MIT License. Copyright (c) 2013-2019 Bailey Ling et al.
-" Plugin: vim-gitgutter, vim-signify, changesPlugin, quickfixsigns
+" Plugin: vim-gitgutter, vim-signify, changesPlugin, quickfixsigns, coc-git
 " vim: et ts=2 sts=2 sw=2
 
 scriptencoding utf-8
 
-if !get(g:, 'loaded_signify', 0) && !get(g:, 'loaded_gitgutter', 0) && !get(g:, 'loaded_changes', 0) && !get(g:, 'loaded_quickfixsigns', 0)
+if !get(g:, 'loaded_signify', 0) && !get(g:, 'loaded_gitgutter', 0) && !get(g:, 'loaded_changes', 0) && !get(g:, 'loaded_quickfixsigns', 0) && !empty(get(g:, 'coc_git_status',''))
   finish
 endif
 
@@ -19,6 +19,24 @@ function! s:get_hunks_signify()
   return []
 endfunction
 
+function! s:get_hunks_coc()
+  let hunks = get(b:, 'coc_git_status', '')
+  if empty(hunks)
+    return []
+  endif
+  let result = [0, 0, 0]
+  for val in split(hunks)
+    if val[0] is# '+'
+     let result[0] = val[1:] + 0
+    elseif val[0] is# '~'
+     let result[1] = val[1:] + 0
+    elseif val[0] is# '-'
+      let result[2] = val[1:] + 0
+    endif
+  endfor
+  return result
+endfunction
+
 function! s:is_branch_empty()
   return exists('*airline#extensions#branch#head') &&
         \ empty(get(b:, 'airline_head', ''))
@@ -53,9 +71,13 @@ function! airline#extensions#hunks#get_raw_hunks()
       let b:source_func = 's:get_hunks_changes'
     elseif exists('*quickfixsigns#vcsdiff#GetHunkSummary')
       let b:source_func = 'quickfixsigns#vcsdiff#GetHunkSummary'
+    elseif exists("g:coc_git_status")
+      let b:source_func = 's:get_hunks_coc'
     else
       let b:source_func = 's:get_hunks_empty'
     endif
+  else
+    let b:source_func = 's:get_hunks_empty'
   endif
   return {b:source_func}()
 endfunction
@@ -78,6 +100,7 @@ function! airline#extensions#hunks#get_hunks()
   let string = ''
   let winwidth = get(airline#parts#get('hunks'), 'minwidth', 100)
   if !empty(hunks)
+    " hunks should contain [added, changed, deleted]
     for i in [0, 1, 2]
       if (s:non_zero_only == 0 && airline#util#winwidth() > winwidth) || hunks[i] > 0
         let string .= printf('%s%s ', s:hunk_symbols[i], hunks[i])

doc/airline.txt

@@ -738,6 +738,7 @@ vim-gitgutter <https://github.com/airblade/vim-gitgutter>
 vim-signify <https://github.com/mhinz/vim-signify>
 changesPlugin <https://github.com/chrisbra/changesPlugin>
 quickfixsigns <https://github.com/tomtom/quickfixsigns_vim>
+coc-git <https://github.com/neoclide/coc-git>
 
 You can use `airline#extensions#hunks#get_raw_hunks()` to get the full hunks,
 without shortening. This allows for advanced customization, or a quick way of