From a21ca7e86e0daf8246db791c0084086b87cdc586 Mon Sep 17 00:00:00 2001
From: Maksim Odnoletkov <odnoletkov@mail.ru>
Date: Tue, 17 Sep 2019 23:17:27 +0100
Subject: [PATCH] Support X for submodules

Staged/[MD]:
Unstage and checkout superproject recorded version

Staged/A:
Noop. 'git rm -f' would be appropriate but it is destructive for
non-staged changes and hard to undo

Unstaged/A:
Noop. Hard to reproduce in practice, 'git status' doesn't handle it well
and hard to undo

Unstaged/[MD]:
Checkout superproject recorded version

Unstaged/[m?]:
Noop. Discarding submodules content changes is too complicated.
Workaround is to <CR> to submodule and discard from it's :Gstatus.
---
 autoload/fugitive.vim | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/autoload/fugitive.vim b/autoload/fugitive.vim
index cabf629..970233b 100644
--- a/autoload/fugitive.vim
+++ b/autoload/fugitive.vim
@@ -1654,12 +1654,12 @@ function! fugitive#BufReadStatus() abort
             let i += 1
             let file = output[i] . ' -> ' . matchstr(file, ' \zs.*')
           endif
+          let sub = matchstr(line, '^[12u] .. \zs....')
           if line[2] !=# '.'
-            call add(staged, {'type': 'File', 'status': line[2], 'filename': file})
+            call add(staged, {'type': 'File', 'status': line[2], 'filename': file, 'sub': sub})
           endif
           if line[3] !=# '.'
-            let sub = matchstr(line, '^[12u] .. \zs....')
-            call add(unstaged, {'type': 'File', 'status': get({'C':'M','M':'?','U':'?'}, matchstr(sub, 'S\.*\zs[CMU]'), line[3]), 'filename': file})
+            call add(unstaged, {'type': 'File', 'status': get({'C':'M','M':'?','U':'?'}, matchstr(sub, 'S\.*\zs[CMU]'), line[3]), 'filename': file, 'sub': sub})
           endif
         endif
         let i += 1
@@ -1697,12 +1697,12 @@ function! fugitive#BufReadStatus() abort
           let i += 1
         endif
         if line[0] !~# '[ ?!#]'
-          call add(staged, {'type': 'File', 'status': line[0], 'filename': files})
+          call add(staged, {'type': 'File', 'status': line[0], 'filename': files, 'sub': ''})
         endif
         if line[0:1] ==# '??'
           call add(untracked, {'type': 'File', 'status': line[1], 'filename': files})
         elseif line[1] !~# '[ !#]'
-          call add(unstaged, {'type': 'File', 'status': line[1], 'filename': files})
+          call add(unstaged, {'type': 'File', 'status': line[1], 'filename': files, 'sub': ''})
         endif
       endwhile
     endif
@@ -3074,6 +3074,20 @@ function! s:StageDelete(lnum1, lnum2, count) abort
       if empty(info.paths)
         continue
       endif
+      let sub = get(get(get(b:fugitive_files, info.section, {}), info.filename, {}), 'sub')
+      if sub =~# '^S'
+        if info.status ==# 'A'
+          continue
+        endif
+        if info.section ==# 'Staged'
+          call s:TreeChomp('reset', '--', info.paths[0])
+        endif
+        if info.status =~# '[MD]'
+          call s:TreeChomp('submodule', 'update', '--', info.paths[0])
+          call add(restore, ':Git -C ' . info.relative[0] . ' checkout -')
+        endif
+        continue
+      endif
       if info.status ==# 'D'
         let undo = 'Gremove'
       elseif info.paths[0] =~# '/$'