partial staging at the end of a file with no trailing newline

[x-yuri]

Steps to reproduce:

git init

echo -n 'line 1
line 2
line 3' > a
git add a
git commit -m a

echo 'line 1
line 2
line 2.2
line 3' > a

Run vim/neovim, open the status buffer:

Head: master
Push: origin/master

Unstaged (1)
M a
@@ -1,3 +1,4 @@
 line 1
 line 2
-line 3
\ No newline at end of file
+line 2.2
+line 3

And try to stage only the "line 2.2" line (visually select and press s):

fugitive: error: patch failed: a:1^@error: a: patch does not apply

The patch it tries to apply:

diff --git a a
index 8cf2f17..58c1de1 100644
--- a
+++ a
@@ -1,3 +1,4 @@
 line 1
 line 2
 line 3
+line 2.2

0000000   d   i   f   f       -   -   g   i   t       a       a  \n   i
0000020   n   d   e   x       8   c   f   2   f   1   7   .   .   5   8
0000040   c   1   d   e   1       1   0   0   6   4   4  \n   -   -   -
0000060       a  \n   +   +   +       a  \n   @   @       -   1   ,   3
0000100       +   1   ,   4       @   @  \n       l   i   n   e       1
0000120  \n       l   i   n   e       2  \n       l   i   n   e       3
0000140  \n   +   l   i   n   e       2   .   2  \n
0000153

Vim 8.2, Neovim 0.4.4, Fugitive 4189bdb, Git 2.28.0.