[PATCH] maint: Tell git that *.py files should use python diff hunks

[Eric Blake <eblake@redhat.com>]

Git's default hunk pattern recognizer favors the C language, but it
also includes several built-in diff styles that give saner results in
other languages.  In particular, telling git to treat all .py files as
python changes the beginning of diff hunks as follows:

|  --- a/python/qemu/machine.py
|  +++ b/python/qemu/machine.py
| -@@ -337,12 +337,12 @@ class QEMUMachine:
| +@@ -337,12 +337,12 @@ def _post_shutdown(self) -> None:
|               self._qmp.close()

which makes it much easier to tell what function a patch is touching,
rather than a non-descript listing of what class contains the changes.

Sadly, our python files that don't use .py suffix (such as numerous
iotests) do not benefit from this glob.

Reported-by: John Snow <jsnow@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 .gitattributes | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitattributes b/.gitattributes
index 3d2fe2ecda8b..3e03ee01c0d9 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,2 +1,3 @@
 *.c.inc         diff=c
 *.h.inc         diff=c
+*.py            diff=python
-- 
2.30.1