[PATCH 09 of 10] py3: add a test to show `hg diff` works on Python 3

[Pulkit Goyal]

# HG changeset patch
# User Pulkit Goyal <7895pulkit at gmail.com>
# Date 1496264633 -19800
#      Thu Jun 01 02:33:53 2017 +0530
# Node ID ba24805f470b2e0967b8b279afacbbf3451fb8df
# Parent  a5498ec51c800ca99be644710b13b0e78a4997b6
py3: add a test to show `hg diff` works on Python 3

diff --git a/tests/test-py3-commands.t b/tests/test-py3-commands.t
--- a/tests/test-py3-commands.t
+++ b/tests/test-py3-commands.t
@@ -118,7 +118,13 @@
   $ $PYTHON3 $HGBIN add iota
   $ $PYTHON3 $HGBIN status
   A iota
-  $ $PYTHON3 $HGBIN diff --nodates
+  $ $PYTHON3 $HGBIN diff --nodates --git
+  diff --git a/iota b/iota
+  new file mode 100644
+  --- /dev/null
+  +++ b/iota
+  @@ -0,0 +1,1 @@
+  +This is the file 'iota'.
   $ $PYTHON3 $HGBIN commit --message 'commit performed in Python 3'
   $ $PYTHON3 $HGBIN status