/usr/lib/flatpak/installed-tests/flatpak-builder/data1.patch is in flatpak-builder-tests 0.10.9-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 | --- data1 2017-04-24 09:24:02.861719643 +0200
+++ data1.mod 2017-04-24 09:35:44.589157410 +0200
@@ -1 +1 @@
-Some data1
+Some modified data1
|