Hmm...  Looks like a unified diff to me...
The text leading up to this was:
--------------------------
|diff -up st-0.8.4-ori/x.c st-0.8.4/x.c
|--- st-0.8.4-ori/x.c	2020-06-19 14:59:45.000000000 +0530
|+++ st-0.8.4/x.c	2020-07-20 03:39:56.260922736 +0530
--------------------------
Patching file x.c using Plan A...
Hunk #1 succeeded at 254.
Hunk #2 succeeded at 1102.
Hunk #3 succeeded at 1684.
done