patch 8.0.0032
Problem:    Tests may change the input file when something goes wrong.
Solution:   Avoid writing the input file.
diff --git a/src/testdir/test67.in b/src/testdir/test67.in
index 08b4e37..e40cbab 100644
--- a/src/testdir/test67.in
+++ b/src/testdir/test67.in
@@ -24,7 +24,7 @@
 :call add(results, "#BufEnter#<buffer>: " . exists("#BufEnter#<buffer>"))
 :edit testfile2.test
 :call add(results, "#BufEnter#<buffer>: " . exists("#BufEnter#<buffer>"))
-:e test.out
+:e! test.out
 :call append(0, results)
 :$d
 :w