diff --git a/tests/decheck b/tests/decheck
new file mode 100755
index 0000000..7e1be39
--- /dev/null
+++ b/tests/decheck
@@ -0,0 +1,3 @@
+#!/bin/sh
+# Turn a non-oldstyle checkfile on stdin into an equivalent log on stdout.
+sed -n -e '/> /s///p'