--- /dev/null
+exec >&2
+
+a=$(cd fakesub2 && redo-whichdo d/snork)
+# if sh doesn't abort after the above, then it found a .do file as expected
+
+b=$(cat <<EOF
+d/snork.do
+d/default.do
+default.do
+EOF
+)
+
+if [ "$a" != "$b" ]; then
+ printf 'redo-whichdo mismatch.\n\ngot:\n%s\n\nexpected:\n%s\n' "$a" "$b"
+ exit 11
+fi