Make test scripts fail if result files are created

tools/test/h5diff/h5diff_plugin.sh.in

@@ -242,6 +242,8 @@ TOOLTEST() {
         # Create the expect file if it doesn't yet exist.
         echo " CREATED"
         cp $actual $expect
+        echo "    Expected result (*.ddl) missing"
+        nerrors="`expr $nerrors + 1`"
     elif $CMP $expect $actual; then
         echo " PASSED"
     elif test $h5haveexitcode = 'yes' -a -z "$pmode"; then