Add test/nothing_to_do.mk
diff --git a/test/nothing_to_do.mk b/test/nothing_to_do.mk
new file mode 100644
index 0000000..734abd8
--- /dev/null
+++ b/test/nothing_to_do.mk
@@ -0,0 +1,3 @@
+# TODO: Show something like "nothing to be done"
+
+Makefile: