* util/grub-script-check.c: Fail on scripts containing no

commands, to guard against corrupted grub-mkconfig setups that
produce no useful output.
* tests/grub_script_no_commands.in: New test.
* Makefile.util.def (grub_script_no_commands): Add.
Reported by Hans Putter.  Fixes Debian bug #713886.

tests/grub_script_no_commands.in

@@ -0,0 +1,21 @@
+#! /bin/sh
+set -e
+
+# grub-script-check refuses to pass a file with no commands; this usually
+# indicates a bug in the code generating that file.
+
+@builddir@/grub-script-check <<EOF && exit 1
+
+EOF
+
+@builddir@/grub-script-check <<EOF && exit 1
+# comment
+EOF
+
+@builddir@/grub-script-check <<EOF && exit 1
+# comment 1
+# comment 2
+
+EOF
+
+exit 0