dovecot-auth-cli: Test invalid arguments handling

This patch adds a minor test to dovecot-auth-cli to verify that the
check for invalid number of arguments is working as expected.

It's mostly for consistency, as the utility is only used for testing
purposes.

cmd/dovecot-auth-cli/dovecot-auth-cli.go

@@ -1,7 +1,6 @@
 // CLI used for testing the dovecot authentication package.
 //
 // NOT for production use.
-// +build !coverage
 
 package main
 

cmd/dovecot-auth-cli/test.sh

@@ -16,6 +16,11 @@ else
 	go build $GOFLAGS -tags="$GOTAGS" dovecot-auth-cli.go
 fi
 
+if ! ./dovecot-auth-cli lalala 2>&1 | grep -q "invalid arguments"; then
+	echo "cli worked with invalid arguments"
+	exit 1
+fi
+
 for i in *.cmy; do
 	if ! chamuyero $i > $i.log 2>&1 ; then
 		echo "# Test $i failed, log follows"