1 files changed, 2 insertions, 0 deletions
diff --git a/Makefile b/Makefile
index 6312cfa..55eb9f4 100644
--- a/Makefile
+++ b/Makefile
@@ -15,6 +15,8 @@ all: nthash.c
 check:
 	$(ECHO) -n "testing123" | ./nthash | \
 		$(GREP) -q '^3e678b266d1d449e531e92bec33b6d27$$'
+	$(ECHO) "testing123" | ./nthash 2>&1 | \
+		$(GREP) -q '^Warning: Input contains line break!$$'
 
 install:
 	$(INSTALL) -D -m0755 nthash $(DESTDIR)/usr/bin/nthash