diff --git a/test/input.c b/test/input.c
index 9c005e6..7437962 100644
--- a/test/input.c
+++ b/test/input.c
@@ -1,8 +1,6 @@
 #include "greatest.h"
 #include "../input.h"
 
-#define s(x) {x, sizeof(x) - 1}
-
 TEST one_pass(void) {
 	struct libscomm_input in;
 	char s[] = "Arg 1\tArg \r\v\t!\n";
@@ -23,23 +21,36 @@ TEST one_pass(void) {
 	PASS();
 }
 
-#if 0
 TEST single_arg_too_large(void) {
 	struct libscomm_input in;
-	struct libscomm_inbuf b;
 	struct libscomm_line l;
 	char s[LIBSCOMM_MAXBUF + 12];
+	char *p;
 	size_t i;
+	int ostate;
 
 	for (i = 0; i < sizeof s; i++)
 		s[i] = 'a';
+	s[sizeof s - 2] = '\n';
+	s[sizeof s - 1] = 0;
+	p = s;
+
+	libscomm_reset(&in);
+	ASSERT_EQ(libscomm_read(&in, &p, &l), LIBSCOMM_OVERFLOW);
+	ASSERT_EQ(in.len, 0);
+
+	/* state values are opaque. */
+	ostate = in.state;
+	libscomm_reset(&in);
+	ASSERT_EQ(ostate, in.state);
+	PASS();
 }
-#endif
 
 GREATEST_MAIN_DEFS();
 
 int main(int argc, char *argv[]) {
 	GREATEST_MAIN_BEGIN();
 	RUN_TEST(one_pass);
+	RUN_TEST(single_arg_too_large);
 	GREATEST_MAIN_END();
 }