1 files changed, 62 insertions, 0 deletions
diff --git a/test_util.c b/test_util.c
new file mode 100644
index 0000000..81c3db7
--- /dev/null
+++ b/test_util.c
@@ -0,0 +1,62 @@
+#include <string.h>
+
+#include "unity.h"
+#include "util.h"
+
+void setUp(){};
+void tearDown(){};
+
+/* blank_to_eol should pad a buffer with spaces as far as it can, after an
+ * existing string therein, without overrunning, while still terminating */
+void test_blank_to_eol_happy(void)
+{
+	char buf[11] = "hello";
+	blank_to_eol(buf, sizeof(buf));
+	TEST_ASSERT_EQUAL_STRING("hello     ", buf);
+}
+
+/* blanking an empty string to end of buffer should fill entire buffer with
+ * spaces until the last byte, which should be null terminator */
+void test_blank_to_eol_empty(void)
+{
+	char buf[5] = "";
+	blank_to_eol(buf, sizeof(buf));
+	TEST_ASSERT_EQUAL_STRING("    ", buf);
+}
+
+/* blanking should not overrun the specified buffer size at all */
+void test_blank_to_eol_no_overrun(void)
+{
+	char buf[20] = {
+		'h', 'e', 'l', 'l', 'o', '\0',
+		'b', 'l', 'a', 'h',
+		'm', 'a', 'g', 'i', 'c', '\0'
+	};
+	blank_to_eol(buf, 10);
+	const char *expect = "hello    ";
+	TEST_ASSERT_EQUAL_STRING(expect, buf);
+	TEST_ASSERT_EQUAL_STRING("magic", &buf[strlen(expect)+1]);
+}
+
+/* blanking a buffer which already has no '\0' within it should result in the
+ * buffer being terminated, truncating contents minimally as necessary to fit
+ * a '\0' */
+void test_blank_to_eol_overrun(void)
+{
+	char buf[20] = "hello, world!";
+	blank_to_eol(buf, 6);
+	TEST_ASSERT_EQUAL_STRING("hello", buf);
+	/* also check that the buffer wasn't clobbered beyond its end. Note this
+	 * doesn't test OOB reads, only writes */
+	TEST_ASSERT_EQUAL_STRING(" world!", &buf[6]);
+}
+
+int main(void)
+{
+	UNITY_BEGIN();
+	RUN_TEST(test_blank_to_eol_happy);
+	RUN_TEST(test_blank_to_eol_empty);
+	RUN_TEST(test_blank_to_eol_no_overrun);
+	RUN_TEST(test_blank_to_eol_overrun);
+	return UNITY_END();
+}