1 files changed, 39 insertions, 0 deletions
diff --git a/util/random_test.cc b/util/random_test.cc
new file mode 100644
index 000000000..d1c555a0c
--- /dev/null
+++ b/util/random_test.cc
@@ -0,0 +1,39 @@
+#include "util/random.hh"
+
+#define BOOST_TEST_MODULE RandomTest
+#include <boost/test/unit_test.hpp>
+
+namespace util
+{
+namespace
+{
+
+BOOST_AUTO_TEST_CASE(returns_different_consecutive_numbers)
+{
+  rand_int_init(99);
+  const int first = rand_int(), second = rand_int(), third = rand_int();
+  // Sometimes you'll get the same number twice in a row, but generally the
+  // randomizer returns different numbers.
+  BOOST_CHECK(second != first || third != first);
+}
+
+BOOST_AUTO_TEST_CASE(returns_different_numbers_for_different_seeds)
+{
+  rand_int_init(1);
+  const int one1 = rand_int(), one2 = rand_int();
+  rand_int_init(2);
+  const int two1 = rand_int(), two2 = rand_int();
+  BOOST_CHECK(two1 != one1 || two2 != two1);
+}
+
+BOOST_AUTO_TEST_CASE(returns_same_sequence_for_same_seed)
+{
+  rand_int_init(1);
+  const int first = rand_int();
+  rand_int_init(1);
+  const int second = rand_int();
+  BOOST_CHECK_EQUAL(first, second);
+}
+
+} // namespace
+} // namespace util