api: Add unit test for null case of Sort::toString(). (#7865)

diff --git a/test/unit/api/cpp/sort_black.cpp b/test/unit/api/cpp/sort_black.cpp
index 108b2467093fcda0695613aee181d40ceeb71359..911a151e7595b57743a643221c74c154e8e1400d 100644 (file)
--- a/test/unit/api/cpp/sort_black.cpp
+++ b/test/unit/api/cpp/sort_black.cpp
@@ -626,5 +626,10 @@ TEST_F(TestApiBlackSort, sortScopedToString)
   ASSERT_EQ(uninterp_sort.toString(), name);
 }
 
+TEST_F(TestApiBlackSort, toString)
+{
+  ASSERT_NO_THROW(Sort().toString());
+}
+
 }  // namespace test
 }  // namespace cvc5