1 files changed, 4 insertions, 0 deletions
diff --git a/test/test_env.c b/test/test_env.c
index fcc45c53..651bf8c9 100644
--- a/test/test_env.c
+++ b/test/test_env.c
@@ -46,6 +46,10 @@ test_env(void)
 
   serd_env_set_prefix(env, prefix, eg);
 
+  assert(!serd_env_base_uri(NULL));
+  assert(!serd_env_expand(NULL, NULL));
+  assert(!serd_env_qualify(NULL, foo_u));
+
   assert(!serd_env_base_uri(env));
   assert(!serd_env_set_base_uri(env, SERD_EMPTY_STRING()));
   assert(!serd_env_base_uri(env));