Enable clang-tidy as a sanity check, fix up all known failures

2 files changed, 2 insertions, 2 deletions

diff --git a/test/cpp/interop/http2_client.cc b/test/cpp/interop/http2_client.cc
index 1e04e57d09..2de7abcf17 100644
--- a/test/cpp/interop/http2_client.cc
+++ b/test/cpp/interop/http2_client.cc
@@ -217,7 +217,7 @@ int main(int argc, char** argv) {
         "goaway",         "max_streams",      "ping",
         "rst_after_data", "rst_after_header", "rst_during_data"};
     char* joined_testcases =
-        gpr_strjoin_sep(testcases, GPR_ARRAY_SIZE(testcases), "\n", NULL);
+        gpr_strjoin_sep(testcases, GPR_ARRAY_SIZE(testcases), "\n", nullptr);
 
     gpr_log(GPR_ERROR, "Unsupported test case %s. Valid options are\n%s",
             FLAGS_test_case.c_str(), joined_testcases);
diff --git a/test/cpp/interop/stress_test.cc b/test/cpp/interop/stress_test.cc
index 991fc88ad2..028ff11b20 100644
--- a/test/cpp/interop/stress_test.cc
+++ b/test/cpp/interop/stress_test.cc
@@ -230,7 +230,7 @@ int main(int argc, char** argv) {
   log_level = FLAGS_log_level;
   gpr_set_log_function(TestLogFunction);
 
-  srand(time(NULL));
+  srand(time(nullptr));
 
   // Parse the server addresses
   std::vector<grpc::string> server_addresses;