tools: add cpplint rule for NULL usage

This commit is a suggestion for adding a rule for NULL usages in the
code base. This will currently report a number of errors which could be
ignored using // NOLINT (readability/null_usage)

PR-URL: https://github.com/nodejs/node/pull/17373
Reviewed-By: Jon Moss <me@jonathanmoss.me>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Timothy Gu <timothygu99@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>

3 files changed, 5 insertions, 0 deletions

diff --git a/test/addons-napi/7_factory_wrap/binding.cc b/test/addons-napi/7_factory_wrap/binding.cc
index c8fca4d536..d981324578 100644
--- a/test/addons-napi/7_factory_wrap/binding.cc
+++ b/test/addons-napi/7_factory_wrap/binding.cc
@@ -16,6 +16,7 @@ napi_value Init(napi_env env, napi_value exports) {
   NAPI_CALL(env, MyObject::Init(env));
 
   NAPI_CALL(env,
+      // NOLINTNEXTLINE (readability/null_usage)
       napi_create_function(env, "exports", -1, CreateObject, NULL, &exports));
   return exports;
 }
diff --git a/test/addons-napi/test_make_callback/binding.cc b/test/addons-napi/test_make_callback/binding.cc
index 4b0537ca07..952dfcc1cb 100644
--- a/test/addons-napi/test_make_callback/binding.cc
+++ b/test/addons-napi/test_make_callback/binding.cc
@@ -8,6 +8,7 @@ napi_value MakeCallback(napi_env env, napi_callback_info info) {
   const int kMaxArgs = 10;
   size_t argc = kMaxArgs;
   napi_value args[kMaxArgs];
+  // NOLINTNEXTLINE (readability/null_usage)
   NAPI_CALL(env, napi_get_cb_info(env, info, &argc, args, NULL, NULL));
 
   NAPI_ASSERT(env, argc > 0, "Wrong number of arguments");
@@ -47,6 +48,7 @@ napi_value MakeCallback(napi_env env, napi_callback_info info) {
 napi_value Init(napi_env env, napi_value exports) {
   napi_value fn;
   NAPI_CALL(env, napi_create_function(
+      // NOLINTNEXTLINE (readability/null_usage)
       env, NULL, NAPI_AUTO_LENGTH, MakeCallback, NULL, &fn));
   NAPI_CALL(env, napi_set_named_property(env, exports, "makeCallback", fn));
   return exports;
diff --git a/test/addons-napi/test_make_callback_recurse/binding.cc b/test/addons-napi/test_make_callback_recurse/binding.cc
index 714e44773d..b99c583d31 100644
--- a/test/addons-napi/test_make_callback_recurse/binding.cc
+++ b/test/addons-napi/test_make_callback_recurse/binding.cc
@@ -7,6 +7,7 @@ namespace {
 napi_value MakeCallback(napi_env env, napi_callback_info info) {
   size_t argc = 2;
   napi_value args[2];
+  // NOLINTNEXTLINE (readability/null_usage)
   NAPI_CALL(env, napi_get_cb_info(env, info, &argc, args, NULL, NULL));
 
   napi_value recv = args[0];
@@ -21,6 +22,7 @@ napi_value MakeCallback(napi_env env, napi_callback_info info) {
 napi_value Init(napi_env env, napi_value exports) {
   napi_value fn;
   NAPI_CALL(env, napi_create_function(
+      // NOLINTNEXTLINE (readability/null_usage)
       env, NULL, NAPI_AUTO_LENGTH, MakeCallback, NULL, &fn));
   NAPI_CALL(env, napi_set_named_property(env, exports, "makeCallback", fn));
   return exports;