diff --git a/test/integration/test_grammars.cc b/test/integration/test_grammars.cc
index e0d78eae..9f2763de 100644
--- a/test/integration/test_grammars.cc
+++ b/test/integration/test_grammars.cc
@@ -25,7 +25,7 @@ for (auto &language_name : test_languages) {
       it("fails with the correct error message", [&]() {
         TSCompileResult compile_result = ts_compile_grammar(grammar_json.c_str());
         string expected_error = read_file(expected_error_path);
-        AssertThat((void *)compile_result.error_message, !IsNull());
+        AssertThat((void *)compile_result.error_message, !Equals<void *>(nullptr));
         AssertThat(compile_result.error_message, Equals(expected_error));
       });
       return;
diff --git a/test/runtime/document_test.cc b/test/runtime/document_test.cc
index 054d7df3..138264bb 100644
--- a/test/runtime/document_test.cc
+++ b/test/runtime/document_test.cc
@@ -207,7 +207,7 @@ describe("Document", [&]() {
       AssertThat(ts_language_version(&language), !Equals<uint32_t>(TREE_SITTER_LANGUAGE_VERSION));
 
       ts_document_set_language(document, &language);
-      AssertThat(ts_document_language(document), IsNull());
+      AssertThat(ts_document_language(document), Equals<const TSLanguage *>(nullptr));
     });
   });
 
diff --git a/test/runtime/stack_test.cc b/test/runtime/stack_test.cc
index f7d2a9fd..4bdaa657 100644
--- a/test/runtime/stack_test.cc
+++ b/test/runtime/stack_test.cc
@@ -533,7 +533,7 @@ describe("Stack", [&]() {
     });
 
     it("allows the state to be retrieved", [&]() {
-      AssertThat(ts_stack_last_external_token(stack, 0), Equals(nullptr));
+      AssertThat(ts_stack_last_external_token(stack, 0), Equals<Tree *>(nullptr));
 
       ts_stack_set_last_external_token(stack, 0, trees[1]);
       AssertThat(ts_stack_last_external_token(stack, 0), Equals(trees[1]));