diff --git a/native/test.cpp b/native/test.cpp
index 826d973..44fad1b 100644
--- a/native/test.cpp
+++ b/native/test.cpp
@@ -4,7 +4,7 @@
 
 using namespace std;
 
-bool run(int method, char* buffer, size_t buffer_length) {
+bool run(compression_codec method, char* buffer, size_t buffer_length) {
     int32_t len{0};
     bool ok = iron_compress(true, method, buffer, buffer_length, nullptr, &len, compression_level::best);
 
@@ -27,31 +27,36 @@ bool run(int method, char* buffer, size_t buffer_length) {
 
 TEST(Roundtrip, Snappy_1) {
     char bytes[] = {'a', 'b', 'c'};
-    EXPECT_TRUE(run(1, bytes, 3));
+    EXPECT_TRUE(run(compression_codec::snappy, bytes, 3));
 }
 
 TEST(Roundtrip, Zstd_2) {
     char bytes[] = {'a', 'b', 'c'};
-    EXPECT_TRUE(run(2, bytes, 3));
+    EXPECT_TRUE(run(compression_codec::zstd, bytes, 3));
 }
 
 TEST(Roundtrip, Gzip_3) {
     EXPECT_FALSE(iron_is_supported(compression_codec::gzip));
+    EXPECT_FALSE(iron_compress(true, compression_codec::gzip,
+        nullptr, 0,
+        nullptr, nullptr,
+        compression_level::best));
+
     //char bytes[] = {'a', 'b', 'c'};
     //EXPECT_TRUE(run(3, bytes, 3));
 }
 
 TEST(Roundtrip, Brotli_4) {
     char bytes[] = {'a', 'b', 'c'};
-    EXPECT_TRUE(run(4, bytes, 3));
+    EXPECT_TRUE(run(compression_codec::brotli, bytes, 3));
 }
 
 TEST(Roundtrip, Lzo_5) {
     char bytes[] = {'a', 'b', 'c'};
-    EXPECT_TRUE(run(5, bytes, 3));
+    EXPECT_TRUE(run(compression_codec::lzo, bytes, 3));
 }
 
 TEST(Roundtrip, LZ4_6) {
     char bytes[] = {'a', 'b', 'c'};
-    EXPECT_TRUE(run(6, bytes, 3));
+    EXPECT_TRUE(run(compression_codec::lz4, bytes, 3));
 }
\ No newline at end of file