test: cover native-Windows platform detection without uname (#145)

c/tests/test_makefile_platform.py

@@ -0,0 +1,34 @@
+import os
+import shutil
+import subprocess
+import unittest
+from pathlib import Path
+
+
+C_DIR = Path(__file__).resolve().parents[1]
+MAKE = shutil.which("make")
+
+
+@unittest.skipUnless(MAKE, "make is required")
+class MakefilePlatformTests(unittest.TestCase):
+    def test_windows_nt_without_uname_selects_mingw_build(self):
+        env = os.environ.copy()
+        env["OS"] = "Windows_NT"
+        env["PATH"] = ""
+
+        result = subprocess.run(
+            [MAKE, "--no-print-directory", "-B", "-n", "glm"],
+            cwd=C_DIR,
+            env=env,
+            text=True,
+            capture_output=True,
+            check=True,
+        )
+
+        self.assertIn("-o glm.exe", result.stdout)
+        self.assertIn("-fopenmp", result.stdout)
+        self.assertIn("-static", result.stdout)
+
+
+if __name__ == "__main__":
+    unittest.main()