test: add tests for c_float and c_double

Author: MrIndeciso

test/scripts/types_unit_test.py

@@ -5,9 +5,11 @@
 #
 
 import ctypes
+import math
+import struct as pystruct
 import unittest
 
-from libdestruct import c_int, c_long, c_str, c_uint, inflater, struct, ptr, ptr_to_self
+from libdestruct import c_int, c_long, c_str, c_uint, c_float, c_double, inflater, struct, ptr, ptr_to_self
 
 
 class ObjFromBytesTest(unittest.TestCase):
@@ -104,6 +106,82 @@ class test_t(struct):
         self.assertIn("0x0", s)
 
 
+class FloatTest(unittest.TestCase):
+    """c_float and c_double types."""
+
+    def test_c_float_read(self):
+        memory = pystruct.pack("<f", 3.14)
+        obj = c_float.from_bytes(memory)
+        self.assertAlmostEqual(obj.value, 3.14, places=5)
+
+    def test_c_double_read(self):
+        memory = pystruct.pack("<d", 2.718281828)
+        obj = c_double.from_bytes(memory)
+        self.assertAlmostEqual(obj.value, 2.718281828, places=8)
+
+    def test_c_float_write(self):
+        memory = bytearray(4)
+        lib = inflater(memory)
+        obj = lib.inflate(c_float, 0)
+
+        obj.value = 1.5
+        self.assertAlmostEqual(obj.value, 1.5)
+        self.assertEqual(memory, pystruct.pack("<f", 1.5))
+
+    def test_c_float_to_bytes_round_trip(self):
+        original = pystruct.pack("<f", -42.5)
+        obj = c_float.from_bytes(original)
+        self.assertEqual(obj.to_bytes(), original)
+
+    def test_c_double_to_bytes_round_trip(self):
+        original = pystruct.pack("<d", 123456.789)
+        obj = c_double.from_bytes(original)
+        self.assertEqual(obj.to_bytes(), original)
+
+    def test_c_float_in_struct(self):
+        class test_t(struct):
+            x: c_float
+            y: c_float
+
+        memory = pystruct.pack("<ff", 1.0, 2.0)
+        test = test_t.from_bytes(memory)
+        self.assertAlmostEqual(test.x.value, 1.0)
+        self.assertAlmostEqual(test.y.value, 2.0)
+
+    def test_c_float_size(self):
+        self.assertEqual(c_float.size, 4)
+
+    def test_c_double_size(self):
+        self.assertEqual(c_double.size, 8)
+
+    def test_c_float_special_values(self):
+        for val in [0.0, float("inf"), float("-inf")]:
+            memory = pystruct.pack("<f", val)
+            obj = c_float.from_bytes(memory)
+            self.assertEqual(obj.value, val)
+
+        # NaN
+        memory = pystruct.pack("<f", float("nan"))
+        obj = c_float.from_bytes(memory)
+        self.assertTrue(math.isnan(obj.value))
+
+    def test_c_float_freeze(self):
+        memory = bytearray(pystruct.pack("<f", 9.5))
+        lib = inflater(memory)
+        obj = lib.inflate(c_float, 0)
+
+        obj.freeze()
+        self.assertAlmostEqual(obj.value, 9.5)
+
+        with self.assertRaises(ValueError):
+            obj.value = 1.0
+
+    def test_c_float_dunder(self):
+        memory = pystruct.pack("<f", 3.14)
+        obj = c_float.from_bytes(memory)
+        self.assertAlmostEqual(float(obj), 3.14, places=5)
+
+
 class CStrTest(unittest.TestCase):
     """c_str indexing, iteration, and mutation."""