tests: add some DCPacker unit tests (for #751)

tests/dcparser/test_dcpacker.py

@@ -0,0 +1,36 @@
+import pytest
+
+direct = pytest.importorskip("panda3d.direct")
+
+
+def test_pack_int8():
+    for num in range(-128, 128):
+        packer = direct.DCPacker()
+        packer.raw_pack_int8(num)
+        packer.set_unpack_data(packer.get_bytes())
+        assert packer.raw_unpack_int8() == num
+
+
+def test_pack_uint8():
+    for num in range(256):
+        packer = direct.DCPacker()
+        packer.raw_pack_uint8(num)
+        packer.set_unpack_data(packer.get_bytes())
+        assert packer.raw_unpack_uint8() == num
+
+
+def test_pack_int64():
+    for num in (0, -1, 0x7fffffff, -0x80000000, 0x7fffffffffffffff, 0x7ffffffffffffffe, -0x8000000000000000, -0x7fffffffffffffff):
+        packer = direct.DCPacker()
+        packer.raw_pack_int64(num)
+        packer.set_unpack_data(packer.get_bytes())
+        assert packer.raw_unpack_int64() == num
+
+
+def test_pack_uint64():
+    for num in (0, 1, 0x7fffffff, 0xffffffff, 0x7fffffffffffffff, 0xfffffffffffffffe, 0xffffffffffffffff):
+        packer = direct.DCPacker()
+        packer.raw_pack_uint64(num)
+        packer.set_unpack_data(packer.get_bytes())
+        assert packer.raw_unpack_uint64() == num
+