Fix tests on Python 3

Author: YannickJadoul

tests/test_pytypes.py

@@ -109,12 +109,14 @@ def __repr__(self):
     assert s1 == s2
 
     malformed_utf8 = b"\x80"
-    with pytest.raises(UnicodeDecodeError) as excinfo:
-        assert m.str_from_object(malformed_utf8)
-    assert 'invalid start byte' in str(excinfo.value)
-    with pytest.raises(UnicodeDecodeError) as excinfo:
-        assert m.str_from_handle(malformed_utf8)
-    assert 'invalid start byte' in str(excinfo.value)
+    if sys.version_info.major < 3:
+        with pytest.raises(UnicodeDecodeError):
+            assert m.str_from_object(malformed_utf8)
+        with pytest.raises(UnicodeDecodeError):
+            assert m.str_from_handle(malformed_utf8)
+    else:
+        assert m.str_from_object(malformed_utf8) == "b'\\x80'"
+        assert m.str_from_handle(malformed_utf8) == "b'\\x80'"
 
 
 def test_bytes(doc):