bump version, add test

setup.py

@@ -5,7 +5,7 @@
 
 setuptools.setup(
     name="permacache",
-    version="3.8.0",
+    version="3.9.0",
     author="Kavi Gupta",
     author_email="[email protected]",
     description="Permanant cache.",

tests/test_module/c.py

@@ -0,0 +1,34 @@
+from dataclasses import dataclass
+
+import attr
+
+from permacache import migrated_attrs
+
+
+@attr.s
+class A:
+    x = attr.ib()
+    y = attr.ib()
+    z = attr.ib()
+
+
+@attr.dataclass
+class B:
+    x: int
+    y: str
+    z: float
+
+
+@dataclass
+class C:
+    x: int
+    y: str
+    z: float
+
+
+@dataclass
+@migrated_attrs
+class D:
+    x: int
+    y: str
+    z: float