fix: ensure enums are hashable

proto/enums.py

@@ -112,6 +112,9 @@ def _comparable(self, other):
         # Avoid 'isinstance' to prevent other IntEnums from matching
         return type(other) in (type(self), int)
 
+    def __hash__(self):
+        return hash(self.value)
+
     def __eq__(self, other):
         if not self._comparable(other):
             return NotImplemented

tests/test_enum_total_ordering.py

@@ -85,3 +85,9 @@ def test_total_ordering_w_int(int_val):
         assert to_compare <= int_val
         assert not to_compare > int_val
         assert to_compare >= int_val
+
+
+def test_hashing():
+    to_hash = enums_test.OneEnum.SOME_VALUE
+
+    {to_hash: "testing"}  # no raise