Patch in enum deepcopy on Python 3.10 (#312)

Author: stefanv

pyproject.toml

@@ -23,7 +23,6 @@ classifiers = [
   "Programming Language :: Python :: 3 :: Only",
 ]
 dependencies = [
-  "click>=8,<=8.2; python_version == '3.10'",  # cannot deepcopy cmd params (specifically, Sentinel.UNSET) on 3.10
   "click>=8,!=8.3.0,<8.4",
   "tomli; python_version < '3.11'",
   "colorama; platform_system == 'Windows'",

spin/cmds/util.py

@@ -3,6 +3,7 @@
 )
 
 import copy
+import enum
 import os
 import shlex
 import shutil
@@ -159,6 +160,14 @@ def build(*, parent_callback, extra=None, **kwargs):
     """
     my_cmd = copy.copy(cmd)
 
+    # This patch is to work around an enum deepcopy bug in Python 3.10.
+    if not hasattr(enum.Enum, "__deepcopy__"):
+
+        def __deepcopy__(self, memo):
+            return self
+
+        enum.Enum.__deepcopy__ = __deepcopy__  # type: ignore[method-assign]
+
     # This is necessary to ensure that added options do not leak
     # to the original command
     my_cmd.params = copy.deepcopy(cmd.params)