feat: add local deprecation descriptor (in reserve; not used) (#28695)

* feat: add local deprecation descriptor (in reserve; not used)

frappe/deprecation_dumpster.py

@@ -20,6 +20,7 @@ import inspect
 import os
 import re
 import sys
+import typing
 import warnings
 from importlib.metadata import version
 
@@ -200,6 +201,44 @@ def deprecation_warning(marked: str, graduation: str, msg: str):
 
 
 ### Party starts here
+
+if typing.TYPE_CHECKING:
+	from werkzeug.local import Local
+
+
+def get_local_with_deprecations() -> "Local":
+	from werkzeug.local import Local
+
+	class DeprecatedLocalAttribute:
+		def __init__(self, name, warning):
+			self.name = name
+			self.warning = warning
+
+		def __get__(self, obj, type=None):
+			self.warning()
+			return obj.__getattr__(self.name)
+
+		def __set__(self, obj, value):
+			return obj.__setattr__(self.name, value)
+
+		def __delete__(self, obj):
+			return obj.__delattr__(self.name)
+
+	class LocalWithDeprecations(Local):
+		"""Can deprecate local attributes."""
+
+		# sites_path = DeprecatedLocalAttribute(
+		# 	"sites_path",
+		# 	lambda: deprecation_warning(
+		# 		"2024-12-06",
+		# 		"v17",
+		# 		"'local.sites_path' will be deprecated: use 'frappe.bench.sites.path instead'",
+		# 	),
+		# )
+
+	return LocalWithDeprecations()
+
+
 def _old_deprecated(func):
 	return deprecated(
 		"frappe.deprecations.deprecated",