Use platformdirs instead of appdirs (#2142)

Author: gaborbernat

docs/changelog.rst

@@ -128,7 +128,7 @@ Features - 20.2.0
 ~~~~~~~~~~~~~~~~~
 - Optionally skip VCS ignore directive for entire virtualenv directory, using option :option:`no-vcs-ignore`, by default ``False``. (`#2003 <https://github.com/pypa/virtualenv/issues/2003>`_)
 - Add ``--read-only-app-data`` option to allow for creation based on an existing
-  app data cache which is non-writable.  This may be useful (for example) to
+  app data cache which is non-writable. This may be useful (for example) to
   produce a docker image where the app-data is pre-populated.
 
   .. code-block:: dockerfile

docs/changelog/2093.feature.rst

@@ -0,0 +1 @@
+Plugins now use 'selectable' entry points - by :user:`jaraco`.

docs/changelog/2093.misc.rst

@@ -0,0 +1 @@
+Use the better maintained ``platformdirs`` instead of ``appdirs`` - by :user:`gaborbernat`.

docs/changelog/2142.feature.rst

@@ -39,10 +39,10 @@ project_urls =
 [options]
 packages = find:
 install_requires =
-    appdirs>=1.4.3,<2
     backports.entry_points_selectable>=1.0.4
     distlib>=0.3.1,<1
     filelock>=3.0.0,<4
+    platformdirs>=2,<3
     six>=1.9.0,<2   # keep it >=1.9.0 as it may cause problems on LTS platforms
     importlib-metadata>=0.12;python_version<"3.8"
     importlib-resources>=1.0;python_version<"3.7"

setup.cfg

@@ -6,7 +6,7 @@
 import logging
 import os
 
-from appdirs import user_data_dir
+from platformdirs import user_data_dir
 
 from .na import AppDataDisabled
 from .read_only import ReadOnlyAppData

src/virtualenv/app_data/__init__.py

@@ -3,7 +3,7 @@
 import logging
 import os
 
-from appdirs import user_config_dir
+from platformdirs import user_config_dir
 
 from virtualenv.info import PY3
 from virtualenv.util import ConfigParser