core: migrate from deprecated appdirs to platformdirs

resolves #377

doc/SETUP.org

@@ -54,7 +54,7 @@ I understand that people who'd like to use this may not be super familiar with P
 - when you are using ~pip install~, [[https://stackoverflow.com/a/42989020/706389][always pass]] =--user=, and *never install third party packages with sudo* (unless you know what you are doing)
 - throughout the guide I'm assuming the user config directory is =~/.config=, but it's *different on Mac/Windows*.
 
-  See [[https://github.com/ActiveState/appdirs/blob/3fe6a83776843a46f20c2e5587afcffe05e03b39/appdirs.py#L187-L190][this]] if you're not sure what's your user config dir.
+  See [[https://github.com/tox-dev/platformdirs?tab=readme-ov-file#example-output][this]] if you're not sure what's your user config dir.
 
 * Install main HPI package
 This is a *required step*

pyproject.toml

@@ -7,7 +7,7 @@ name = "HPI"
 dependencies = [
     "pytz"                   , # even though it's not needed by the core, it's so common anyway...
     "typing-extensions"      , # one of the most common pypi packages, ok to depend for core
-    "appdirs"                , # very common, and makes it portable
+    "platformdirs"           , # very common, and makes it portable
     "more-itertools"         , # it's just too useful and very common anyway
     "decorator"              , # less pain in writing correct decorators. very mature and stable, so worth keeping in core
     "click>=8.1"             , # for the CLI, printing colors, decorator-based - may allow extensions to CLI

src/my/core/cachew.py

@@ -1,9 +1,5 @@
 from __future__ import annotations
 
-from .internal import assert_subpackage
-
-assert_subpackage(__name__)
-
 import logging
 import sys
 from collections.abc import Iterator
@@ -19,7 +15,7 @@
     overload,
 )
 
-import appdirs  # type: ignore[import-untyped]
+import platformdirs
 
 from . import warnings
 
@@ -52,8 +48,8 @@ def disabled_cachew() -> Iterator[None]:
         yield
 
 
-def _appdirs_cache_dir() -> Path:
-    cd = Path(appdirs.user_cache_dir('my'))
+def _hpi_cache_dir() -> Path:
+    cd = Path(platformdirs.user_cache_dir('my'))
     cd.mkdir(exist_ok=True, parents=True)
     return cd
 

src/my/core/core_config.py

@@ -42,7 +42,7 @@ class config:
     '''
     Base directory for cachew.
     - if None             , means cache is disabled
-    - if '' (empty string), use user cache dir (see https://github.com/ActiveState/appdirs for more info). This is the default.
+    - if '' (empty string), use user cache dir (see https://github.com/tox-dev/platformdirs?tab=readme-ov-file#example-output for more info). This is the default.
     - otherwise           , use the specified directory as base cache directory
 
     NOTE: you shouldn't use this attribute in HPI modules directly, use Config.get_cache_dir()/cachew.cache_dir() instead
@@ -73,9 +73,9 @@ def get_cache_dir(self) -> Path | None:
         if cdir is None:
             return None
         if cdir == _HPI_CACHE_DIR_DEFAULT:
-            from .cachew import _appdirs_cache_dir
+            from .cachew import _hpi_cache_dir
 
-            return _appdirs_cache_dir()
+            return _hpi_cache_dir()
         else:
             return Path(cdir).expanduser()
 

src/my/core/preinit.py

@@ -7,13 +7,13 @@
 def get_mycfg_dir() -> Path:
     import os
 
-    import appdirs  # type: ignore[import-untyped]
+    import platformdirs
 
     # not sure if that's necessary, i.e. could rely on PYTHONPATH instead
     # on the other hand, by using MY_CONFIG we are guaranteed to load it from the desired path?
     mvar = os.environ.get('MY_CONFIG')
     if mvar is not None:
         mycfg_dir = Path(mvar)
     else:
-        mycfg_dir = Path(appdirs.user_config_dir('my'))
+        mycfg_dir = Path(platformdirs.user_config_dir('my'))
     return mycfg_dir