Change user_log_dir to point to user_state_dir on Linux per the XDG s…

…pec (#108)

Fixes #106

CHANGES.rst

@@ -1,6 +1,11 @@
 platformdirs Changelog
 ======================
 
+platformdirs 2.6.0 (2022-12-06)
+-------------------------------
+- **BREAKING** Correct the log directory on Linux/Unix from
+  XDG_CACHE_HOME to XDG_STATE_HOME per the XDG spec
+
 platformdirs 2.5.4 (2022-11-12)
 -------------------------------
 - Fix licesing metadata

src/platformdirs/unix.py

@@ -107,9 +107,9 @@ def user_state_dir(self) -> str:
     @property
     def user_log_dir(self) -> str:
         """
-        :return: log directory tied to the user, same as `user_data_dir` if not opinionated else ``log`` in it
+        :return: log directory tied to the user, same as `user_state_dir` if not opinionated else ``log`` in it
         """
-        path = self.user_cache_dir
+        path = self.user_state_dir
         if self.opinion:
             path = os.path.join(path, "log")
         return path

tests/test_comp_with_appdirs.py

@@ -62,6 +62,12 @@ def test_compatibility(params: dict[str, Any], func: str) -> None:
         }
         if func in msg:  # pragma: no cover
             pytest.skip(f"`appdirs.{func}` {msg[func]} on macOS")  # pragma: no cover
+    if sys.platform == "linux":
+        msg = {  # pragma: no cover
+            "user_log_dir": "Uses XDG_STATE_DIR instead of appdirs.user_data_dir per the XDG spec",
+        }
+        if func in msg:  # pragma: no cover
+            pytest.skip(f"`appdirs.{func}` {msg[func]} on Linux")  # pragma: no cover
 
     new = getattr(platformdirs, func)(*params)
     old = getattr(appdirs, func)(*params)

tests/test_unix.py

@@ -59,7 +59,7 @@ def _func_to_path(func: str) -> XDGVariable | None:
         "site_config_dir": XDGVariable("XDG_CONFIG_DIRS", "/etc/xdg"),
         "user_cache_dir": XDGVariable("XDG_CACHE_HOME", "~/.cache"),
         "user_state_dir": XDGVariable("XDG_STATE_HOME", "~/.local/state"),
-        "user_log_dir": XDGVariable("XDG_CACHE_HOME", "~/.cache"),
+        "user_log_dir": XDGVariable("XDG_STATE_HOME", "~/.local/state"),
         "user_runtime_dir": XDGVariable("XDG_RUNTIME_DIR", "/run/user/1234"),
     }
     return mapping.get(func)