fix config/cache dir compatibility issues, fixes #7445 (#7448)

fix config dir compatibility issue, fixes #7445

- add tests
- make sure the result of get_cache_dir matches pre and post #7300 where desired
- harmonize implementation of config_dir_compat and cache_dir_compat tests

Co-authored-by: nain <126972030+F49FF806@users.noreply.github.com>

src/borg/helpers/fs.py

@@ -106,7 +106,7 @@ def get_cache_dir(*, legacy=False):
         cache_dir = os.environ.get("BORG_CACHE_DIR", os.path.join(cache_home, "borg"))
     else:
         cache_dir = os.environ.get(
-            "BORG_CACHE_DIR", join_base_dir(".cache", legacy=legacy) or platformdirs.user_cache_dir("borg")
+            "BORG_CACHE_DIR", join_base_dir(".cache", "borg", legacy=legacy) or platformdirs.user_cache_dir("borg")
         )
 
     # Create path if it doesn't exist yet
@@ -143,7 +143,7 @@ def get_config_dir(*, legacy=False):
         config_dir = os.environ.get("BORG_CONFIG_DIR", os.path.join(config_home, "borg"))
     else:
         config_dir = os.environ.get(
-            "BORG_CONFIG_DIR", join_base_dir(".config", legacy=legacy) or platformdirs.user_config_dir("borg")
+            "BORG_CONFIG_DIR", join_base_dir(".config", "borg", legacy=legacy) or platformdirs.user_config_dir("borg")
         )
 
     # Create path if it doesn't exist yet

src/borg/testsuite/helpers.py

@@ -635,19 +635,20 @@ def test_get_config_dir(monkeypatch):
 
 def test_get_config_dir_compat(monkeypatch):
     """test that it works the same for legacy and for non-legacy implementation"""
+    monkeypatch.delenv("BORG_CONFIG_DIR", raising=False)
     monkeypatch.delenv("BORG_BASE_DIR", raising=False)
+    monkeypatch.delenv("XDG_CONFIG_HOME", raising=False)
     if not is_darwin and not is_win32:
-        monkeypatch.delenv("BORG_CONFIG_DIR", raising=False)
-        monkeypatch.delenv("XDG_CONFIG_HOME", raising=False)
         # fails on macOS: assert '/Users/tw/Library/Application Support/borg' == '/Users/tw/.config/borg'
         # fails on win32 MSYS2 (but we do not need legacy compat there).
         assert get_config_dir(legacy=False) == get_config_dir(legacy=True)
-    if not is_darwin and not is_win32:
-        monkeypatch.setenv("XDG_CONFIG_HOME", "/var/tmp/.config1")
-        # fails on macOS: assert '/Users/tw/Library/Application Support/borg' == '/var/tmp/.config1/borg'
+        monkeypatch.setenv("XDG_CONFIG_HOME", "/var/tmp/xdg.config.d")
+        # fails on macOS: assert '/Users/tw/Library/Application Support/borg' == '/var/tmp/xdg.config.d'
         # fails on win32 MSYS2 (but we do not need legacy compat there).
         assert get_config_dir(legacy=False) == get_config_dir(legacy=True)
-    monkeypatch.setenv("BORG_CONFIG_DIR", "/var/tmp/.config2")
+    monkeypatch.setenv("BORG_BASE_DIR", "/var/tmp/base")
+    assert get_config_dir(legacy=False) == get_config_dir(legacy=True)
+    monkeypatch.setenv("BORG_CONFIG_DIR", "/var/tmp/borg.config.d")
     assert get_config_dir(legacy=False) == get_config_dir(legacy=True)
 
 
@@ -675,6 +676,25 @@ def test_get_cache_dir(monkeypatch):
         assert get_cache_dir() == "/var/tmp"
 
 
+def test_get_cache_dir_compat(monkeypatch):
+    """test that it works the same for legacy and for non-legacy implementation"""
+    monkeypatch.delenv("BORG_CACHE_DIR", raising=False)
+    monkeypatch.delenv("BORG_BASE_DIR", raising=False)
+    monkeypatch.delenv("XDG_CACHE_HOME", raising=False)
+    if not is_darwin and not is_win32:
+        # fails on macOS: assert '/Users/tw/Library/Caches/borg' == '/Users/tw/.cache/borg'
+        # fails on win32 MSYS2 (but we do not need legacy compat there).
+        assert get_cache_dir(legacy=False) == get_cache_dir(legacy=True)
+        # fails on macOS: assert '/Users/tw/Library/Caches/borg' == '/var/tmp/xdg.cache.d'
+        # fails on win32 MSYS2 (but we do not need legacy compat there).
+        monkeypatch.setenv("XDG_CACHE_HOME", "/var/tmp/xdg.cache.d")
+        assert get_cache_dir(legacy=False) == get_cache_dir(legacy=True)
+    monkeypatch.setenv("BORG_BASE_DIR", "/var/tmp/base")
+    assert get_cache_dir(legacy=False) == get_cache_dir(legacy=True)
+    monkeypatch.setenv("BORG_CACHE_DIR", "/var/tmp/borg.cache.d")
+    assert get_cache_dir(legacy=False) == get_cache_dir(legacy=True)
+
+
 def test_get_keys_dir(monkeypatch):
     """test that get_keys_dir respects environment"""
     monkeypatch.delenv("BORG_BASE_DIR", raising=False)