add global SENTINEL object

gallery_dl/cache.py

@@ -189,8 +189,8 @@ def clear():
 
 
 def _path():
-    path = config.get(("cache",), "file", -1)
-    if path != -1:
+    path = config.get(("cache",), "file", util.SENTINEL)
+    if path is not util.SENTINEL:
         return util.expand_path(path)
 
     if util.WINDOWS:

gallery_dl/config.py

@@ -139,20 +139,19 @@ def unset(path, key, *, conf=_config):
 
 class apply():
     """Context Manager: apply a collection of key-value pairs"""
-    _sentinel = object()
 
     def __init__(self, kvlist):
         self.original = []
         self.kvlist = kvlist
 
     def __enter__(self):
         for path, key, value in self.kvlist:
-            self.original.append((path, key, get(path, key, self._sentinel)))
+            self.original.append((path, key, get(path, key, util.SENTINEL)))
             set(path, key, value)
 
     def __exit__(self, etype, value, traceback):
         for path, key, value in self.original:
-            if value is self._sentinel:
+            if value is util.SENTINEL:
                 unset(path, key)
             else:
                 set(path, key, value)

gallery_dl/extractor/common.py

@@ -481,7 +481,7 @@ class SharedConfigMixin():
     """Enable sharing of config settings based on 'basecategory'"""
     basecategory = ""
 
-    def config(self, key, default=None, *, sentinel=object()):
+    def config(self, key, default=None, *, sentinel=util.SENTINEL):
         value = Extractor.config(self, key, sentinel)
         return value if value is not sentinel else config.interpolate(
             ("extractor", self.basecategory, self.subcategory), key, default)

gallery_dl/extractor/mastodon.py

@@ -27,11 +27,9 @@ def __init__(self, match):
         Extractor.__init__(self, match)
         self.api = MastodonAPI(self)
 
-    def config(self, key, default=None, *, sentinel=object()):
+    def config(self, key, default=None, *, sentinel=util.SENTINEL):
         value = Extractor.config(self, key, sentinel)
-        if value is not sentinel:
-            return value
-        return config.interpolate(
+        return value if value is not sentinel else config.interpolate(
             ("extractor", "mastodon", self.instance, self.subcategory),
             key, default,
         )

gallery_dl/util.py

@@ -271,6 +271,7 @@ def __str__():
 
 NONE = UniversalNone()
 WINDOWS = (os.name == "nt")
+SENTINEL = object()
 
 
 def build_predicate(predicates):