Test fixes from PR

Author: rambleraptor

pyiceberg/catalog/rest/__init__.py

@@ -231,10 +231,6 @@ def __init__(self, name: str, **properties: str):
         self.uri = properties[URI]
         self._fetch_config()
         self._session = self._create_session()
-        separator_from_properties = self.properties.get(NAMESPACE_SEPARATOR_PROPERTY, DEFAULT_NAMESPACE_SEPARATOR)
-        if not separator_from_properties:
-            raise ValueError("Namespace separator cannot be an empty string")
-        self._namespace_separator = unquote(separator_from_properties)
 
     def _create_session(self) -> Session:
         """Create a request session with provided catalog configuration."""
@@ -389,6 +385,11 @@ def _fetch_config(self) -> None:
         # Update URI based on overrides
         self.uri = config[URI]
 
+        separator_from_properties = self.properties.get(NAMESPACE_SEPARATOR_PROPERTY, DEFAULT_NAMESPACE_SEPARATOR)
+        if not separator_from_properties:
+            raise ValueError("Namespace separator cannot be an empty string")
+        self._namespace_separator = unquote(separator_from_properties)
+
     def _identifier_to_validated_tuple(self, identifier: str | Identifier) -> Identifier:
         identifier_tuple = self.identifier_to_tuple(identifier)
         if len(identifier_tuple) <= 1:
@@ -405,6 +406,7 @@ def _split_identifier_for_path(
             }
         identifier_tuple = self._identifier_to_validated_tuple(identifier)
 
+        # Use quote to ensure that '/' aren't treated as path separators.
         return {
             "namespace": self._encode_namespace_path(identifier_tuple[:-1]),
             kind.value: quote(identifier_tuple[-1], safe=""),