There are a few small adjustments we can make to pathlib path initialization and joining that improve performance:

1. Ignore empty strings given to the initializer, which saves a pathmod.join() call
2. Store joined string in self._raw_paths, which makes subsequent joining faster
3. Handle empty paths without calling _parse_path()
4. Check for the common case (len(self._raw_paths) == 1) first, and replace a length check with a truth check in the subsequent elif:
5. Remove some unneeded local variables.

Linked PRs

• GH-113373: Speed up pathlib parsing by avoiding some attribute lookup misses #113375
• GH-113373: Speed up pathlib parsing using __init_subclass__() #113409