Use Self for more accurate typing (#201)

* Use Self for more accurate typing

* chore: Remove pyright for now

pyproject.toml

@@ -27,6 +27,7 @@ authors = [
 ]
 dependencies = [
     "importlib_resources>=5.10; python_version <= '3.11'",
+    "typing_extensions>=4.0; python_version <= '3.11'",
     "iso3166",
     "pycountry",
 ]

schwifty/bban.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 from typing import Any
-from typing import cast
 
 from schwifty import common
 from schwifty import exceptions
@@ -11,6 +10,11 @@
 from schwifty.domain import Component
 
 
+try:
+    from typing import Self
+except ImportError:
+    from typing_extensions import Self
+
 EMPTY_RANGE = (0, 0)
 
 
@@ -61,8 +65,8 @@ class BBAN(common.Base):
     .. versionadded:: 2024.01.1
     """
 
-    def __new__(cls: type[BBAN], country_code: str, value: str, **kwargs: Any) -> BBAN:
-        return cast(BBAN, super().__new__(cls, value, **kwargs))
+    def __new__(cls: type[Self], country_code: str, value: str, **kwargs: Any) -> Self:
+        return super().__new__(cls, value, **kwargs)
 
     def __init__(self, country_code: str, value: str) -> None:
         self.country_code = country_code

schwifty/common.py

@@ -5,12 +5,18 @@
 from typing import Any
 
 
+try:
+    from typing import Self
+except ImportError:
+    from typing_extensions import Self
+
+
 _clean_regex = re.compile(r"\s+")
 
 
 @total_ordering
 class Base(str):
-    def __new__(cls: type[Base], value: str, **kwargs: Any) -> Base:
+    def __new__(cls: type[Self], value: str, **kwargs: Any) -> Self:
         return super().__new__(cls, clean(value))
 
     def __repr__(self) -> str: