From d15f67e6005fbc1d506813e0b2e877f7aa057b9d Mon Sep 17 00:00:00 2001
From: Zhiyuan Chen <this@zyc.ai>
Date: Thu, 9 Nov 2023 16:18:19 +0800
Subject: [PATCH] return Self type

---
 chanfig/config.py      | 18 ++++++-------
 chanfig/flat_dict.py   | 58 +++++++++++++++++++++---------------------
 chanfig/nested_dict.py | 12 ++++-----
 3 files changed, 44 insertions(+), 44 deletions(-)

diff --git a/chanfig/config.py b/chanfig/config.py
index c0db0804..d843b4c9 100755
--- a/chanfig/config.py
+++ b/chanfig/config.py
@@ -18,7 +18,7 @@
 from collections.abc import Callable, Iterable
 from contextlib import contextmanager
 from functools import wraps
-from typing import Any
+from typing import Any, Self
 
 from .nested_dict import NestedDict
 from .parser import ConfigParser
@@ -101,7 +101,7 @@ def __init__(self, *args: Any, default_factory: Callable | None = None, **kwargs
             default_factory = Config
         super().__init__(*args, default_factory=default_factory, **kwargs)
 
-    def post(self) -> Config | None:
+    def post(self) -> Self | None:
         r"""
         Post process of `Config`.
 
@@ -138,7 +138,7 @@ def post(self) -> Config | None:
         self.validate()
         return self
 
-    def boot(self) -> Config:
+    def boot(self) -> Self:
         r"""
         Apply `post` recursively.
 
@@ -192,7 +192,7 @@ def parse(
         default_config: str | None = None,
         no_default_config_action: str = "raise",
         boot: bool = True,
-    ) -> Config:
+    ) -> Self:
         r"""
 
         Parse command-line arguments with `ConfigParser`.
@@ -235,7 +235,7 @@ def parse_config(
         default_config: str | None = None,
         no_default_config_action: str = "raise",
         boot: bool = True,
-    ) -> Config:
+    ) -> Self:
         r"""
 
         Parse command-line arguments with `ConfigParser`.
@@ -289,7 +289,7 @@ def add_argument(self, *args: Any, **kwargs: Any) -> None:
             self.setattr("parser", ConfigParser())
         return self.getattr("parser").add_argument(*args, **kwargs)
 
-    def freeze(self, recursive: bool = True) -> Config:
+    def freeze(self, recursive: bool = True) -> Self:
         r"""
         Freeze `Config`.
 
@@ -327,7 +327,7 @@ def freeze(config: Config) -> None:
             freeze(self)
         return self
 
-    def lock(self, recursive: bool = True) -> Config:
+    def lock(self, recursive: bool = True) -> Self:
         r"""
         Alias of [`freeze`][chanfig.Config.freeze].
         """
@@ -357,7 +357,7 @@ def locked(self):
             if not was_frozen:
                 self.defrost()
 
-    def defrost(self, recursive: bool = True) -> Config:
+    def defrost(self, recursive: bool = True) -> Self:
         r"""
         Defrost `Config`.
 
@@ -399,7 +399,7 @@ def defrost(config: Config) -> None:
             defrost(self)
         return self
 
-    def unlock(self, recursive: bool = True) -> Config:
+    def unlock(self, recursive: bool = True) -> Self:
         r"""
         Alias of [`defrost`][chanfig.Config.defrost].
         """
diff --git a/chanfig/flat_dict.py b/chanfig/flat_dict.py
index 20f27de6..8b89810b 100644
--- a/chanfig/flat_dict.py
+++ b/chanfig/flat_dict.py
@@ -25,7 +25,7 @@
 from json import loads as json_loads
 from os import PathLike
 from os.path import splitext
-from typing import IO, Any
+from typing import IO, Any, Self
 from warnings import warn
 
 from yaml import dump as yaml_dump
@@ -524,7 +524,7 @@ def from_dict(cls, obj: Mapping | Sequence) -> Any:  # pylint: disable=R0911
                 return [cls(json) for json in obj]
         raise TypeError(f"Expected Mapping or Sequence, but got {type(obj)}.")
 
-    def sort(self, key: Callable | None = None, reverse: bool = False) -> FlatDict:
+    def sort(self, key: Callable | None = None, reverse: bool = False) -> Self:
         r"""
         Sort `FlatDict`.
 
@@ -553,7 +553,7 @@ def sort(self, key: Callable | None = None, reverse: bool = False) -> FlatDict:
 
     def interpolate(  # pylint: disable=R0912
         self, use_variable: bool = True, interpolators: MutableMapping | None = None
-    ) -> FlatDict:
+    ) -> Self:
         r"""
         Perform Variable interpolation.
 
@@ -667,7 +667,7 @@ def substitute(placeholder, interpolators, value):
         except KeyError as exc:
             raise ValueError(f"{exc} is not found in {interpolators}.") from None
 
-    def merge(self, *args: Any, overwrite: bool = True, **kwargs: Any) -> FlatDict:
+    def merge(self, *args: Any, overwrite: bool = True, **kwargs: Any) -> Self:
         r"""
         Merge `other` into `FlatDict`.
 
@@ -736,13 +736,13 @@ def _merge(this: FlatDict, that: Iterable, overwrite: bool = True) -> Mapping:
                 this.set(key, value)
         return this
 
-    def union(self, *args: Any, **kwargs: Any) -> FlatDict:
+    def union(self, *args: Any, **kwargs: Any) -> Self:
         r"""
         Alias of [`merge`][chanfig.FlatDict.merge].
         """
         return self.merge(*args, **kwargs)
 
-    def merge_from_file(self, file: File, *args: Any, **kwargs: Any) -> FlatDict:
+    def merge_from_file(self, file: File, *args: Any, **kwargs: Any) -> Self:
         r"""
         Merge content of `file` into `FlatDict`.
 
@@ -762,7 +762,7 @@ def merge_from_file(self, file: File, *args: Any, **kwargs: Any) -> FlatDict:
 
         return self.merge(self.load(file, *args, **kwargs))
 
-    def intersect(self, other: Mapping | Iterable | PathStr) -> FlatDict:
+    def intersect(self, other: Mapping | Iterable | PathStr) -> Self:
         r"""
         Intersection of `FlatDict` and `other`.
 
@@ -801,13 +801,13 @@ def intersect(self, other: Mapping | Iterable | PathStr) -> FlatDict:
             raise TypeError(f"`other={other}` should be of type Mapping, Iterable or PathStr, but got {type(other)}.")
         return self.empty(**{key: value for key, value in other if key in self and self[key] == value})  # type: ignore
 
-    def inter(self, other: Mapping | Iterable | PathStr, *args: Any, **kwargs: Any) -> FlatDict:
+    def inter(self, other: Mapping | Iterable | PathStr, *args: Any, **kwargs: Any) -> Self:
         r"""
         Alias of [`intersect`][chanfig.FlatDict.intersect].
         """
         return self.intersect(other, *args, **kwargs)
 
-    def difference(self, other: Mapping | Iterable | PathStr) -> FlatDict:
+    def difference(self, other: Mapping | Iterable | PathStr) -> Self:
         r"""
         Difference between `FlatDict` and `other`.
 
@@ -848,13 +848,13 @@ def difference(self, other: Mapping | Iterable | PathStr) -> FlatDict:
             **{key: value for key, value in other if key not in self or self[key] != value}  # type: ignore
         )
 
-    def diff(self, other: Mapping | Iterable | PathStr, *args: Any, **kwargs: Any) -> FlatDict:
+    def diff(self, other: Mapping | Iterable | PathStr, *args: Any, **kwargs: Any) -> Self:
         r"""
         Alias of [`difference`][chanfig.FlatDict.difference].
         """
         return self.difference(other, *args, **kwargs)
 
-    def to(self, cls: str | TorchDevice | TorchDType) -> FlatDict:  # pragma: no cover
+    def to(self, cls: str | TorchDevice | TorchDType) -> Self:  # pragma: no cover
         r"""
         Convert values of `FlatDict` to target `cls`.
 
@@ -881,7 +881,7 @@ def to(self, cls: str | TorchDevice | TorchDType) -> FlatDict:  # pragma: no cov
 
         raise TypeError(f"to() only support torch.dtype and torch.device, but got {cls}.")
 
-    def cpu(self) -> FlatDict:  # pragma: no cover
+    def cpu(self) -> Self:  # pragma: no cover
         r"""
         Move all tensors to cpu.
 
@@ -897,7 +897,7 @@ def cpu(self) -> FlatDict:  # pragma: no cover
 
         return self.to(TorchDevice("cpu"))
 
-    def gpu(self) -> FlatDict:  # pragma: no cover
+    def gpu(self) -> Self:  # pragma: no cover
         r"""
         Move all tensors to gpu.
 
@@ -919,13 +919,13 @@ def gpu(self) -> FlatDict:  # pragma: no cover
 
         return self.to(TorchDevice("cuda"))
 
-    def cuda(self) -> FlatDict:  # pragma: no cover
+    def cuda(self) -> Self:  # pragma: no cover
         r"""
         Alias of [`gpu`][chanfig.FlatDict.gpu].
         """
         return self.gpu()
 
-    def tpu(self) -> FlatDict:  # pragma: no cover
+    def tpu(self) -> Self:  # pragma: no cover
         r"""
         Move all tensors to tpu.
 
@@ -947,13 +947,13 @@ def tpu(self) -> FlatDict:  # pragma: no cover
 
         return self.to(TorchDevice("xla"))
 
-    def xla(self) -> FlatDict:  # pragma: no cover
+    def xla(self) -> Self:  # pragma: no cover
         r"""
         Alias of [`tpu`][chanfig.FlatDict.tpu].
         """
         return self.tpu()
 
-    def copy(self) -> FlatDict:
+    def copy(self) -> Self:
         r"""
         Create a shallow copy of `FlatDict`.
 
@@ -975,7 +975,7 @@ def copy(self) -> FlatDict:
 
         return copy(self)
 
-    def __deepcopy__(self, memo: Mapping | None = None) -> FlatDict:
+    def __deepcopy__(self, memo: Mapping | None = None) -> Self:
         # pylint: disable=C0103
 
         if memo is not None and id(self) in memo:
@@ -989,7 +989,7 @@ def __deepcopy__(self, memo: Mapping | None = None) -> FlatDict:
                 ret[k] = deepcopy(v)
         return ret
 
-    def deepcopy(self, memo: Mapping | None = None) -> FlatDict:  # pylint: disable=W0613
+    def deepcopy(self, memo: Mapping | None = None) -> Self:  # pylint: disable=W0613
         r"""
         Create a deep copy of `FlatDict`.
 
@@ -1017,7 +1017,7 @@ def deepcopy(self, memo: Mapping | None = None) -> FlatDict:  # pylint: disable=
 
         return deepcopy(self)
 
-    def clone(self, memo: Mapping | None = None) -> FlatDict:
+    def clone(self, memo: Mapping | None = None) -> Self:
         r"""
         Alias of [`deepcopy`][chanfig.FlatDict.deepcopy].
         """
@@ -1067,7 +1067,7 @@ def dump(self, file: File, method: str | None = None, *args: Any, **kwargs: Any)
     @classmethod
     def load(  # pylint: disable=W1113
         cls, file: File, method: str | None = None, *args: Any, **kwargs: Any
-    ) -> FlatDict:
+    ) -> Self:
         """
         Load `FlatDict` from file.
 
@@ -1122,7 +1122,7 @@ def json(self, file: File, *args: Any, **kwargs: Any) -> None:
             fp.write(self.jsons(*args, **kwargs))
 
     @classmethod
-    def from_json(cls, file: File, *args: Any, **kwargs: Any) -> FlatDict:
+    def from_json(cls, file: File, *args: Any, **kwargs: Any) -> Self:
         r"""
         Construct `FlatDict` from json file.
 
@@ -1161,7 +1161,7 @@ def jsons(self, *args: Any, **kwargs: Any) -> str:
         return json_dumps(self.dict(), *args, **kwargs)
 
     @classmethod
-    def from_jsons(cls, string: str, *args: Any, **kwargs: Any) -> FlatDict:
+    def from_jsons(cls, string: str, *args: Any, **kwargs: Any) -> Self:
         r"""
         Construct `FlatDict` from json string.
 
@@ -1195,7 +1195,7 @@ def yaml(self, file: File, *args: Any, **kwargs: Any) -> None:
             self.yamls(fp, *args, **kwargs)
 
     @classmethod
-    def from_yaml(cls, file: File, *args: Any, **kwargs: Any) -> FlatDict:
+    def from_yaml(cls, file: File, *args: Any, **kwargs: Any) -> Self:
         r"""
         Construct `FlatDict` from yaml file.
 
@@ -1233,7 +1233,7 @@ def yamls(self, *args: Any, **kwargs: Any) -> str:
         return yaml_dump(self.dict(), *args, **kwargs)  # type: ignore
 
     @classmethod
-    def from_yamls(cls, string: str, *args: Any, **kwargs: Any) -> FlatDict:
+    def from_yamls(cls, string: str, *args: Any, **kwargs: Any) -> Self:
         r"""
         Construct `FlatDict` from yaml string.
 
@@ -1304,7 +1304,7 @@ def open(file: File, *args: Any, encoding: str = "utf-8", **kwargs: Any) -> Gene
             raise TypeError(f"expected str, bytes, os.PathLike, IO or IOBase, not {type(file).__name__}")
 
     @classmethod
-    def empty(cls, *args: Any, **kwargs: Any) -> FlatDict:
+    def empty(cls, *args: Any, **kwargs: Any) -> Self:
         r"""
         Initialise an empty `FlatDict`.
 
@@ -1330,7 +1330,7 @@ def empty(cls, *args: Any, **kwargs: Any) -> FlatDict:
         empty.merge(*args, **kwargs)  # pylint: disable=W0212
         return empty
 
-    def empty_like(self, *args: Any, **kwargs: Any) -> FlatDict:
+    def empty_like(self, *args: Any, **kwargs: Any) -> Self:
         r"""
         Initialise an empty copy of `FlatDict`.
 
@@ -1392,7 +1392,7 @@ def all_items(self) -> Generator:
         """
         yield from self.items()
 
-    def dropnull(self) -> FlatDict:
+    def dropnull(self) -> Self:
         r"""
         Drop key-value pairs with `Null` value.
 
@@ -1415,7 +1415,7 @@ def dropnull(self) -> FlatDict:
 
         return self.empty({k: v for k, v in self.all_items() if v is not Null})
 
-    def dropna(self) -> FlatDict:
+    def dropna(self) -> Self:
         r"""
         Alias of [`dropnull`][chanfig.FlatDict.dropnull].
         """
diff --git a/chanfig/nested_dict.py b/chanfig/nested_dict.py
index 862e9601..38afa3f9 100644
--- a/chanfig/nested_dict.py
+++ b/chanfig/nested_dict.py
@@ -20,7 +20,7 @@
 from functools import wraps
 from inspect import ismethod
 from os import PathLike
-from typing import Any
+from typing import Any, Self
 
 try:
     from functools import cached_property  # pylint: disable=C0412
@@ -240,7 +240,7 @@ def all_items(self, prefix=Null):
 
         return all_items(self)
 
-    def apply(self, func: Callable, *args: Any, **kwargs: Any) -> NestedDict:
+    def apply(self, func: Callable, *args: Any, **kwargs: Any) -> Self:
         r"""
         Recursively apply a function to `NestedDict` and its children.
 
@@ -269,7 +269,7 @@ def apply(self, func: Callable, *args: Any, **kwargs: Any) -> NestedDict:
 
         return apply(self, func, *args, **kwargs)
 
-    def apply_(self, func: Callable, *args: Any, **kwargs: Any) -> NestedDict:
+    def apply_(self, func: Callable, *args: Any, **kwargs: Any) -> Self:
         r"""
         Recursively apply a function to `NestedDict` and its children.
 
@@ -655,7 +655,7 @@ def validate(self) -> None:
 
         self.apply_(self._validate)
 
-    def sort(self, key: Callable | None = None, reverse: bool = False, recursive: bool = True) -> NestedDict:
+    def sort(self, key: Callable | None = None, reverse: bool = False, recursive: bool = True) -> Self:
         r"""
         Sort `NestedDict`.
 
@@ -715,7 +715,7 @@ def _merge(this: FlatDict, that: Iterable, overwrite: bool = True) -> Mapping:
 
     def intersect(  # pylint: disable=W0221
         self, other: Mapping | Iterable | PathStr, recursive: bool = True
-    ) -> NestedDict:
+    ) -> Self:
         r"""
         Intersection of `NestedDict` and `other`.
 
@@ -763,7 +763,7 @@ def _intersect(this: NestedDict, that: Iterable, recursive: bool = True) -> Mapp
 
     def difference(  # pylint: disable=W0221, C0103
         self, other: Mapping | Iterable | PathStr, recursive: bool = True
-    ) -> NestedDict:
+    ) -> Self:
         r"""
         Difference between `NestedDict` and `other`.