[pre-commit] Add "fix-future-annotations" & "pyupgrade" hooks

Now that the next major version of Python finally seems to land with PEP 649 implemented, it seems safe to use `from __future__ import annotations` everywhere we use non-builtin type hints :-)

And thanks to the "flake8 type-checking" rules (re-implemented in Ruff), we can make sure we're still using "if TYPE_CHECKING:" for type-only imports 👌

Author: olivierphi

.pre-commit-config.yaml

@@ -1,21 +1,42 @@
 # See https://pre-commit.com for more information
 # See https://pre-commit.com/hooks.html for more hooks
 repos:
+  
+  # -------------- MyPy: type checking
+  # Although MyPy has limited abilities in a pre-commit context, as it can only 
+  # type-check each file in isolation, it can still catch errors.
   - repo: https://github.com/pre-commit/mirrors-mypy
     rev: v1.11.2
     hooks:
       - id: mypy
-        additional_dependencies: [types-requests==2.31.0.2]
+        additional_dependencies: [ types-requests==2.31.0.2 ]
         exclude: "^scripts/load_testing/.*\\.py$"
+  
+  # -------------- Ruff: linter & "à la Black" formatter 
   - repo: https://github.com/charliermarsh/ruff-pre-commit
     rev: v0.6.3
     hooks:
       # Run the formatter.
       - id: ruff-format
       # Run the linter.
       - id: ruff
-        args: ["--fix"] 
+        args: [ "--fix" ]
         exclude: "^src/project/settings/.*\\.py$"
+  
+  # -------------- pyupgrade: make sure we're using the latest Python features
+  - repo: https://github.com/asottile/pyupgrade
+    rev: v3.19.0
+    hooks:
+      - id: pyupgrade
+        args: [ "--py311-plus" ]
+  
+  # -------------- fix-future-annotations: upgrade the typing annotations syntax to PEP 585 and PEP 604.
+  - repo: https://github.com/frostming/fix-future-annotations
+    rev: 0.5.0  # a released version tag
+    hooks:
+      - id: fix-future-annotations
+  
+  # -------------- validate-pyproject: does what it says on the tin ^_^
   - repo: https://github.com/abravalheri/validate-pyproject
     rev: v0.19
     hooks:

Makefile

@@ -2,7 +2,9 @@ PYTHON_BINS ?= ./.venv/bin
 PYTHON ?= ${PYTHON_BINS}/python
 DJANGO_SETTINGS_MODULE ?= project.settings.development
 SUB_MAKE = ${MAKE} --no-print-directory
+UV_PYTHON ?= ${PYTHON}
 UV ?= bin/uv
+UVX ?= bin/uvx
 
 .DEFAULT_GOAL := help
 
@@ -90,7 +92,7 @@ test: ## Launch the pytest tests suite
 		${PYTHON_BINS}/pytest ${pytest_opts}
 
 .PHONY: code-quality/all
-code-quality/all: code-quality/ruff_check code-quality/ruff_lint code-quality/mypy  ## Run all our code quality tools
+code-quality/all: code-quality/ruff_check code-quality/ruff_lint code-quality/mypy code-quality/fix-future-annotations ## Run all our code quality tools
 
 .PHONY: code-quality/ruff_check
 code-quality/ruff_check: ruff_opts ?=
@@ -110,6 +112,13 @@ code-quality/mypy: ## Python's equivalent of TypeScript
 # @link https://mypy.readthedocs.io/en/stable/
 	@${PYTHON_BINS}/mypy src/ ${mypy_opts}
 
+.PHONY: code-quality/fix-future-annotations
+code-quality/fix-future-annotations: fix_future_annotations_opts ?=
+code-quality/fix-future-annotations: ## Make sure we're using PEP 585 and PEP 604
+# @link https://github.com/frostming/fix-future-annotations
+	@UV_PYTHON=${UV_PYTHON} \
+		${UVX} fix-future-annotations ${fix_future_annotations_opts} src/ 
+
 # Here starts the frontend stuff
 
 .PHONY: frontend/install

pyproject.toml

@@ -87,11 +87,12 @@ select = [
     # https://docs.astral.sh/ruff/rules/#flake8-type-checking-tch
     "TCH001", 
     "TCH002", 
-    "TCH003", 
+    "TCH003",
+    "FA100", # future-rewritable-type-annotation
+    "FA102", # future-required-type-annotation 
 ]
 [tool.ruff.lint.per-file-ignores]
 "src/project/settings/*" = ["F405"]
-"src/lib/chess_engines/sunfish/sunfish.py" = ["F841", "F821"]
 
 [tool.ruff.lint.isort]
 # https://docs.astral.sh/ruff/settings/#lintisort

scripts/download_assets.py

@@ -1,4 +1,5 @@
 #!/usr/bin/env python
+from __future__ import annotations
 
 import asyncio
 from pathlib import Path
@@ -83,7 +84,7 @@
 
 
 async def download_assets(*, even_if_exists: bool) -> None:
-    download_coros: list["Coroutine"] = []
+    download_coros: list[Coroutine] = []
 
     limits = httpx.Limits(
         max_connections=DOWNLOADS_CONCURRENCY,

src/apps/chess/business_logic/_calculate_fen_before_move.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from typing import TYPE_CHECKING
 
 import chess
@@ -11,10 +13,10 @@
 def calculate_fen_before_move(
     # TODO: change move_uci to a MoveTuple type
     *,
-    fen_after_move: "FEN",
+    fen_after_move: FEN,
     move_uci: str,
-    moving_player_side: "PlayerSide",
-) -> "FEN":
+    moving_player_side: PlayerSide,
+) -> FEN:
     """
     Calculate the FEN of the chess board before the given move.
     Raises a ValueError if the move is invalid.

src/apps/chess/business_logic/_calculate_piece_available_targets.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from typing import TYPE_CHECKING
 
 import chess
@@ -9,10 +11,10 @@
 
 
 def calculate_piece_available_targets(
-    *, chess_board: chess.Board, piece_square: "Square"
-) -> frozenset["Square"]:
+    *, chess_board: chess.Board, piece_square: Square
+) -> frozenset[Square]:
     square_index = chess.parse_square(piece_square)
-    result: list["Square"] = []
+    result: list[Square] = []
     for move in chess_board.legal_moves:
         if move.from_square == square_index:
             result.append(chess_lib_square_to_square(move.to_square))

src/apps/chess/business_logic/_do_chess_move.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from typing import TYPE_CHECKING, Literal, cast
 
 import chess
@@ -18,12 +20,12 @@
 
     from apps.chess.types import FEN, GameEndReason, MoveTuple, PlayerSide, Rank, Square
 
-_CHESS_COLOR_TO_PLAYER_SIDE_MAPPING: "Mapping[chess.Color, PlayerSide]" = {
+_CHESS_COLOR_TO_PLAYER_SIDE_MAPPING: Mapping[chess.Color, PlayerSide] = {
     True: "w",
     False: "b",
 }
 
-_CHESS_OUTCOME_TO_GAME_END_REASON_MAPPING: "Mapping[chess.Termination, GameEndReason]" = {
+_CHESS_OUTCOME_TO_GAME_END_REASON_MAPPING: Mapping[chess.Termination, GameEndReason] = {
     chess.Termination.CHECKMATE: "checkmate",
     chess.Termination.STALEMATE: "stalemate",
     chess.Termination.INSUFFICIENT_MATERIAL: "insufficient_material",
@@ -44,15 +46,15 @@
     ("e8", "c8"),
 )
 
-_CASTLING_ROOK_MOVE: "Mapping[_CastlingPossibleTo, tuple[Square, Square]]" = {
+_CASTLING_ROOK_MOVE: Mapping[_CastlingPossibleTo, tuple[Square, Square]] = {
     # {king new square: (rook previous square, rook new square)} dict:
     "g1": ("h1", "f1"),
     "c1": ("a1", "d1"),
     "g8": ("h8", "f8"),
     "c8": ("a8", "d8"),
 }
 
-_EN_PASSANT_CAPTURED_PIECES_RANK_CONVERSION: dict["Rank", "Rank"] = {
+_EN_PASSANT_CAPTURED_PIECES_RANK_CONVERSION: dict[Rank, Rank] = {
     # if a pawn was captured by en passant targeting a6, its position on the board
     # before at the moment it's been captured was a5:
     "6": "5",
@@ -63,9 +65,9 @@
 
 def do_chess_move(
     *,
-    from_: "Square",
-    to: "Square",
-    fen: "FEN | None" = None,
+    from_: Square,
+    to: Square,
+    fen: FEN | None = None,
     chess_board: chess.Board | None = None,
 ) -> ChessMoveResult:
     """
@@ -77,8 +79,8 @@ def do_chess_move(
             "You must provide either a FEN string or a `chess.Board` object"
         )
 
-    moves: list["MoveTuple"] = []
-    captured: "Square | None" = None
+    moves: list[MoveTuple] = []
+    captured: Square | None = None
 
     if not chess_board:
         chess_board = chess.Board(fen)

src/apps/chess/business_logic/_do_chess_move_with_piece_role_by_square.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from typing import TYPE_CHECKING, NamedTuple, cast
 
 from ..chess_helpers import (
@@ -20,18 +22,18 @@
 
 
 class ChessMoveWithPieceRoleBySquareResult(NamedTuple):
-    move_result: "ChessMoveResult"
-    piece_role_by_square: "PieceRoleBySquare"
-    captured_piece: "PieceRole | None"
+    move_result: ChessMoveResult
+    piece_role_by_square: PieceRoleBySquare
+    captured_piece: PieceRole | None
 
 
 def do_chess_move_with_piece_role_by_square(
     *,
-    from_: "Square",
-    to: "Square",
-    piece_role_by_square: "PieceRoleBySquare",
-    fen: "FEN | None" = None,
-    chess_board: "chess.Board | None" = None,
+    from_: Square,
+    to: Square,
+    piece_role_by_square: PieceRoleBySquare,
+    fen: FEN | None = None,
+    chess_board: chess.Board | None = None,
 ) -> ChessMoveWithPieceRoleBySquareResult:
     from ._do_chess_move import do_chess_move
 
@@ -63,7 +65,7 @@ def do_chess_move_with_piece_role_by_square(
         )
         piece_role_by_square[from_] += piece_promotion  # type: ignore
 
-    captured_piece: "PieceRole | None" = None
+    captured_piece: PieceRole | None = None
     if captured := move_result["captured"]:
         assert move_result["is_capture"]
         captured_piece = piece_role_by_square[captured]