deps!(python): drop Python 3.7 support and mark some arguments as positional-only

.github/workflows/build.yml

@@ -49,7 +49,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
-          python-version: "3.7 - 3.13"
+          python-version: "3.8 - 3.13"
           update-environment: true
 
       - name: Upgrade pip
@@ -88,21 +88,24 @@ jobs:
       matrix:
         runner: [ubuntu-latest, windows-latest, macos-latest]
         python-version:
-          ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "3.13t", "pypy-3.9", "pypy-3.10"]
-        archs: [
-            # Generic
-            "auto",
-            # Linux
-            "aarch64",
-            "ppc64le",
-            "s390x",
-            # Windows
-            "ARM64",
-          ]
-        include:
-          - runner: macos-13
-            python-version: "3.7"
-            archs: "auto"
+          - "3.8"
+          - "3.9"
+          - "3.10"
+          - "3.11"
+          - "3.12"
+          - "3.13"
+          - "3.13t"
+          - "pypy-3.9"
+          - "pypy-3.10"
+        archs:
+          # Generic
+          - "auto"
+          # Linux
+          - "aarch64"
+          - "ppc64le"
+          - "s390x"
+          # Windows
+          - "ARM64"
         exclude:
           - runner: ubuntu-latest
             python-version: "pypy-3.9"
@@ -116,9 +119,6 @@ jobs:
           - runner: ubuntu-latest
             python-version: "pypy-3.10"
             archs: "s390x"
-          - runner: windows-latest
-            python-version: "3.7"
-            archs: "ARM64"
           - runner: windows-latest
             python-version: "3.8"
             archs: "ARM64"
@@ -128,8 +128,6 @@ jobs:
           - runner: windows-latest
             python-version: "pypy-3.10"
             archs: "ARM64"
-          - runner: macos-latest
-            python-version: "3.7"  # Python 3.7 does not support macOS ARM64
 
           # Exclude archs of other platforms
           - runner: ubuntu-latest
@@ -271,7 +269,7 @@ jobs:
         if: startsWith(github.ref, 'refs/tags/')
         uses: actions/setup-python@v5
         with:
-          python-version: "3.7 - 3.13"
+          python-version: "3.8 - 3.13"
           update-environment: true
 
       - name: Upgrade pip

.github/workflows/tests-with-pydebug.yml

@@ -36,11 +36,15 @@ jobs:
     strategy:
       matrix:
         runner: [ubuntu-latest, windows-latest, macos-latest]
-        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
+        python-version:
+          - "3.8"
+          - "3.9"
+          - "3.10"
+          - "3.11"
+          - "3.12"
+          - "3.13"
         python-abiflags: ["d", "td"]
         exclude:
-          - python-version: "3.7"
-            python-abiflags: "td"
           - python-version: "3.8"
             python-abiflags: "td"
           - python-version: "3.9"

.github/workflows/tests.yml

@@ -38,13 +38,14 @@ jobs:
       matrix:
         runner: [ubuntu-latest, windows-latest, macos-latest]
         python-version:
-          ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "pypy-3.9", "pypy-3.10"]
-        include:
-          - runner: macos-13
-            python-version: "3.7"
-        exclude:
-          - runner: macos-latest
-            python-version: "3.7"  # Python 3.7 does not support macOS ARM64
+          - "3.8"
+          - "3.9"
+          - "3.10"
+          - "3.11"
+          - "3.12"
+          - "3.13"
+          - "pypy-3.9"
+          - "pypy-3.10"
       fail-fast: false
     timeout-minutes: 90
     steps:
@@ -62,11 +63,6 @@ jobs:
         run: |
           python -m pip install --upgrade pip setuptools wheel
 
-      - name: Set `SETUPTOOLS_ENABLE_FEATURES`
-        if: ${{ matrix.python-version == '3.7' && runner.os == 'Windows' }}
-        run: |
-          Write-Output 'SETUPTOOLS_ENABLE_FEATURES=legacy-editable' | Out-File -FilePath $Env:GITHUB_ENV -Encoding utf8 -Append
-
       - name: Install test dependencies
         shell: bash
         run: |

.pre-commit-config.yaml

@@ -43,10 +43,10 @@ repos:
     hooks:
       - id: black
   - repo: https://github.com/asottile/pyupgrade
-    rev: v3.18.0
+    rev: v3.19.0
     hooks:
       - id: pyupgrade
-        args: [--py37-plus]
+        args: [--py38-plus]
   - repo: https://github.com/pycqa/flake8
     rev: 7.1.1
     hooks:

CHANGELOG.md

@@ -17,15 +17,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
--
+- Mark some arguments as positional-only by [@XuehaiPan](https://github.com/XuehaiPan) in [#161](https://github.com/metaopt/optree/pull/161).
 
 ### Fixed
 
 -
 
 ### Removed
 
--
+- Drop Python 3.6 support by [@XuehaiPan](https://github.com/XuehaiPan) in [#161](https://github.com/metaopt/optree/pull/161).
 
 ------
 

CONTRIBUTING.md

@@ -88,13 +88,13 @@ python3 -m cibuildwheel --platform=linux --output-dir=wheelhouse --config-file=p
 It will build wheel binaries for all supported CPython versions. The outputs will be placed in the `wheelhouse` directory.
 
 To build a wheel for a specific CPython version, you can use the [`CIBW_BUILD`](https://cibuildwheel.readthedocs.io/en/stable/options/#build-skip) environment variable.
-For example, the following command will build a wheel for Python 3.7:
+For example, the following command will build a wheel for Python 3.9:
 
 ```bash
-CIBW_BUILD="cp37*manylinux*" python3 -m cibuildwheel --platform=linux --output-dir=wheelhouse --config-file=pyproject.toml
+CIBW_BUILD="cp39*manylinux*" python3 -m cibuildwheel --platform=linux --output-dir=wheelhouse --config-file=pyproject.toml
 ```
 
-You can change `cp37*` to `cp310*` to build for Python 3.10. See <https://cibuildwheel.readthedocs.io/en/stable/options> for more options.
+You can change `cp39*` to `cp312*` to build for Python 3.12. See <https://cibuildwheel.readthedocs.io/en/stable/options> for more options.
 
 ## Documentation
 

Makefile

@@ -88,11 +88,7 @@ pre-commit-install:
 .PHONY: docs-install
 docs-install:
 	$(call check_pip_install_extra,pydocstyle,pydocstyle[toml])
-	$(call check_pip_install_extra,doc8,"doc8<1.0.0a0")  # unpin this when we drop support for Python 3.7
-	if ! $(PYTHON) -c "import sys; exit(sys.version_info < (3, 8))"; then \
-		$(PYTHON) -m pip uninstall --yes importlib-metadata; \
-		$(call check_pip_install_extra,importlib-metadata,"importlib-metadata<5.0.0a0"); \
-	fi
+	$(call check_pip_install,doc8)
 	$(call check_pip_install,sphinx)
 	$(call check_pip_install,sphinx-rtd-theme)
 	$(call check_pip_install,sphinx-autoapi)

README.md

@@ -2,7 +2,7 @@
 
 # OpTree
 
-![Python 3.7+](https://img.shields.io/badge/Python-3.7%2B-brightgreen)
+![Python 3.8+](https://img.shields.io/badge/Python-3.8%2B-brightgreen)
 [![PyPI](https://img.shields.io/pypi/v/optree?logo=pypi)](https://pypi.org/project/optree)
 ![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/metaopt/optree/build.yml?label=build&logo=github)
 ![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/metaopt/optree/tests.yml?label=tests&logo=github)
@@ -67,7 +67,7 @@ cd optree
 pip3 install .
 ```
 
-Compiling from the source requires Python 3.7+, a compiler (`gcc` / `clang` / `icc` / `cl.exe`) that supports C++20 and a `cmake` installation.
+Compiling from the source requires Python 3.8+, a compiler (`gcc` / `clang` / `icc` / `cl.exe`) that supports C++20 and a `cmake` installation.
 
 --------------------------------------------------------------------------------
 

optree/_C.pyi

@@ -43,12 +43,14 @@ GLIBCXX_USE_CXX11_ABI: bool
 
 def flatten(
     tree: PyTree[T],
+    /,
     leaf_predicate: Callable[[T], bool] | None = None,
     node_is_leaf: bool = False,
     namespace: str = '',
 ) -> tuple[list[T], PyTreeSpec]: ...
 def flatten_with_path(
     tree: PyTree[T],
+    /,
     leaf_predicate: Callable[[T], bool] | None = None,
     node_is_leaf: bool = False,
     namespace: str = '',
@@ -63,29 +65,32 @@ def make_none(
 ) -> PyTreeSpec: ...
 def make_from_collection(
     collection: Collection[PyTreeSpec],
+    /,
     node_is_leaf: bool = False,
     namespace: str = '',
 ) -> PyTreeSpec: ...
 def is_leaf(
     obj: T,
+    /,
     leaf_predicate: Callable[[T], bool] | None = None,
     node_is_leaf: bool = False,
     namespace: str = '',
 ) -> bool: ...
 def all_leaves(
     iterable: Iterable[T],
+    /,
     leaf_predicate: Callable[[T], bool] | None = None,
     node_is_leaf: bool = False,
     namespace: str = '',
 ) -> bool: ...
-def is_namedtuple(obj: object | type) -> bool: ...
-def is_namedtuple_instance(obj: object) -> bool: ...
-def is_namedtuple_class(cls: type) -> bool: ...
-def namedtuple_fields(obj: tuple | type[tuple]) -> tuple[str, ...]: ...
-def is_structseq(obj: object | type) -> bool: ...
-def is_structseq_instance(obj: object) -> bool: ...
-def is_structseq_class(cls: type) -> bool: ...
-def structseq_fields(obj: tuple | type[tuple]) -> tuple[str, ...]: ...
+def is_namedtuple(obj: object | type, /) -> bool: ...
+def is_namedtuple_instance(obj: object, /) -> bool: ...
+def is_namedtuple_class(cls: type, /) -> bool: ...
+def namedtuple_fields(obj: tuple | type[tuple], /) -> tuple[str, ...]: ...
+def is_structseq(obj: object | type, /) -> bool: ...
+def is_structseq_instance(obj: object, /) -> bool: ...
+def is_structseq_class(cls: type, /) -> bool: ...
+def structseq_fields(obj: tuple | type[tuple], /) -> tuple[str, ...]: ...
 
 class PyTreeKind(enum.IntEnum):
     CUSTOM = 0  # a custom type
@@ -108,54 +113,58 @@ class PyTreeSpec:
     namespace: str
     type: builtins.type | None
     kind: PyTreeKind
-    def unflatten(self, leaves: Iterable[T]) -> PyTree[T]: ...
-    def flatten_up_to(self, full_tree: PyTree[T]) -> list[PyTree[T]]: ...
-    def broadcast_to_common_suffix(self, other: PyTreeSpec) -> PyTreeSpec: ...
-    def compose(self, inner_treespec: PyTreeSpec) -> PyTreeSpec: ...
+    def unflatten(self, leaves: Iterable[T], /) -> PyTree[T]: ...
+    def flatten_up_to(self, full_tree: PyTree[T], /) -> list[PyTree[T]]: ...
+    def broadcast_to_common_suffix(self, other: Self, /) -> Self: ...
+    def compose(self, inner_treespec: Self, /) -> Self: ...
     def walk(
         self,
+        /,
         f_node: Callable[[tuple[U, ...], MetaData], U],
         f_leaf: Callable[[T], U] | None,
         leaves: Iterable[T],
     ) -> U: ...
-    def paths(self) -> list[tuple[Any, ...]]: ...
-    def accessors(self) -> list[PyTreeAccessor]: ...
-    def entries(self) -> list[Any]: ...
-    def entry(self, index: int) -> Any: ...
-    def children(self) -> list[PyTreeSpec]: ...
-    def child(self, index: int) -> PyTreeSpec: ...
-    def is_leaf(self, strict: bool = True) -> bool: ...
-    def is_prefix(self, other: PyTreeSpec, strict: bool = False) -> bool: ...
-    def is_suffix(self, other: PyTreeSpec, strict: bool = False) -> bool: ...
-    def __eq__(self, other: object) -> bool: ...
-    def __ne__(self, other: object) -> bool: ...
-    def __lt__(self, other: object) -> bool: ...
-    def __le__(self, other: object) -> bool: ...
-    def __gt__(self, other: object) -> bool: ...
-    def __ge__(self, other: object) -> bool: ...
-    def __hash__(self) -> int: ...
-    def __len__(self) -> int: ...
+    def paths(self, /) -> list[tuple[Any, ...]]: ...
+    def accessors(self, /) -> list[PyTreeAccessor]: ...
+    def entries(self, /) -> list[Any]: ...
+    def entry(self, index: int, /) -> Any: ...
+    def children(self, /) -> list[Self]: ...
+    def child(self, index: int, /) -> Self: ...
+    def is_leaf(self, /, strict: bool = True) -> bool: ...
+    def is_prefix(self, other: Self, /, strict: bool = False) -> bool: ...
+    def is_suffix(self, other: Self, /, strict: bool = False) -> bool: ...
+    def __eq__(self, other: object, /) -> bool: ...
+    def __ne__(self, other: object, /) -> bool: ...
+    def __lt__(self, other: object, /) -> bool: ...
+    def __le__(self, other: object, /) -> bool: ...
+    def __gt__(self, other: object, /) -> bool: ...
+    def __ge__(self, other: object, /) -> bool: ...
+    def __hash__(self, /) -> int: ...
+    def __len__(self, /) -> int: ...
 
 class PyTreeIter(Iterator[T]):
     def __init__(
         self,
         tree: PyTree[T],
+        /,
         leaf_predicate: Callable[[T], bool] | None = None,
         node_is_leaf: bool = False,
         namespace: str = '',
     ) -> None: ...
-    def __iter__(self) -> Self: ...
-    def __next__(self) -> T: ...
+    def __iter__(self, /) -> Self: ...
+    def __next__(self, /) -> T: ...
 
 def register_node(
     cls: type[Collection[T]],
+    /,
     flatten_func: FlattenFunc[T],
     unflatten_func: UnflattenFunc[T],
     path_entry_type: type[PyTreeEntry],
     namespace: str = '',
 ) -> None: ...
 def unregister_node(
     cls: type,
+    /,
     namespace: str = '',
 ) -> None: ...
 def is_dict_insertion_ordered(
@@ -164,5 +173,6 @@ def is_dict_insertion_ordered(
 ) -> bool: ...
 def set_dict_insertion_ordered(
     mode: bool,
+    /,
     namespace: str = '',
 ) -> None: ...