Use a fully locked test environment (#1349)

* Use dependency groups & a fully locked dev environment

* update lockfile

* Update contributing guide

Author: hynek

.github/CONTRIBUTING.md

@@ -52,42 +52,36 @@ First, **fork** the repository on GitHub and **clone** it using one of the alter
 You can (and should) run our test suite using [*tox*](https://tox.wiki/).
 However, you'll probably want a more traditional environment as well.
 
-We recommend using the Python version from the `.python-version-default` file in the project's root directory, because that's the one that is used in the CI by default, too.
+We recommend using the Python version from the `.python-version-default` file in the project's root directory.
 
-If you're using [*direnv*](https://direnv.net), you can automate the creation of the project virtual environment with the correct Python version by adding the following `.envrc` to the project root:
+We use a fully-locked development environment using [*uv*](https://docs.astral.sh/uv/) so the easiest way to get started is to [install *uv*](https://docs.astral.sh/uv/getting-started/installation/) and you can run `uv run pytest` to run the tests immediately.
+
+I you'd like a traditional virtual environment, you can run `uv sync` and it will create a virtual environment named `.venv` with the correct Python version and install all the dependencies in the root directory.
+
+If you're using [*direnv*](https://direnv.net), you can automate the creation and activation of the project's virtual environment with the correct Python version by adding the following `.envrc` to the project root:
 
 ```bash
-layout python python$(cat .python-version-default)
+uv sync
+. .venv/bin/activate
 ```
 
-or, if you like [*uv*](https://github.com/astral-sh/uv):
+---
+
+If you don't want to use *uv*, you can use Pip 25.1 (that added support for dependency groups) or newer and install the dependencies manually:
 
 ```bash
-test -d .venv || uv venv --python python$(cat .python-version-default)
-. .venv/bin/activate
+pip install -e . --group dev
 ```
 
+---
+
 > [!WARNING]
 > - **Before** you start working on a new pull request, use the "*Sync fork*" button in GitHub's web UI to ensure your fork is up to date.
 >
 > - **Always create a new branch off `main` for each new pull request.**
 >   Yes, you can work on `main` in your fork and submit pull requests.
 >   But this will *inevitably* lead to you not being able to synchronize your fork with upstream and having to start over.
 
-Change into the newly created directory and after activating a virtual environment, install an editable version of this project along with its tests requirements:
-
-```console
-$ pip install -e .[dev]  # or `uv pip install -e .[dev]`
-```
-
-Now you can run the test suite:
-
-```console
-$ python -Im pytest
-```
-
-You can *significantly* speed up the test suite by passing `-n auto` to *pytest* which activates [*pytest-xdist*](https://github.com/pytest-dev/pytest-xdist) and takes advantage of all your CPU cores.
-
 ---
 
 When working on the documentation, use:
@@ -123,7 +117,6 @@ $ tox run -e docs-doctests
 - If you've changed or added public APIs, please update our type stubs (files ending in `.pyi`).
 
 
-
 ## Tests
 
 - Write your asserts as `expected == actual` to line them up nicely, and leave an empty line before them:

pyproject.toml

@@ -10,12 +10,11 @@ name = "attrs"
 authors = [{ name = "Hynek Schlawack", email = "[email protected]" }]
 license = "MIT"
 license-files = ["LICENSE"]
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 description = "Classes Without Boilerplate"
 keywords = ["class", "attribute", "boilerplate"]
 classifiers = [
   "Development Status :: 5 - Production/Stable",
-  "Programming Language :: Python :: 3.8",
   "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
@@ -29,7 +28,15 @@ classifiers = [
 dependencies = []
 dynamic = ["version", "readme"]
 
-[project.optional-dependencies]
+[project.urls]
+Documentation = "https://www.attrs.org/"
+Changelog = "https://www.attrs.org/en/stable/changelog.html"
+GitHub = "https://github.com/python-attrs/attrs"
+Funding = "https://github.com/sponsors/hynek"
+Tidelift = "https://tidelift.com/subscription/pkg/pypi-attrs?utm_source=pypi-attrs&utm_medium=pypi"
+
+
+[dependency-groups]
 tests-mypy = [
   # A transitive dependency of pytest-mypy-plugins doesn't build on 3.14 yet.
   'pytest-mypy-plugins; platform_python_implementation == "CPython" and python_version >= "3.10" and python_version < "3.14"',
@@ -38,21 +45,25 @@ tests-mypy = [
   'mypy>=1.11.1; platform_python_implementation == "CPython" and python_version >= "3.10"',
 ]
 tests = [
+  { include-group = "tests-mypy" },
   # For regression test to ensure cloudpickle compat doesn't break.
   'cloudpickle; platform_python_implementation == "CPython"',
   "hypothesis",
   "pympler",
   # 4.3.0 dropped last use of `convert`
   "pytest>=4.3.0",
-  "pytest-xdist[psutil]",
-  "attrs[tests-mypy]",
 ]
 cov = [
-  "attrs[tests]",
+  { include-group = "tests" },
   # Ensure coverage is new enough for `source_pkgs`.
   "coverage[toml]>=5.3",
 ]
-benchmark = ["pytest-codspeed", "pytest-xdist[psutil]", "attrs[tests]"]
+pyright = ["pyright", { include-group = "tests" }]
+benchmark = [
+  { include-group = "tests" },
+  "pytest-codspeed",
+  "pytest-xdist[psutil]",
+]
 docs = [
   "cogapp",
   "furo",
@@ -62,14 +73,8 @@ docs = [
   "sphinxcontrib-towncrier",
   "towncrier",
 ]
-dev = ["attrs[tests]", "pre-commit-uv"]
-
-[project.urls]
-Documentation = "https://www.attrs.org/"
-Changelog = "https://www.attrs.org/en/stable/changelog.html"
-GitHub = "https://github.com/python-attrs/attrs"
-Funding = "https://github.com/sponsors/hynek"
-Tidelift = "https://tidelift.com/subscription/pkg/pypi-attrs?utm_source=pypi-attrs&utm_medium=pypi"
+docs-watch = [{ include-group = "docs" }, "watchfiles"]
+dev = [{ include-group = "tests" }]
 
 
 [tool.hatch.version]
@@ -227,6 +232,8 @@ ignore = [
   "TD",      # we don't follow other people's todo style
   "TRY301",  # I'm sorry, but this makes not sense for us.
   "UP031",   # format() is slow as molasses; % and f'' FTW.
+  "UP006",   # replace Dict etc by dict etc later.
+  "UP035",   # replace Dict etc by dict etc later.
 ]
 
 [tool.ruff.lint.per-file-ignores]
@@ -254,10 +261,10 @@ ignore = [
 "src/*/*.pyi" = ["ALL"] # TODO
 "tests/test_annotations.py" = ["FA100"]
 "tests/typing_example.py" = [
-  "E741",   # ambiguous variable names don't matter in type checks
-  "B018",   # useless expressions aren't useless in type checks
-  "B015",   # pointless comparison in type checks aren't pointless
-  "UP037",  # we test some older syntaxes on purpose
+  "E741",  # ambiguous variable names don't matter in type checks
+  "B018",  # useless expressions aren't useless in type checks
+  "B015",  # pointless comparison in type checks aren't pointless
+  "UP037", # we test some older syntaxes on purpose
 ]
 
 [tool.ruff.lint.isort]

src/attr/_compat.py

@@ -10,7 +10,6 @@
 
 
 PYPY = platform.python_implementation() == "PyPy"
-PY_3_9_PLUS = sys.version_info[:2] >= (3, 9)
 PY_3_10_PLUS = sys.version_info[:2] >= (3, 10)
 PY_3_11_PLUS = sys.version_info[:2] >= (3, 11)
 PY_3_12_PLUS = sys.version_info[:2] >= (3, 12)

src/attr/_funcs.py

@@ -3,7 +3,7 @@
 
 import copy
 
-from ._compat import PY_3_9_PLUS, get_generic_base
+from ._compat import get_generic_base
 from ._make import _OBJ_SETATTR, NOTHING, fields
 from .exceptions import AttrsAttributeNotFoundError
 
@@ -450,10 +450,11 @@ class yet.
     if getattr(cls, "__attrs_types_resolved__", None) != cls:
         import typing
 
-        kwargs = {"globalns": globalns, "localns": localns}
-
-        if PY_3_9_PLUS:
-            kwargs["include_extras"] = include_extras
+        kwargs = {
+            "globalns": globalns,
+            "localns": localns,
+            "include_extras": include_extras,
+        }
 
         hints = typing.get_type_hints(cls, **kwargs)
         for field in fields(cls) if attribs is None else attribs:

tox.ini

@@ -3,7 +3,7 @@ min_version = 4
 # Mypy doesn't run on 3.14 yet.
 env_list =
     pre-commit,
-    py3{8,9,10,11,12,13,14}-tests,
+    py3{9,10,11,12,13,14}-tests,
     py3{10,11,12,13}-mypy,
     pypy3-tests,
     pyright,
@@ -17,45 +17,46 @@ pass_env = SETUPTOOLS_SCM_PRETEND_VERSION
 
 
 [testenv]
+runner = uv-venv-lock-runner
 package = wheel
 wheel_build_env = .pkg
-extras =
+dependency_groups =
     tests: tests
     mypy: tests-mypy
 commands =
-    tests: pytest {posargs:-n auto}
+    tests: pytest {posargs}
     mypy: mypy tests/typing_example.py
     mypy: mypy src/attrs/__init__.pyi src/attr/__init__.pyi src/attr/_typing_compat.pyi src/attr/_version_info.pyi src/attr/converters.pyi src/attr/exceptions.pyi src/attr/filters.pyi src/attr/setters.pyi src/attr/validators.pyi
 
 [testenv:pypy3-tests]
-extras = tests
+dependency_groups = tests
 commands = pytest tests/test_functional.py
 
-[testenv:py3{8,10,13}-tests]
-extras = cov
+[testenv:py3{9,10,13}-tests]
+dependency_groups = cov
 # Python 3.6+ has a number of compile-time warnings on invalid string escapes.
 # PYTHONWARNINGS=d makes them visible during the tox run.
 set_env =
     COVERAGE_PROCESS_START={toxinidir}/pyproject.toml
     PYTHONWARNINGS=d
 commands_pre = python -c 'import pathlib; pathlib.Path("{env_site_packages_dir}/cov.pth").write_text("import coverage; coverage.process_startup()")'
-# We group xdist execution by file because otherwise the Mypy tests have race conditions.
-commands = coverage run -m pytest {posargs:-n auto --dist loadfile}
+commands =
+    coverage run -m pytest {posargs}
 
 [testenv:coverage-report]
 # Keep base_python in-sync with .python-version-default
 base_python = py313
-# Keep depends in-sync with testenv above that has cov extra.
-depends = py3{8,10,13}-tests
+# Keep depends in-sync with testenv above that has the cov dependency group.
+depends = py3{9,10,13}-tests
 skip_install = true
-deps = coverage[toml]>=5.3
+dependency_groups = cov
 commands =
     coverage combine
     coverage report
 
 
 [testenv:codspeed]
-extras = benchmark
+dependency_groups = benchmark
 pass_env =
     CODSPEED_TOKEN
     CODSPEED_ENV
@@ -66,9 +67,10 @@ commands = pytest --codspeed -n auto bench/test_benchmarks.py
 
 
 [testenv:docs-{build,doctests,linkcheck}]
-# Keep base_python in sync with .readthedocs.yaml.
+runner = uv-venv-lock-runner
+# Keep base_python in-sync with .readthedocs.yaml.
 base_python = py313
-extras = docs
+dependency_groups = docs
 commands =
     build: sphinx-build -n -T -W -b html -d {envtmpdir}/doctrees docs {posargs:docs/_build/}html
     doctests: sphinx-build -n -T -W -b doctest -d {envtmpdir}/doctrees docs {posargs:docs/_build/}html
@@ -77,46 +79,48 @@ commands =
 [testenv:docs-watch]
 package = editable
 base_python = {[testenv:docs-build]base_python}
-extras = {[testenv:docs-build]extras}
+dependency_groups = docs-watch
 deps = watchfiles
 commands =
     watchfiles \
         --ignore-paths docs/_build/ \
         'sphinx-build -W -n --jobs auto -b html -d {envtmpdir}/doctrees docs docs/_build/html' \
+        README.md \
         src \
         docs
 
 [testenv:docs-sponsors]
+runner = uv-venv-runner
+skip_install = true
 description = Ensure sponsor logos are up to date.
 deps = cogapp
 commands = cog -rP README.md docs/index.md
 
 
 [testenv:pre-commit]
+runner = uv-venv-runner
 skip_install = true
 deps = pre-commit-uv
 commands = pre-commit run --all-files
 
 
 [testenv:changelog]
-# See https://github.com/sphinx-contrib/sphinxcontrib-towncrier/issues/92
-# Pin also present in pyproject.toml
-deps = towncrier
+dependency_groups = docs
 skip_install = true
 commands =
     towncrier --version
     towncrier build --version main --draft
 
 
 [testenv:pyright]
-extras = tests
-deps = pyright>=1.1.380
+dependency_groups = pyright
 commands = pytest tests/test_pyright.py -vv
 
 
 [testenv:docset]
+runner = uv-venv-runner
 deps = doc2dash
-extras = docs
+dependency_groups = docs
 allowlist_externals =
     rm
     cp