Switch build backend to Hatchling

.github/workflows/diff_shades.yml

@@ -3,10 +3,10 @@ name: diff-shades
 on:
   push:
     branches: [main]
-    paths: ["src/**", "setup.*", "pyproject.toml", ".github/workflows/*"]
+    paths: ["src/**", "pyproject.toml", ".github/workflows/*"]
 
   pull_request:
-    paths: ["src/**", "setup.*", "pyproject.toml", ".github/workflows/*"]
+    paths: ["src/**", "pyproject.toml", ".github/workflows/*"]
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_id }}
@@ -41,6 +41,7 @@ jobs:
     needs: configure
     runs-on: ubuntu-latest
     env:
+      HATCH_BUILD_HOOKS_ENABLE: "1"
       # Clang is less picky with the C code it's given than gcc (and may
       # generate faster binaries too).
       CC: clang-12
@@ -64,7 +65,6 @@ jobs:
         run: |
           python -m pip install https://github.com/ichard26/diff-shades/archive/stable.zip
           python -m pip install click packaging urllib3
-          python -m pip install -r .github/mypyc-requirements.txt
           # After checking out old revisions, this might not exist so we'll use a copy.
           cat scripts/diff_shades_gha_helper.py > helper.py
           git config user.name "diff-shades-gha"
@@ -83,8 +83,7 @@ jobs:
           GITHUB_TOKEN: ${{ github.token }}
         run: >
           ${{ matrix.baseline-setup-cmd }}
-          && python setup.py --use-mypyc bdist_wheel
-          && python -m pip install dist/*.whl && rm build dist -r
+          && python -m pip install .
 
       - name: Analyze baseline revision
         if: steps.baseline-cache.outputs.cache-hit != 'true'
@@ -97,8 +96,7 @@ jobs:
           GITHUB_TOKEN: ${{ github.token }}
         run: >
           ${{ matrix.target-setup-cmd }}
-          && python setup.py --use-mypyc bdist_wheel
-          && python -m pip install dist/*.whl
+          && python -m pip install .
 
       - name: Analyze target revision
         run: >

.github/workflows/fuzz.yml

@@ -22,7 +22,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.7", "3.8", "3.9", "3.10"]
 
     steps:
       - uses: actions/checkout@v3

.github/workflows/pypi_upload.yml

@@ -61,8 +61,6 @@ jobs:
         uses: pypa/cibuildwheel@v2.10.0
         env:
           CIBW_ARCHS_MACOS: "${{ matrix.macos_arch }}"
-          # This isn't supported in pyproject.toml which makes sense (but is annoying).
-          CIBW_PROJECT_REQUIRES_PYTHON: ">=3.6.2"
 
       - name: Upload wheels as workflow artifacts
         uses: actions/upload-artifact@v2

.github/workflows/test.yml

@@ -31,7 +31,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.6", "3.7", "3.8", "3.9", "3.10", "pypy-3.7", "pypy-3.8"]
+        python-version: ["3.7", "3.8", "3.9", "3.10", "pypy-3.7", "pypy-3.8"]
         os: [ubuntu-latest, macOS-latest, windows-latest]
 
     steps:

CHANGES.md

@@ -6,6 +6,9 @@
 
 <!-- Include any especially major or disruptive changes here -->
 
+- Runtime support for Python 3.6 has been removed. Formatting 3.6 code will still be
+  supported until further notice.
+
 ### Stable style
 
 <!-- Changes that affect Black's stable style -->
@@ -25,6 +28,8 @@
 
 <!-- Changes to how Black is packaged, such as dependency requirements -->
 
+- Hatchling is now used as the build backend. This will not have any effect for users
+  who install Black with its wheels from PyPI. (#3233)
 - Faster compiled wheels are now available for CPython 3.11 (#3276)
 
 ### Parser

docs/usage_and_configuration/the_basics.md

@@ -204,9 +204,10 @@ code in compliance with many other _Black_ formatted projects.
 
 [PEP 518](https://www.python.org/dev/peps/pep-0518/) defines `pyproject.toml` as a
 configuration file to store build system requirements for Python projects. With the help
-of tools like [Poetry](https://python-poetry.org/) or
-[Flit](https://flit.readthedocs.io/en/latest/) it can fully replace the need for
-`setup.py` and `setup.cfg` files.
+of tools like [Poetry](https://python-poetry.org/),
+[Flit](https://flit.readthedocs.io/en/latest/), or
+[Hatch](https://hatch.pypa.io/latest/) it can fully replace the need for `setup.py` and
+`setup.cfg` files.
 
 ### Where _Black_ looks for the file
 

pyproject.toml

@@ -7,7 +7,7 @@
 
 [tool.black]
 line-length = 88
-target-version = ['py36', 'py37', 'py38']
+target-version = ['py37', 'py38']
 include = '\.pyi?$'
 extend-exclude = '''
 /(
@@ -26,18 +26,128 @@ preview = true
 # NOTE: You don't need this in your own Black configuration.
 
 [build-system]
-requires = ["setuptools>=45.0", "setuptools_scm[toml]>=6.3.1", "wheel"]
-build-backend = "setuptools.build_meta"
+requires = ["hatchling>=1.8.0", "hatch-vcs", "hatch-fancy-pypi-readme"]
+build-backend = "hatchling.build"
+
+[project]
+name = "black"
+description = "The uncompromising code formatter."
+license = "MIT"
+requires-python = ">=3.7"
+authors = [
+  { name = "Łukasz Langa", email = "lukasz@langa.pl" },
+]
+keywords = [
+  "automation",
+  "autopep8",
+  "formatter",
+  "gofmt",
+  "pyfmt",
+  "rustfmt",
+  "yapf",
+]
+classifiers = [
+  "Development Status :: 5 - Production/Stable",
+  "Environment :: Console",
+  "Intended Audience :: Developers",
+  "License :: OSI Approved :: MIT License",
+  "Operating System :: OS Independent",
+  "Programming Language :: Python",
+  "Programming Language :: Python :: 3 :: Only",
+  "Programming Language :: Python :: 3.7",
+  "Programming Language :: Python :: 3.8",
+  "Programming Language :: Python :: 3.9",
+  "Programming Language :: Python :: 3.10",
+  "Topic :: Software Development :: Libraries :: Python Modules",
+  "Topic :: Software Development :: Quality Assurance",
+]
+dependencies = [
+  "click>=8.0.0",
+  "mypy_extensions>=0.4.3",
+  "pathspec>=0.9.0",
+  "platformdirs>=2",
+  "tomli>=1.1.0; python_full_version < '3.11.0a7'",
+  "typed-ast>=1.4.2; python_version < '3.8' and implementation_name == 'cpython'",
+  "typing_extensions>=3.10.0.0; python_version < '3.10'",
+]
+dynamic = ["readme", "version"]
+
+[project.optional-dependencies]
+colorama = ["colorama>=0.4.3"]
+uvloop = ["uvloop>=0.15.2"]
+d = [
+  "aiohttp>=3.7.4",
+]
+jupyter = [
+  "ipython>=7.8.0",
+  "tokenize-rt>=3.2.0",
+]
+
+[project.scripts]
+black = "black:patched_main"
+blackd = "blackd:patched_main [d]"
+
+[project.urls]
+Changelog = "https://github.com/psf/black/blob/main/CHANGES.md"
+Homepage = "https://github.com/psf/black"
+
+[tool.hatch.metadata.hooks.fancy-pypi-readme]
+content-type = "text/markdown"
+fragments = [
+  { path = "README.md" },
+  { path = "CHANGES.md" },
+]
+
+[tool.hatch.version]
+source = "vcs"
+
+[tool.hatch.build.hooks.vcs]
+version-file = "src/_black_version.py"
+template = '''
+version = "{version}"
+'''
+
+[tool.hatch.build.targets.sdist]
+exclude = ["/profiling"]
+
+[tool.hatch.build.targets.wheel]
+only-include = ["src"]
+sources = ["src"]
+
+[tool.hatch.build.targets.wheel.hooks.mypyc]
+enable-by-default = false
+dependencies = [
+  "hatch-mypyc>=0.13.0",
+  "mypy==0.971",
+  # Required stubs to be removed when the packages support PEP 561 themselves
+  "types-typed-ast>=1.4.2",
+]
+require-runtime-dependencies = true
+exclude = [
+  # There's no good reason for blackd to be compiled.
+  "/src/blackd",
+  # Not performance sensitive, so save bytes + compilation time:
+  "/src/blib2to3/__init__.py",
+  "/src/blib2to3/pgen2/__init__.py",
+  "/src/black/output.py",
+  "/src/black/concurrency.py",
+  "/src/black/files.py",
+  "/src/black/report.py",
+  # Breaks the test suite when compiled (and is also useless):
+  "/src/black/debug.py",
+  # Compiled modules can't be run directly and that's a problem here:
+  "/src/black/__main__.py",
+]
+options = { debug_level = "0" }
 
 [tool.cibuildwheel]
 build-verbosity = 1
 # So these are the environments we target:
-# - Python: CPython 3.6+ only
+# - Python: CPython 3.7+ only
 # - Architecture (64-bit only): amd64 / x86_64, universal2, and arm64
 # - OS: Linux (no musl), Windows, and macOS
 build = "cp3*-*"
 skip = ["*-manylinux_i686", "*-musllinux_*", "*-win32", "pp-*"]
-before-build = ["pip install -r .github/mypyc-requirements.txt"]
 # This is the bare minimum needed to run the test suite. Pulling in the full
 # test_requirements.txt would download a bunch of other packages not necessary
 # here and would slow down the testing step a fair bit.
@@ -49,7 +159,7 @@ test-extras = ["d"," jupyter"]
 test-skip = ["*-macosx_arm64", "*-macosx_universal2:arm64"]
 
 [tool.cibuildwheel.environment]
-BLACK_USE_MYPYC = "1"
+HATCH_BUILD_HOOKS_ENABLE = "1"
 MYPYC_OPT_LEVEL = "3"
 MYPYC_DEBUG_LEVEL = "0"
 # The dependencies required to build wheels with mypyc aren't specified in
@@ -61,28 +171,17 @@ AIOHTTP_NO_EXTENSIONS = "1"
 
 [tool.cibuildwheel.linux]
 before-build = [
-    "pip install -r .github/mypyc-requirements.txt",
     "yum install -y clang gcc",
 ]
 
 [tool.cibuildwheel.linux.environment]
-BLACK_USE_MYPYC = "1"
+HATCH_BUILD_HOOKS_ENABLE = "1"
 MYPYC_OPT_LEVEL = "3"
 MYPYC_DEBUG_LEVEL = "0"
-PIP_NO_BUILD_ISOLATION = "no"
 # Black needs Clang to compile successfully on Linux.
 CC = "clang"
 AIOHTTP_NO_EXTENSIONS = "1"
 
-[tool.cibuildwheel.windows]
-# For some reason, (compiled) mypyc is failing to start up with "ImportError: DLL load
-# failed: A dynamic link library (DLL) initialization routine failed." on Windows for
-# at least 3.6. Let's just use interpreted mypy[c].
-# See also: https://github.com/mypyc/mypyc/issues/819.
-before-build = [
-    "pip install -r .github/mypyc-requirements.txt --no-binary mypy"
-]
-
 [tool.isort]
 atomic = true
 profile = "black"