Revert "move back to setuptools (#367)"

docs/conf.py

@@ -41,11 +41,11 @@
 
 base_dir = os.path.join(os.path.dirname(__file__), os.pardir)
 about = {}
-with open(os.path.join(base_dir, "packaging", "__about__.py")) as f:
+with open(os.path.join(base_dir, "packaging", "__init__.py")) as f:
     exec(f.read(), about)
 
 version = release = about["__version__"]
-copyright = about["__copyright__"]
+copyright = "2014-2019 Donald Stufft and individual contributors"
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.

packaging/__init__.py

@@ -1,25 +1,5 @@
 # This file is dual licensed under the terms of the Apache License, Version
 # 2.0, and the BSD License. See the LICENSE file in the root of this repository
 # for complete details.
-
-from .__about__ import (
-    __author__,
-    __copyright__,
-    __email__,
-    __license__,
-    __summary__,
-    __title__,
-    __uri__,
-    __version__,
-)
-
-__all__ = [
-    "__title__",
-    "__summary__",
-    "__uri__",
-    "__version__",
-    "__author__",
-    "__email__",
-    "__license__",
-    "__copyright__",
-]
+"""Core utilities for Python packages"""
+__version__ = "21.4.dev0"

pyproject.toml

@@ -1,3 +1,34 @@
 [build-system]
-requires = ['setuptools >= 40.8.0', 'wheel']
-build-backend = 'setuptools.build_meta'
+requires = ["flit_core >=2,<4"]
+build-backend = "flit_core.buildapi"
+
+[tool.flit.metadata]
+module = "packaging"
+author = "Donald Stufft and individual contributors"
+author-email = "donald@stufft.io"
+home-page = "https://github.com/pypa/packaging"
+description-file = "README.rst"
+classifiers = [
+        "Development Status :: 5 - Production/Stable",
+        "Intended Audience :: Developers",
+        "License :: OSI Approved :: Apache Software License",
+        "License :: OSI Approved :: BSD License",
+        "Programming Language :: Python",
+        "Programming Language :: Python :: 3",
+        "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",
+        "Programming Language :: Python :: Implementation :: CPython",
+        "Programming Language :: Python :: Implementation :: PyPy",
+]
+requires-python = ">=3.7"
+requires = ["pyparsing>=2.0.2,!=3.0.5"] # 2.0.2 + needed to avoid issue #91
+
+[tool.flit.metadata.urls]
+Documentation = "https://packaging.pypa.io/"
+Changelog = "https://packaging.pypa.io/en/latest/changelog.html"
+
+[tool.flit.sdist]
+include = ["LICENSE", "LICENSE.BSD", "LICENSE.APACHE"]