Switch to setuptools declarative syntax through setup.cfg

Avoids mixing code and configuration. This approach can allow for some
automation and also reduces boilerplate in setup.py.

Available since setuptools 30.3.0 (Dec 8, 2016).

https://setuptools.readthedocs.io/en/latest/setuptools.html#configuring-setup-using-setup-cfg-files

setup.cfg

@@ -1,3 +1,54 @@
+[metadata]
+name = pip-tools
+url = https://github.com/jazzband/pip-tools/
+license = BSD
+author = Vincent Driessen
+author_email = me@nvie.com
+description = pip-tools keeps your pinned dependencies fresh.
+long_description = file: README.rst
+classifiers =
+    Development Status :: 5 - Production/Stable
+    Intended Audience :: Developers
+    Intended Audience :: System Administrators
+    License :: OSI Approved :: BSD License
+    Operating System :: OS Independent
+    Programming Language :: Python
+    Programming Language :: Python :: 2
+    Programming Language :: Python :: 2.7
+    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
+    Programming Language :: Python :: Implementation :: CPython
+    Programming Language :: Python :: Implementation :: PyPy
+    Topic :: System :: Systems Administration
+
+[options]
+python_requires = >=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*
+setup_requires = setuptools_scm
+packages = find:
+zip_safe = false
+install_requires =
+    click >= 7
+    six
+    pip >= 20.0
+
+[options.packages.find]
+exclude = tests
+
+[options.extras_require]
+testing =
+    mock
+    pytest
+    pytest-rerunfailures
+coverage = pytest-cov
+
+[options.entry_points]
+console_scripts =
+    pip-compile = piptools.scripts.compile:cli
+    pip-sync = piptools.scripts.sync:cli
+
 [bdist_wheel]
 universal = 1
 

setup.py

@@ -1,60 +1,3 @@
-"""
-pip-tools keeps your pinned dependencies fresh.
-"""
-from os.path import abspath, dirname, join
+from setuptools import setup
 
-from setuptools import find_packages, setup
-
-
-def read_file(filename):
-    """Read the contents of a file located relative to setup.py"""
-    with open(join(abspath(dirname(__file__)), filename)) as thefile:
-        return thefile.read()
-
-
-setup(
-    name="pip-tools",
-    use_scm_version=True,
-    url="https://github.com/jazzband/pip-tools/",
-    license="BSD",
-    author="Vincent Driessen",
-    author_email="me@nvie.com",
-    description=__doc__.strip(),
-    long_description=read_file("README.rst"),
-    long_description_content_type="text/x-rst",
-    packages=find_packages(exclude=["tests"]),
-    package_data={},
-    python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*",
-    setup_requires=["setuptools_scm"],
-    install_requires=["click>=7", "six", "pip>=20.0"],
-    extras_require={
-        "testing": ["mock", "pytest", "pytest-rerunfailures"],
-        "coverage": ["pytest-cov"],
-    },
-    zip_safe=False,
-    entry_points={
-        "console_scripts": [
-            "pip-compile = piptools.scripts.compile:cli",
-            "pip-sync = piptools.scripts.sync:cli",
-        ]
-    },
-    platforms="any",
-    classifiers=[
-        "Development Status :: 5 - Production/Stable",
-        "Intended Audience :: Developers",
-        "Intended Audience :: System Administrators",
-        "License :: OSI Approved :: BSD License",
-        "Operating System :: OS Independent",
-        "Programming Language :: Python",
-        "Programming Language :: Python :: 2",
-        "Programming Language :: Python :: 2.7",
-        "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.5",
-        "Programming Language :: Python :: 3.6",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
-        "Programming Language :: Python :: Implementation :: CPython",
-        "Programming Language :: Python :: Implementation :: PyPy",
-        "Topic :: System :: Systems Administration",
-    ],
-)
+setup(use_scm_version=True)