setup.py: go back to making an universal wheel [GH-1]

Author: Sarcasm

.travis.yml

@@ -18,9 +18,7 @@ matrix:
     - python: 3.6
       env: TOXENV=lint,docs
     - python: 3.6
-      # requirements.txt installs compdb and its dependencies,
-      # the ZSH script depends on compdb
-      install: pip install -r requirements.txt
+      install: python setup.py install
       script: ./contrib/zsh/check-all-helps
 
 install: pip install tox wheel

requirements.txt

@@ -1,3 +1,2 @@
-# install the 'abstract' dependencies of setup.py
-# -- https://caremad.io/posts/2013/07/setup-vs-requirement/
--e .
+# Note: the use of environment marker requires pip >= 7.1.0
+configparser; python_version < '3.0'

setup.cfg

@@ -0,0 +1,2 @@
+[bdist_wheel]
+universal=1

setup.py

@@ -1,27 +1,54 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
+import setuptools
+import sys
+
 from codecs import open
+from distutils.version import LooseVersion
 from os import path
 from setuptools import setup, find_packages
-import sys
 
 local_path = path.abspath(path.dirname(__file__))
 
+# find_packages()'s 'include' parameter has been introduced in setuptools 3.3.
+#
+# Ubuntu 14:04 comes with 3.3 for the system wide installation,
+# but when using virtualenv the setuptools version is 2.2.
+# The solution is to upgrade setuptools in the virtualenv.
+if LooseVersion(setuptools.__version__) < LooseVersion('3.3'):
+    print("setuptools version:", str(LooseVersion(setuptools.__version__)))
+    print("to upgrade with pip, type: pip install -U setuptools")
+    raise AssertionError("compdb requires setuptools 3.3 higher")
+
 with open(path.join(local_path, 'README.rst'), encoding='utf-8') as f:
     long_desc = f.read()
 
 about = {}
 with open(path.join(local_path, "compdb", "__about__.py")) as f:
     exec(f.read(), about)
 
-dependencies = []
+install_requires = []
+extras_require = {}
 
-if sys.version_info[0] < 3:
-    # Would be nicer in 'extra_require' with an environment marker (PEP 496),
-    # but this requires a more recent version of setuptools
-    # than provided by Ubuntu 14.04.
-    dependencies.append('configparser')
+# Depending on the setuptools version,
+# fill in install_requires or extras_require.
+#
+# The ideas comes from the following article:
+# - https://hynek.me/articles/conditional-python-dependencies/
+#
+# This handles Ubuntu 14.04, which comes with setuptools 3.3.
+# But not everything is handled, a more recent version of setuptools
+# is still required to support bdist_wheel.
+if LooseVersion(setuptools.__version__) < LooseVersion('18'):
+    if "bdist_wheel" in sys.argv:
+        print("setuptools version:", str(LooseVersion(setuptools.__version__)))
+        print("to upgrade with pip, type: pip install -U setuptools")
+        raise AssertionError("setuptools >= 18 required for wheels")
+    if sys.version_info[0] < 3:
+        install_requires.append('configparser')
+else:  # setuptools >= 18
+    extras_require[":python_version<'3.0'"] = ['configparser']
 
 setup(
     name=about['__prog__'],
@@ -55,4 +82,5 @@
         ],
     },
     python_requires='>=2.7,!=3.0.*,!=3.1.*,!=3.2.*',
-    install_requires=dependencies)
+    install_requires=install_requires,
+    extras_require=extras_require)