Depend on gnureadline when building binary wheel or setupext.check_for_readline() fails

This is a follow up to 4d9f6f00a4f0798e41700c22a839eddff0881692 based on
the discussion in pull request  #7047 where we seem to have found a middle
ground that should make everyone happy :-)

setup.py

@@ -1,349 +1,349 b''
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 """Setup script for IPython.
 
 Under Posix environments it works like a typical setup.py script.
 Under Windows, the command sdist is not supported, since IPython
 requires utilities which are not available under Windows."""
 
 #-----------------------------------------------------------------------------
 #  Copyright (c) 2008-2011, IPython Development Team.
 #  Copyright (c) 2001-2007, Fernando Perez <[e-mail]>
 #  Copyright (c) 2001, Janko Hauser <[e-mail]>
 #  Copyright (c) 2001, Nathaniel Gray <[e-mail]>
 #
 #  Distributed under the terms of the Modified BSD License.
 #
 #  The full license is in the file COPYING.rst, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Minimal Python version sanity check
 #-----------------------------------------------------------------------------
 from __future__ import print_function
 
 import sys
 
 # This check is also made in IPython/__init__, don't forget to update both when
 # changing Python version requirements.
 v = sys.version_info
 if v[:2] < (2,7) or (v[0] >= 3 and v[:2] < (3,3)):
     error = "ERROR: IPython requires Python version 2.7 or 3.3 or above."
     print(error, file=sys.stderr)
     sys.exit(1)
 
 PY3 = (sys.version_info[0] >= 3)
 
 # At least we're on the python version we need, move on.
 
 #-------------------------------------------------------------------------------
 # Imports
 #-------------------------------------------------------------------------------
 
 # Stdlib imports
 import os
 import shutil
 
 from glob import glob
 
 # BEFORE importing distutils, remove MANIFEST. distutils doesn't properly
 # update it when the contents of directories change.
 if os.path.exists('MANIFEST'): os.remove('MANIFEST')
 
 from distutils.core import setup
 
 # Our own imports
 from setupbase import target_update
 
 from setupbase import (
     setup_args,
     find_packages,
     find_package_data,
     check_package_data_first,
     find_entry_points,
     build_scripts_entrypt,
     find_data_files,
     check_for_dependencies,
     git_prebuild,
     check_submodule_status,
     update_submodules,
     require_submodules,
     UpdateSubmodules,
     get_bdist_wheel,
     CompileCSS,
     JavascriptVersion,
     css_js_prerelease,
     install_symlinked,
     install_lib_symlink,
     install_scripts_for_symlink,
     unsymlink,
 )
 from setupext import setupext
 
 isfile = os.path.isfile
 pjoin = os.path.join
 
 #-----------------------------------------------------------------------------
 # Function definitions
 #-----------------------------------------------------------------------------
 
 def cleanup():
     """Clean up the junk left around by the build process"""
     if "develop" not in sys.argv and "egg_info" not in sys.argv:
         try:
             shutil.rmtree('ipython.egg-info')
         except:
             try:
                 os.unlink('ipython.egg-info')
             except:
                 pass
 
 #-------------------------------------------------------------------------------
 # Handle OS specific things
 #-------------------------------------------------------------------------------
 
 if os.name in ('nt','dos'):
     os_name = 'windows'
 else:
     os_name = os.name
 
 # Under Windows, 'sdist' has not been supported.  Now that the docs build with
 # Sphinx it might work, but let's not turn it on until someone confirms that it
 # actually works.
 if os_name == 'windows' and 'sdist' in sys.argv:
     print('The sdist command is not available under Windows.  Exiting.')
     sys.exit(1)
 
 #-------------------------------------------------------------------------------
 # Make sure we aren't trying to run without submodules
 #-------------------------------------------------------------------------------
 here = os.path.abspath(os.path.dirname(__file__))
 
 def require_clean_submodules():
     """Check on git submodules before distutils can do anything
 
     Since distutils cannot be trusted to update the tree
     after everything has been set in motion,
     this is not a distutils command.
     """
     # PACKAGERS: Add a return here to skip checks for git submodules
     
     # don't do anything if nothing is actually supposed to happen
     for do_nothing in ('-h', '--help', '--help-commands', 'clean', 'submodule'):
         if do_nothing in sys.argv:
             return
 
     status = check_submodule_status(here)
 
     if status == "missing":
         print("checking out submodules for the first time")
         update_submodules(here)
     elif status == "unclean":
         print('\n'.join([
             "Cannot build / install IPython with unclean submodules",
             "Please update submodules with",
             "    python setup.py submodule",
             "or",
             "    git submodule update",
             "or commit any submodule changes you have made."
         ]))
         sys.exit(1)
 
 require_clean_submodules()
 
 #-------------------------------------------------------------------------------
 # Things related to the IPython documentation
 #-------------------------------------------------------------------------------
 
 # update the manuals when building a source dist
 if len(sys.argv) >= 2 and sys.argv[1] in ('sdist','bdist_rpm'):
 
     # List of things to be updated. Each entry is a triplet of args for
     # target_update()
     to_update = [
                   # FIXME - Disabled for now: we need to redo an automatic way
                   # of generating the magic info inside the rst.
                   #('docs/magic.tex',
                   #['IPython/Magic.py'],
                   #"cd doc && ./update_magic.sh" ),
 
                  ('docs/man/ipcluster.1.gz',
                   ['docs/man/ipcluster.1'],
                   'cd docs/man && gzip -9c ipcluster.1 > ipcluster.1.gz'),
 
                  ('docs/man/ipcontroller.1.gz',
                   ['docs/man/ipcontroller.1'],
                   'cd docs/man && gzip -9c ipcontroller.1 > ipcontroller.1.gz'),
 
                  ('docs/man/ipengine.1.gz',
                   ['docs/man/ipengine.1'],
                   'cd docs/man && gzip -9c ipengine.1 > ipengine.1.gz'),
 
                  ('docs/man/ipython.1.gz',
                   ['docs/man/ipython.1'],
                   'cd docs/man && gzip -9c ipython.1 > ipython.1.gz'),
 
                  ]
 
 
     [ target_update(*t) for t in to_update ]
 
 #---------------------------------------------------------------------------
 # Find all the packages, package data, and data_files
 #---------------------------------------------------------------------------
 
 packages = find_packages()
 package_data = find_package_data()
 
 data_files = find_data_files()
 
 setup_args['packages'] = packages
 setup_args['package_data'] = package_data
 setup_args['data_files'] = data_files
 
 #---------------------------------------------------------------------------
 # custom distutils commands
 #---------------------------------------------------------------------------
 # imports here, so they are after setuptools import if there was one
 from distutils.command.sdist import sdist
 from distutils.command.upload import upload
 
 class UploadWindowsInstallers(upload):
 
     description = "Upload Windows installers to PyPI (only used from tools/release_windows.py)"
     user_options = upload.user_options + [
         ('files=', 'f', 'exe file (or glob) to upload')
     ]
     def initialize_options(self):
         upload.initialize_options(self)
         meta = self.distribution.metadata
         base = '{name}-{version}'.format(
             name=meta.get_name(),
             version=meta.get_version()
         )
         self.files = os.path.join('dist', '%s.*.exe' % base)
 
     def run(self):
         for dist_file in glob(self.files):
             self.upload_file('bdist_wininst', 'any', dist_file)
 
 setup_args['cmdclass'] = {
     'build_py': css_js_prerelease(
             check_package_data_first(git_prebuild('IPython')),
         strict=False),
     'sdist' : css_js_prerelease(git_prebuild('IPython', sdist)),
     'upload_wininst' : UploadWindowsInstallers,
     'submodule' : UpdateSubmodules,
     'css' : CompileCSS,
     'symlink': install_symlinked,
     'install_lib_symlink': install_lib_symlink,
     'install_scripts_sym': install_scripts_for_symlink,
     'unsymlink': unsymlink,
     'jsversion' : JavascriptVersion,
 }
 
 #---------------------------------------------------------------------------
 # Handle scripts, dependencies, and setuptools specific things
 #---------------------------------------------------------------------------
 
 # For some commands, use setuptools.  Note that we do NOT list install here!
 # If you want a setuptools-enhanced install, just run 'setupegg.py install'
 needs_setuptools = set(('develop', 'release', 'bdist_egg', 'bdist_rpm',
            'bdist', 'bdist_dumb', 'bdist_wininst', 'bdist_wheel',
            'egg_info', 'easy_install', 'upload', 'install_egg_info',
             ))
 
 if len(needs_setuptools.intersection(sys.argv)) > 0:
     import setuptools
 
 # This dict is used for passing extra arguments that are setuptools
 # specific to setup
 setuptools_extra_args = {}
 
 # setuptools requirements
 
 extras_require = dict(
     parallel = ['pyzmq>=2.1.11'],
     qtconsole = ['pyzmq>=2.1.11', 'pygments'],
     zmq = ['pyzmq>=2.1.11'],
     doc = ['Sphinx>=1.1', 'numpydoc'],
     test = ['nose>=0.10.1', 'requests'],
     terminal = [],
     nbformat = ['jsonschema>=2.0'],
     notebook = ['tornado>=4.0', 'pyzmq>=2.1.11', 'jinja2', 'pygments', 'mistune>=0.3.1'],
     nbconvert = ['pygments', 'jinja2', 'mistune>=0.3.1']
 )
 
 if sys.version_info < (3, 3):
     extras_require['test'].append('mock')
 
 extras_require['notebook'].extend(extras_require['nbformat'])
 extras_require['nbconvert'].extend(extras_require['nbformat'])
 
 everything = set()
 for deps in extras_require.values():
     everything.update(deps)
 extras_require['all'] = everything
 
 install_requires = []
 
 # add readline
 if sys.platform == 'darwin':
-    if not setupext.check_for_readline():
+    if 'bdist_wheel' in sys.argv[1:] or not setupext.check_for_readline():
         install_requires.append('gnureadline')
 elif sys.platform.startswith('win'):
     extras_require['terminal'].append('pyreadline>=2.0')
 
 
 if 'setuptools' in sys.modules:
     # setup.py develop should check for submodules
     from setuptools.command.develop import develop
     setup_args['cmdclass']['develop'] = require_submodules(develop)
     setup_args['cmdclass']['bdist_wheel'] = css_js_prerelease(get_bdist_wheel())
     
     setuptools_extra_args['zip_safe'] = False
     setuptools_extra_args['entry_points'] = {'console_scripts':find_entry_points()}
     setup_args['extras_require'] = extras_require
     requires = setup_args['install_requires'] = install_requires
 
     # Script to be run by the windows binary installer after the default setup
     # routine, to add shortcuts and similar windows-only things.  Windows
     # post-install scripts MUST reside in the scripts/ dir, otherwise distutils
     # doesn't find them.
     if 'bdist_wininst' in sys.argv:
         if len(sys.argv) > 2 and \
                ('sdist' in sys.argv or 'bdist_rpm' in sys.argv):
             print >> sys.stderr, "ERROR: bdist_wininst must be run alone. Exiting."
             sys.exit(1)
         setup_args['data_files'].append(
             ['Scripts', ('scripts/ipython.ico', 'scripts/ipython_nb.ico')])
         setup_args['scripts'] = [pjoin('scripts','ipython_win_post_install.py')]
         setup_args['options'] = {"bdist_wininst":
                                  {"install_script":
                                   "ipython_win_post_install.py"}}
 
 else:
     # If we are installing without setuptools, call this function which will
     # check for dependencies an inform the user what is needed.  This is
     # just to make life easy for users.
     for install_cmd in ('install', 'symlink'):
         if install_cmd in sys.argv:
             check_for_dependencies()
             break
     # scripts has to be a non-empty list, or install_scripts isn't called
     setup_args['scripts'] = [e.split('=')[0].strip() for e in find_entry_points()]
 
     setup_args['cmdclass']['build_scripts'] = build_scripts_entrypt
 
 #---------------------------------------------------------------------------
 # Do the actual setup now
 #---------------------------------------------------------------------------
 
 setup_args.update(setuptools_extra_args)
 
 def main():
     setup(**setup_args)
     cleanup()
 
 if __name__ == '__main__':
     main()