Merge pull request #428 from buildout/reinout-wheel-via-setuptools

Install wheels via setuptools, fixes #425

CHANGES.rst

@@ -4,7 +4,16 @@ Change History
 2.9.7 (unreleased)
 ==================
 
-- Nothing changed yet.
+- Setuptools 38.2.0 started supporting wheels. Through setuptools, buildout
+  now also supports wheels! You need at least version 38.2.3 to get proper
+  namespace support.
+
+  This setuptools change interfered with buildout's recent support for
+  `buildout.wheel <https://github.com/buildout/buildout.wheel>`_, resulting in
+  a sudden "Wheels are not supported" error message (see `issue 435
+  <https://github.com/buildout/buildout/issues/425>`_). Fixed by making
+  setuptools the default, though you can still use the buildout.wheel if you
+  want.
 
 
 2.9.6 (2017-12-01)

src/zc/buildout/easy_install.py

@@ -37,6 +37,16 @@ import tempfile
 import zc.buildout
 import warnings
 
+try:
+    from setuptools.wheel import Wheel  # This is the important import
+    from setuptools import __version__ as setuptools_version
+    # Now we need to check if we have at least 38.2.3 for namespace support.
+    SETUPTOOLS_SUPPORTS_WHEELS = (
+        pkg_resources.SetuptoolsVersion(setuptools_version) >=
+        pkg_resources.SetuptoolsVersion('38.2.3'))
+except ImportError:
+    SETUPTOOLS_SUPPORTS_WHEELS = False
+
 warnings.filterwarnings(
     'ignore', '.+is being parsed as a legacy, non PEP 440, version')
 
@@ -83,9 +93,6 @@ setuptools_path = buildout_and_setuptools_path
 FILE_SCHEME = re.compile('file://', re.I).match
 DUNDER_FILE_PATTERN = re.compile(r"__file__ = '(?P<filename>.+)'$")
 
-def wheel_to_egg(dist, dest):
-    raise zc.buildout.UserError("Wheels are not supported")
-
 class _Monkey(object):
     def __init__(self, module, **kw):
         mdict = self._mdict = module.__dict__
@@ -1619,25 +1626,19 @@ def unpack_egg(location, dest):
     setuptools.archive_util.unpack_archive(location, dest)
 
 
-WHEEL_TO_EGG_WARNING = """
-Using unpack_wheel() shim over the deprecated wheel_to_egg() hook.
-Please update your wheel extension implementation for one that installs a .whl
-handler in %s.UNPACKERS
-""".strip() % (__name__,)
+WHEEL_WARNING = """
+*.whl file detected (%s), you'll need setuptools >= 38.2.3 for that
+or an extension like buildout.wheel > 0.2.0.
+"""
+
 
 def unpack_wheel(location, dest):
-    # Deprecated backward compatibility shim. Please do not use.
-    logger.warning(WHEEL_TO_EGG_WARNING)
-    basename = os.path.basename(location)
-    dists = setuptools.package_index.distros_for_location(location, basename)
-    # `wheel_to_egg()` might generate zipped eggs, so we have to make sure we
-    # get unpacked eggs in the end:
-    tmp_dest = tempfile.mkdtemp(dir=dest)
-    wheel_to_egg(list(dists)[0], tmp_dest)
-    [egg] = glob.glob(os.path.join(tmp_dest, '*.egg'))
-    unpack_egg(egg, dest)
-    shutil.rmtree(tmp_dest)
-    
+    if SETUPTOOLS_SUPPORTS_WHEELS:
+        wheel = Wheel(location)
+        wheel.install_as_egg(os.path.join(dest, wheel.egg_name()))
+    else:
+        raise zc.buildout.UserError(WHEEL_WARNING % location)
+
 
 UNPACKERS = {
     '.egg': unpack_egg,

src/zc/buildout/tests.py

@@ -3144,52 +3144,6 @@ def test_buildout_doesnt_keep_adding_itself_to_versions():
 if sys.platform == 'win32':
     del buildout_honors_umask # umask on dohs is academic
 
-class UnitTests(unittest.TestCase):
-
-    @property
-    def globs(self):
-        return self.__dict__
-
-    def setUp(self):
-        easy_install_SetUp(self)
-        import setuptools.package_index
-        setuptools.package_index.EXTENSIONS.append('.whl')
-        import zc.buildout.easy_install
-        self.orig_wheel_to_egg = zc.buildout.easy_install.wheel_to_egg
-
-    def tearDown(self):
-        import zc.buildout.easy_install
-        zc.buildout.testing.buildoutTearDown(self)
-        import setuptools.package_index
-        setuptools.package_index.EXTENSIONS.remove('.whl')
-        zc.buildout.easy_install.wheel_to_egg = self.orig_wheel_to_egg
-
-    def test_wheel_to_egg(self):
-        [egg_name] = [n for n in os.listdir(self.sample_eggs)
-                  if n.startswith('demo-0.3-')]
-        path = os.path.join(self.sample_eggs, egg_name)
-        os.rename(path, os.path.join(self.sample_eggs, 'demo-0.3.whl'))
-
-        import zc.buildout.easy_install
-        installer = zc.buildout.easy_install.Installer(
-            os.path.join(self.sample_buildout, 'eggs'),
-            index = self.sample_eggs)
-
-        # Can't install because the original hook is in place:
-        with self.assertRaises(zc.buildout.UserError):
-            installer.install(['demo'])
-
-        def wheel_to_egg(dist, dest):
-            newloc = os.path.join(dest, egg_name)
-            shutil.copy(dist.location, newloc)
-            return pkg_resources.Distribution.from_filename(newloc)
-        zc.buildout.easy_install.wheel_to_egg = wheel_to_egg
-        egg_dir = os.path.join(self.sample_buildout, 'eggs')
-        self.assertFalse(egg_name in os.listdir(egg_dir))
-        installer.install(['demo'])
-        self.assertTrue(egg_name in os.listdir(egg_dir))
-
-
 ######################################################################
 
 def create_sample_eggs(test, executable=sys.executable):
@@ -3769,7 +3723,6 @@ def test_suite():
                ])
             ),
         doctest.DocFileSuite('testing_bugfix.txt'),
-        unittest.makeSuite(UnitTests),
     ]
 
     docdir = os.path.join(ancestor(__file__, 4), 'doc')