Add support for PEP 420 namespace packages to find_packages()

On Python 3.3+, `find_packages()` now considers any subdirectory of the
start directory that's not a regular package (i.e., that doesn't have an
`__init__.py`) to be a namespace package.

The other way this supports PEP 420 is by making sure `__pycache__`
directories are never added to the list of packages.

Fixes issue #97

CHANGES.txt

@@ -2,6 +2,15 @@
 CHANGES
 =======
 
+---
+4.0
+---
+
+* Issue #97: ``find_packages()`` now supports PEP 420 namespace packages. It
+  does so by considering all subdirectories of the start directory that
+  aren't regular packages to be PEP 420 namespace packages (on Python 3.3+
+  only).
+
 ---
 3.3
 ---

setuptools.egg-info/entry_points.txt

 [setuptools.installation]
 eggsecutable = setuptools.command.easy_install:bootstrap
 
+[egg_info.writers]
+entry_points.txt = setuptools.command.egg_info:write_entries
+dependency_links.txt = setuptools.command.egg_info:overwrite_arg
+eager_resources.txt = setuptools.command.egg_info:overwrite_arg
+top_level.txt = setuptools.command.egg_info:write_toplevel_names
+namespace_packages.txt = setuptools.command.egg_info:overwrite_arg
+depends.txt = setuptools.command.egg_info:warn_depends_obsolete
+requires.txt = setuptools.command.egg_info:write_requirements
+PKG-INFO = setuptools.command.egg_info:write_pkg_info
+
+[setuptools.file_finders]
+svn_cvs = setuptools.command.sdist:_default_revctrl
+
+[console_scripts]
+easy_install-3.4 = setuptools.command.easy_install:main
+easy_install = setuptools.command.easy_install:main
+
 [distutils.setup_keywords]
+use_2to3_fixers = setuptools.dist:assert_string_list
+dependency_links = setuptools.dist:assert_string_list
 packages = setuptools.dist:check_packages
-entry_points = setuptools.dist:check_entry_points
-test_suite = setuptools.dist:check_test_suite
-include_package_data = setuptools.dist:assert_bool
-exclude_package_data = setuptools.dist:check_package_data
+use_2to3_exclude_fixers = setuptools.dist:assert_string_list
 convert_2to3_doctests = setuptools.dist:assert_string_list
-extras_require = setuptools.dist:check_extras
-install_requires = setuptools.dist:check_requirements
-use_2to3_fixers = setuptools.dist:assert_string_list
-zip_safe = setuptools.dist:assert_bool
-namespace_packages = setuptools.dist:check_nsp
-test_loader = setuptools.dist:check_importable
 use_2to3 = setuptools.dist:assert_bool
+exclude_package_data = setuptools.dist:check_package_data
+entry_points = setuptools.dist:check_entry_points
+test_loader = setuptools.dist:check_importable
+namespace_packages = setuptools.dist:check_nsp
+zip_safe = setuptools.dist:assert_bool
+extras_require = setuptools.dist:check_extras
 eager_resources = setuptools.dist:assert_string_list
-dependency_links = setuptools.dist:assert_string_list
 tests_require = setuptools.dist:check_requirements
 package_data = setuptools.dist:check_package_data
-use_2to3_exclude_fixers = setuptools.dist:assert_string_list
-
-[setuptools.file_finders]
-svn_cvs = setuptools.command.sdist:_default_revctrl
+test_suite = setuptools.dist:check_test_suite
+include_package_data = setuptools.dist:assert_bool
+install_requires = setuptools.dist:check_requirements
 
 [distutils.commands]
-setopt = setuptools.command.setopt:setopt
-easy_install = setuptools.command.easy_install:easy_install
-bdist_wininst = setuptools.command.bdist_wininst:bdist_wininst
-register = setuptools.command.register:register
-test = setuptools.command.test:test
+upload_docs = setuptools.command.upload_docs:upload_docs
+egg_info = setuptools.command.egg_info:egg_info
 install_scripts = setuptools.command.install_scripts:install_scripts
+saveopts = setuptools.command.saveopts:saveopts
+bdist_rpm = setuptools.command.bdist_rpm:bdist_rpm
+rotate = setuptools.command.rotate:rotate
 install = setuptools.command.install:install
-alias = setuptools.command.alias:alias
 bdist_egg = setuptools.command.bdist_egg:bdist_egg
-build_py = setuptools.command.build_py:build_py
+test = setuptools.command.test:test
+install_egg_info = setuptools.command.install_egg_info:install_egg_info
 install_lib = setuptools.command.install_lib:install_lib
-rotate = setuptools.command.rotate:rotate
-bdist_rpm = setuptools.command.bdist_rpm:bdist_rpm
-egg_info = setuptools.command.egg_info:egg_info
+sdist = setuptools.command.sdist:sdist
+register = setuptools.command.register:register
 develop = setuptools.command.develop:develop
-install_egg_info = setuptools.command.install_egg_info:install_egg_info
+build_py = setuptools.command.build_py:build_py
+setopt = setuptools.command.setopt:setopt
 build_ext = setuptools.command.build_ext:build_ext
-sdist = setuptools.command.sdist:sdist
-saveopts = setuptools.command.saveopts:saveopts
-upload_docs = setuptools.command.upload_docs:upload_docs
-
-[egg_info.writers]
-namespace_packages.txt = setuptools.command.egg_info:overwrite_arg
-eager_resources.txt = setuptools.command.egg_info:overwrite_arg
-entry_points.txt = setuptools.command.egg_info:write_entries
-PKG-INFO = setuptools.command.egg_info:write_pkg_info
-depends.txt = setuptools.command.egg_info:warn_depends_obsolete
-dependency_links.txt = setuptools.command.egg_info:overwrite_arg
-top_level.txt = setuptools.command.egg_info:write_toplevel_names
-requires.txt = setuptools.command.egg_info:write_requirements
-
-[console_scripts]
-easy_install = setuptools.command.easy_install:main
-easy_install-3.4 = setuptools.command.easy_install:main
+alias = setuptools.command.alias:alias
+easy_install = setuptools.command.easy_install:easy_install
+bdist_wininst = setuptools.command.bdist_wininst:bdist_wininst
 

setuptools.egg-info/requires.txt

 
 
-[ssl:sys_platform=='win32']
-wincertstore==0.2
-
 [certs]
 certifi==1.0.1
+
+[ssl:sys_platform=='win32']
+wincertstore==0.2
\ No newline at end of file

setuptools/__init__.py

@@ -56,7 +56,10 @@ def find_packages(where='.', exclude=(), include=()):
             looks_like_package = (
                 '.' not in name
                 and os.path.isdir(fn)
-                and os.path.isfile(os.path.join(fn, '__init__.py'))
+                and (
+                    os.path.isfile(os.path.join(fn, '__init__.py'))
+                    or sys.version_info[:2] >= (3, 3)  # PEP 420
+                )
             )
             if looks_like_package:
                 pkg_name = prefix + name

setuptools/tests/test_find_packages.py

 """Tests for setuptools.find_packages()."""
 import os
 import shutil
+import sys
 import tempfile
 import unittest
 
 from setuptools import find_packages
 
 
+PEP420 = sys.version_info[:2] >= (3, 3)
+
+
 class TestFindPackages(unittest.TestCase):
 
     def setUp(self):
@@ -58,6 +62,7 @@ class TestFindPackages(unittest.TestCase):
         fp.close()
         return path
 
+    @unittest.skipIf(PEP420, 'Not a PEP 420 env')
     def test_regular_package(self):
         self._touch('__init__.py', self.pkg_dir)
         packages = find_packages(self.dist_dir)
@@ -80,3 +85,36 @@ class TestFindPackages(unittest.TestCase):
         self._touch('file.dat', data_dir)
         packages = find_packages(self.dist_dir)
         self.assertTrue('pkg.some.data' not in packages)
+
+    @unittest.skipIf(not PEP420, 'PEP 420 only')
+    def test_pep420_ns_package(self):
+        packages = find_packages(
+            self.dist_dir, include=['pkg*'], exclude=['pkg.subpkg.assets'])
+        self.assertEqual(packages, ['pkg', 'pkg.nspkg', 'pkg.subpkg'])
+
+    @unittest.skipIf(not PEP420, 'PEP 420 only')
+    def test_pep420_ns_package_no_includes(self):
+        packages = find_packages(
+            self.dist_dir, exclude=['pkg.subpkg.assets'])
+        self.assertEqual(packages, ['docs', 'pkg', 'pkg.nspkg', 'pkg.subpkg'])
+
+    @unittest.skipIf(not PEP420, 'PEP 420 only')
+    def test_pep420_ns_package_no_includes_or_excludes(self):
+        packages = find_packages(self.dist_dir)
+        expected = [
+            'docs', 'pkg', 'pkg.nspkg', 'pkg.subpkg', 'pkg.subpkg.assets']
+        self.assertEqual(packages, expected)
+
+    @unittest.skipIf(not PEP420, 'PEP 420 only')
+    def test_regular_package_with_nested_pep420_ns_packages(self):
+        self._touch('__init__.py', self.pkg_dir)
+        packages = find_packages(
+            self.dist_dir, exclude=['docs', 'pkg.subpkg.assets'])
+        self.assertEqual(packages, ['pkg', 'pkg.nspkg', 'pkg.subpkg'])
+
+    @unittest.skipIf(not PEP420, 'PEP 420 only')
+    def test_pep420_ns_package_no_non_package_dirs(self):
+        shutil.rmtree(self.docs_dir)
+        shutil.rmtree(os.path.join(self.dist_dir, 'pkg/subpkg/assets'))
+        packages = find_packages(self.dist_dir)
+        self.assertEqual(packages, ['pkg', 'pkg.nspkg', 'pkg.subpkg'])