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

5 files changed, 117 insertions, 67 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index 960e5d9b..7a9ed446 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -3,6 +3,15 @@ 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
 ---
 
diff --git a/setuptools.egg-info/entry_points.txt b/setuptools.egg-info/entry_points.txt
index 0253d11a..560a7041 100644
--- a/setuptools.egg-info/entry_points.txt
+++ b/setuptools.egg-info/entry_points.txt
@@ -1,62 +1,62 @@
-[setuptools.installation]
-eggsecutable = setuptools.command.easy_install:bootstrap
-
-[distutils.setup_keywords]
-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
-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
-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
-
-[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
-install_scripts = setuptools.command.install_scripts:install_scripts
-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
-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
-develop = setuptools.command.develop:develop
-install_egg_info = setuptools.command.install_egg_info:install_egg_info
-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
-
+[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

+use_2to3_exclude_fixers = setuptools.dist:assert_string_list

+convert_2to3_doctests = setuptools.dist:assert_string_list

+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

+tests_require = setuptools.dist:check_requirements

+package_data = setuptools.dist:check_package_data

+test_suite = setuptools.dist:check_test_suite

+include_package_data = setuptools.dist:assert_bool

+install_requires = setuptools.dist:check_requirements

+

+[distutils.commands]

+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

+bdist_egg = setuptools.command.bdist_egg:bdist_egg

+test = setuptools.command.test:test

+install_egg_info = setuptools.command.install_egg_info:install_egg_info

+install_lib = setuptools.command.install_lib:install_lib

+sdist = setuptools.command.sdist:sdist

+register = setuptools.command.register:register

+develop = setuptools.command.develop:develop

+build_py = setuptools.command.build_py:build_py

+setopt = setuptools.command.setopt:setopt

+build_ext = setuptools.command.build_ext:build_ext

+alias = setuptools.command.alias:alias

+easy_install = setuptools.command.easy_install:easy_install

+bdist_wininst = setuptools.command.bdist_wininst:bdist_wininst

+

diff --git a/setuptools.egg-info/requires.txt b/setuptools.egg-info/requires.txt
index e5db30ad..a49a923e 100644
--- a/setuptools.egg-info/requires.txt
+++ b/setuptools.egg-info/requires.txt
@@ -1,7 +1,7 @@
 
 
-[ssl:sys_platform=='win32']
-wincertstore==0.2
-
 [certs]
-certifi==1.0.1
\ No newline at end of file
+certifi==1.0.1
+
+[ssl:sys_platform=='win32']
+wincertstore==0.2
\ No newline at end of file
diff --git a/setuptools/__init__.py b/setuptools/__init__.py
index a96e4c9d..86afab63 100644
--- a/setuptools/__init__.py
+++ b/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
diff --git a/setuptools/tests/test_find_packages.py b/setuptools/tests/test_find_packages.py
index c50309d2..abb0dd61 100644
--- a/setuptools/tests/test_find_packages.py
+++ b/setuptools/tests/test_find_packages.py
@@ -1,12 +1,16 @@
 """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'])