Add integration tests.

Set up integration tests that install packages to temporary
directories.

Change-Id: Iec90838fec961228fca24c0decc088de55303350

--HG--
extra : rebase_source : f5219f8411db4b79694a74659e22b0c0b1c771ab

setuptools/tests/test_integration.py

+"""Run some integration tests.
+
+Try to install a few packages.
+"""
+
+import glob
+import os
+import shutil
+import site
+import sys
+import tempfile
+import unittest
+
+import pytest
+
+from setuptools.command.easy_install import easy_install
+from setuptools.command import easy_install as easy_install_pkg
+from setuptools.dist import Distribution
+
+
+@pytest.fixture
+def install_context(request):
+    """Fixture to set up temporary installation directory.
+    """
+    # Save old values so we can restore them.
+    new_cwd = tempfile.mkdtemp()
+    old_cwd = os.getcwd()
+    old_enable_site = site.ENABLE_USER_SITE
+    old_file = easy_install_pkg.__file__
+    old_base = site.USER_BASE
+    old_site = site.USER_SITE
+    old_ppath = os.environ.get('PYTHONPATH')
+
+    def fin():
+        os.chdir(old_cwd)
+        shutil.rmtree(new_cwd)
+        shutil.rmtree(site.USER_BASE)
+        shutil.rmtree(site.USER_SITE)
+        site.USER_BASE = old_base
+        site.USER_SITE = old_site
+        site.ENABLE_USER_SITE = old_enable_site
+        easy_install_pkg.__file__ = old_file
+        os.environ['PYTHONPATH'] = old_ppath or ''
+    request.addfinalizer(fin)
+
+    # Change the environment and site settings to control where the
+    # files are installed and ensure we do not overwrite anything.
+    site.USER_BASE = tempfile.mkdtemp()
+    site.USER_SITE = tempfile.mkdtemp()
+    easy_install_pkg.__file__ = site.USER_SITE
+    os.chdir(new_cwd)
+    install_dir = tempfile.mkdtemp()
+    sys.path.append(install_dir)
+    os.environ['PYTHONPATH'] = os.path.pathsep.join(sys.path)
+
+    # Set up the command for performing the installation.
+    values = {}
+    dist = Distribution()
+    cmd = easy_install(dist)
+    cmd.install_dir = install_dir
+    return cmd
+
+
+def _install_one(requirement, cmd, pkgname, modulename):
+    cmd.args = [requirement]
+    cmd.ensure_finalized()
+    cmd.run()
+    target = cmd.install_dir
+    dest_path = glob.glob(os.path.join(target, pkgname + '*.egg'))
+    assert dest_path
+    assert os.path.exists(os.path.join(dest_path[0], pkgname, modulename))
+
+def test_stevedore(install_context):
+    _install_one('stevedore', install_context,
+                 'stevedore', 'extension.py')
+
+# def test_virtualenvwrapper(install_context):
+#     _install_one('virtualenvwrapper', install_context,
+#                  'virtualenvwrapper', 'hook_loader.py')
+
+# def test_pbr(install_context):
+#     _install_one('pbr', install_context,
+#                  'pbr', 'core.py')
+
+# def test_python_novaclient(install_context):
+#     _install_one('python-novaclient', install_context,
+#                  'novaclient', 'base.py')