From bb36b41818b99079372dbb55b272465820d58de3 Mon Sep 17 00:00:00 2001
From: Paul Ganssle <paul@ganssle.io>
Date: Wed, 11 Jul 2018 09:51:44 -0400
Subject: Add test for cache_path race condition

This mocks out the isdir call so that the directory is created
immediately after you determine whether or not it exists, thus
simulating a race condition between two threads or processes
creating the same directory.
---
 pkg_resources/tests/test_pkg_resources.py | 33 ++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/pkg_resources/tests/test_pkg_resources.py b/pkg_resources/tests/test_pkg_resources.py
index 4e2cac94..62a39b8f 100644
--- a/pkg_resources/tests/test_pkg_resources.py
+++ b/pkg_resources/tests/test_pkg_resources.py
@@ -12,6 +12,11 @@ import stat
 import distutils.dist
 import distutils.command.install_egg_info
 
+try:
+    from unittest import mock
+except ImportError:
+    import mock
+
 from pkg_resources.extern.six.moves import map
 from pkg_resources.extern.six import text_type, string_types
 
@@ -138,8 +143,34 @@ class TestResourceManager:
         message = "Unexpected type from get_cache_path: " + type_
         assert isinstance(path, string_types), message
 
+    def test_get_cache_path_race(self, tmpdir):
+        # Patch to os.path.isdir to create a race condition
+        def patched_isdir(dirname, unpatched_isdir=pkg_resources.isdir):
+            patched_isdir.dirnames.append(dirname)
+
+            was_dir = unpatched_isdir(dirname)
+            if not was_dir:
+                os.makedirs(dirname)
+            return was_dir
+
+        patched_isdir.dirnames = []
+
+        # Get a cache path with a "race condition"
+        mgr = pkg_resources.ResourceManager()
+        mgr.set_extraction_path(str(tmpdir))
+
+        archive_name = os.sep.join(('foo', 'bar', 'baz'))
+        with mock.patch.object(pkg_resources, 'isdir', new=patched_isdir):
+            mgr.get_cache_path(archive_name)
+
+        # Because this test relies on the implementation details of this
+        # function, these assertions are a sentinel to ensure that the
+        # test suite will not fail silently if the implementation changes.
+        called_dirnames = patched_isdir.dirnames
+        assert len(called_dirnames) == 2
+        assert called_dirnames[0].split(os.sep)[-2:] == ['foo', 'bar']
+        assert called_dirnames[1].split(os.sep)[-1:] == ['foo']
 
-class TestIndependence:
     """
     Tests to ensure that pkg_resources runs independently from setuptools.
     """
-- 
cgit v1.2.1


From 342443f5034851bbd55823f2c900d7ebabe1b306 Mon Sep 17 00:00:00 2001
From: Paul Ganssle <paul@ganssle.io>
Date: Wed, 11 Jul 2018 10:23:55 -0400
Subject: Fix race condition in _bypass_ensure_directory

This fixes a race condition in _bypass_ensure_directory where
two threads or processes may erroneously fail because they are
both creating the same directory. A more robust implementation
of this may involve exposing the un-wrapped os.makedirs.

Originally reported with proposed patch by @JonKohler in
github PR #1412. This patch came out of discussions on that
thread.
---
 pkg_resources/__init__.py | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/pkg_resources/__init__.py b/pkg_resources/__init__.py
index 67015408..4f42156d 100644
--- a/pkg_resources/__init__.py
+++ b/pkg_resources/__init__.py
@@ -47,6 +47,11 @@ except ImportError:
     # Python 3.2 compatibility
     import imp as _imp
 
+try:
+    FileExistsError
+except NameError:
+    FileExistsError = OSError
+
 from pkg_resources.extern import six
 from pkg_resources.extern.six.moves import urllib, map, filter
 
@@ -3030,7 +3035,10 @@ def _bypass_ensure_directory(path):
     dirname, filename = split(path)
     if dirname and filename and not isdir(dirname):
         _bypass_ensure_directory(dirname)
-        mkdir(dirname, 0o755)
+        try:
+            mkdir(dirname, 0o755)
+        except FileExistsError:
+            pass
 
 
 def split_sections(s):
-- 
cgit v1.2.1


From 67f190adf28d433f0d43ad5014a3fe66f43eb551 Mon Sep 17 00:00:00 2001
From: Jon Kohler <jon@nutanix.com>
Date: Mon, 9 Jul 2018 13:14:33 -0400
Subject: Changelog for github PR #1418

---
 changelog.d/1418.change.rst | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog.d/1418.change.rst

diff --git a/changelog.d/1418.change.rst b/changelog.d/1418.change.rst
new file mode 100644
index 00000000..d7656f57
--- /dev/null
+++ b/changelog.d/1418.change.rst
@@ -0,0 +1 @@
+Solved race in when creating egg cache directories.
-- 
cgit v1.2.1