Fallback from pip._vendor imports to environment wide imports

pip_accel/req.py

@@ -1,7 +1,7 @@
 # Accelerator for pip, the Python package manager.
 #
 # Author: Peter Odding <[email protected]>
-# Last Change: November 7, 2015
+# Last Change: January 17, 2016
 # URL: https://github.com/paylogic/pip-accel
 
 """
@@ -38,10 +38,17 @@
 
 # External dependencies.
 from cached_property import cached_property
-from pip._vendor.distlib.util import ARCHIVE_EXTENSIONS
-from pip._vendor.pkg_resources import find_distributions
 from pip.req import InstallRequirement
 
+# The following package(s) are usually bundled with pip but may be unbundled
+# by redistributors and pip-accel should handle this gracefully.
+try:
+ from pip._vendor.distlib.util import ARCHIVE_EXTENSIONS
+ from pip._vendor.pkg_resources import find_distributions
+except ImportError:
+ from distlib.util import ARCHIVE_EXTENSIONS
+ from pkg_resources import find_distributions
+
 
 class Requirement(object):
 

pip_accel/utils.py

@@ -1,7 +1,7 @@
 # Utility functions for the pip accelerator.
 #
 # Author: Peter Odding <[email protected]>
-# Last Change: January 10, 2016
+# Last Change: January 17, 2016
 # URL: https://github.com/paylogic/pip-accel
 
 """
@@ -26,12 +26,13 @@
 # External dependencies.
 from humanfriendly import parse_path
 from pip.commands.uninstall import UninstallCommand
-from pip._vendor.pkg_resources import (
- DistributionNotFound,
- WorkingSet,
- get_distribution,
- parse_requirements,
-)
+
+# The following package(s) are usually bundled with pip but may be unbundled
+# by redistributors and pip-accel should handle this gracefully.
+try:
+ from pip._vendor.pkg_resources import DistributionNotFound, WorkingSet, get_distribution, parse_requirements
+except ImportError:
+ from pkg_resources import DistributionNotFound, WorkingSet, get_distribution, parse_requirements
 
 # Initialize a logger for this module.
 logger = logging.getLogger(__name__)