43 lines
1.6 KiB
Python
43 lines
1.6 KiB
Python
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"""Import workaround so that Bazel, Py2/Py3, and enum34 package work together.
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This works around a problem due to the combination of Bazel putting
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third party packages before the stdlib in PYTHONPATH. What happens is:
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* The enum34 PyPi package is imported as 'enum'.
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* Bazel puts the path to enum34 before the stdlib, hence 'import enum'
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will prefer to use enum34 from above instead of the stdlib.
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* In Python 3, enum34 is used instead of the stdlib, which breaks
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lots of things. It works fine in Python 2, since there is no enum
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module.
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To work around this, we do 3 things:
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1. Put the enum34 code on PYTHONPATH, but not directly importable as
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'enum'; it is under the (non importable) directory name with the
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PyPi package name and version.
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2. Try to import enum normally, if it works, great. This makes Py3 work
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(as well as Py2 when enum is available as normal).
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3. If the normal enum import failed, then try to find the enum34
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entry on sys.path, and append the missing directory name.
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Once it is successfully imported, expose the module directly. This
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prevents importing the module twice under different names. e.g.,
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the following is true:
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from absl._enum_module import enum as absl_enum
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import enum as normal_enum
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assert absl_enum is normal_enum
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"""
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# pylint: disable=unused-import
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import sys
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import six
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try:
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import enum
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except ImportError:
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if six.PY3:
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# While not all Py3's have enum, only the ones we support do.
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raise
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for i, path in enumerate(sys.path):
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if '/enum34_archive' in path:
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sys.path[i] = path + '/enum34-1.1.6'
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import enum
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