Drop support for EOL Python 3.4 (2)

[hugovk]

Continuation of PR #6685.

As suggested in review, that PR was just for removing Python 3.4 from classifiers, CI, its deprecation warnings, and so on.

And here's a new PR for the other 3.4-related removals.

[hugovk]

Please let me know if this needs a news entry or a trivial file/label.

[pradyunsg]

Thanks again for picking this up @hugovk! Trivial sounds good. I've gone ahead and added the equivalent label, so less work for you. :)

[cjerdonek]

I think it might be better to use the PY2 and PY3 constants because cases like these are what they’re for and we use them elsewhere (and it reads more simply, etc).

[xavfernandez]

I agree with @cjerdonek : you should be able to use from pip._vendor.six import PY3 in most of those places :)

[hugovk]

Good idea, updated!

flake8 is failing:

tests/functional/test_install.py:14:1: F401 'pip._vendor.six.PY2' imported but unused
tests/functional/test_install.py:14:1: F401 'pip._vendor.six.PY3' imported but unused

But they're used in decorators like this:

@pytest.mark.skipif("PY2")

How should we fix it?

---

I'd assume Python 2.7 will be dropped before Python 4.0 is released, and these constants removed. On the off-chance it's not(!), remember to review the use of PY3 :)

[pradyunsg]

They're not valid in the decorators.

You'll want leave the pytest decorator as is.

[hugovk]

Thanks, I've reset and re-committed without changing the decorators.

[xavfernandez]

@pradyunsg @pytest.mark.skipif("pip._vendor.six.PY3") seems to work if import pip._vendor.six is imported.

[hugovk]

Should we put a # noqa: F401 on the import to prevent this flake8 warning?

diff --git a/tests/functional/test_install.py b/tests/functional/test_install.py
index e7b6a272..e915892f 100644
--- a/tests/functional/test_install.py
+++ b/tests/functional/test_install.py
@@ -5,6 +5,7 @@ import sys
 import textwrap
 from os.path import curdir, join, pardir

+import pip._vendor.six
 import pytest

 from pip._internal import pep425tags
@@ -528,7 +529,7 @@ def test_editable_install__local_dir_no_setup_py_with_pyproject(
     assert 'A "pyproject.toml" file was found' in msg


-@pytest.mark.skipif("sys.version_info >= (3,)")
+@pytest.mark.skipif("pip._vendor.six.PY3")
 @pytest.mark.xfail
 def test_install_argparse_shadowed(script):
     # When argparse is in the stdlib, we support installing it
@@ -543,7 +544,7 @@ def test_install_argparse_shadowed(script):


 @pytest.mark.network
-@pytest.mark.skipif("sys.version_info < (3,)")
+@pytest.mark.skipif("pip._vendor.six.PY2")
 def test_upgrade_argparse_shadowed(script):
     # If argparse is installed - even if shadowed for imported - we support
     # upgrading it and properly remove the older versions files.

->

$ tox -e lint-py3
...
lint-py3 run-test: commands[0] | flake8
./tests/functional/test_install.py:10:1: F401 'pip._vendor.six' imported but unused

[pradyunsg]

@pytest.mark.skipif("pip._vendor.six.PY3") seems to work if import pip._vendor.six is imported.

IIRC we have other uses of the current style in this PR. Personally, I'm ambivalent so anything works. :)

[chrahunt]

2 small comments, otherwise LGTM.

[pradyunsg]

Looks good to me. I'll merge this eagerly -- if someone spots anything else, let's do it in a follow up PR.

[pradyunsg]

Thanks for all your work on this @hugovk! Thanks for the reviews and inputs @xavfernandez @pfmoore @cjerdonek @chrahunt!

[hugovk]

You're welcome and thanks for the reviews!