Update pip to 20.2.3

[pyup-bot]

This PR updates pip from 19.1.1 to 20.2.3.

Changelog

20.2.3

===================

Deprecations and Removals
-------------------------

- Deprecate support for Python 3.5 (`8181 <https://github.com/pypa/pip/issues/8181>`_)

Features
--------

- Make the ``setup.py install`` deprecation warning less noisy. We warn only
when ``setup.py install`` succeeded and ``setup.py bdist_wheel`` failed, as
situations where both fails are most probably irrelevant to this deprecation. (`8752 <https://github.com/pypa/pip/issues/8752>`_)

20.2.2

===================

Bug Fixes
---------

- Only attempt to use the keyring once and if it fails, don't try again.
This prevents spamming users with several keyring unlock prompts when they
cannot unlock or don't want to do so. (`8090 <https://github.com/pypa/pip/issues/8090>`_)
- Fix regression that distributions in system site-packages are not correctly
found when a virtual environment is configured with ``system-site-packages``
on. (`8695 <https://github.com/pypa/pip/issues/8695>`_)
- Disable caching for range requests, which causes corrupted wheels
when pip tries to obtain metadata using the feature ``fast-deps``. (`8701 <https://github.com/pypa/pip/issues/8701>`_, `8716 <https://github.com/pypa/pip/issues/8716>`_)
- Always use UTF-8 to read ``pyvenv.cfg`` to match the built-in ``venv``. (`8717 <https://github.com/pypa/pip/issues/8717>`_)
- 2020 Resolver: Correctly handle marker evaluation in constraints and exclude
them if their markers do not match the current environment. (`8724 <https://github.com/pypa/pip/issues/8724>`_)

20.2.1

===================

Features
--------

- Ignore require-virtualenv in ``pip list`` (`8603 <https://github.com/pypa/pip/issues/8603>`_)

Bug Fixes
---------

- Correctly find already-installed distributions with dot (``.``) in the name
and uninstall them when needed. (`8645 <https://github.com/pypa/pip/issues/8645>`_)
- Trace a better error message on installation failure due to invalid ``.data``
files in wheels. (`8654 <https://github.com/pypa/pip/issues/8654>`_)
- Fix SVN version detection for alternative SVN distributions. (`8665 <https://github.com/pypa/pip/issues/8665>`_)
- New resolver: Correctly include the base package when specified with extras
in ``--no-deps`` mode. (`8677 <https://github.com/pypa/pip/issues/8677>`_)
- Use UTF-8 to handle ZIP archive entries on Python 2 according to PEP 427, so
non-ASCII paths can be resolved as expected. (`8684 <https://github.com/pypa/pip/issues/8684>`_)

Improved Documentation
----------------------

- Add details on old resolver deprecation and removal to migration documentation. (`8371 <https://github.com/pypa/pip/issues/8371>`_)
- Fix feature flag name in docs. (`8660 <https://github.com/pypa/pip/issues/8660>`_)

20.2

=================

Deprecations and Removals
-------------------------

- Deprecate setup.py-based builds that do not generate an ``.egg-info`` directory. (`6998 <https://github.com/pypa/pip/issues/6998>`_, `8617 <https://github.com/pypa/pip/issues/8617>`_)
- Disallow passing install-location-related arguments in ``--install-options``. (`7309 <https://github.com/pypa/pip/issues/7309>`_)
- Add deprecation warning for invalid requirements format "base>=1.0[extra]" (`8288 <https://github.com/pypa/pip/issues/8288>`_)
- Deprecate legacy setup.py install when building a wheel failed for source
distributions without pyproject.toml (`8368 <https://github.com/pypa/pip/issues/8368>`_)
- Deprecate -b/--build/--build-dir/--build-directory. Its current behaviour is confusing
and breaks in case different versions of the same distribution need to be built during
the resolution process. Using the TMPDIR/TEMP/TMP environment variable, possibly
combined with --no-clean covers known use cases. (`8372 <https://github.com/pypa/pip/issues/8372>`_)
- Remove undocumented and deprecated option ``--always-unzip`` (`8408 <https://github.com/pypa/pip/issues/8408>`_)

Features
--------

- Log debugging information about pip, in ``pip install --verbose``. (`3166 <https://github.com/pypa/pip/issues/3166>`_)
- Refine error messages to avoid showing Python tracebacks when an HTTP error occurs. (`5380 <https://github.com/pypa/pip/issues/5380>`_)
- Install wheel files directly instead of extracting them to a temp directory. (`6030 <https://github.com/pypa/pip/issues/6030>`_)
- Add a beta version of pip's next-generation dependency resolver.

Move pip's new resolver into beta, remove the
``--unstable-feature=resolver`` flag, and enable the
``--use-feature=2020-resolver`` flag. The new resolver is
significantly stricter and more consistent when it receives
incompatible instructions, and reduces support for certain kinds of
:ref:`Constraints Files`, so some workarounds and workflows may
break. More details about how to test and migrate, and how to report
issues, at :ref:`Resolver changes 2020` . Maintainers are preparing to

20.2b1

===================

Bug Fixes
---------

- Correctly treat wheels containing non-ASCII file contents so they can be
installed on Windows. (`5712 <https://github.com/pypa/pip/issues/5712>`_)
- Prompt the user for password if the keyring backend doesn't return one (`7998 <https://github.com/pypa/pip/issues/7998>`_)

Improved Documentation
----------------------

- Add GitHub issue template for reporting when the dependency resolver fails (`8207 <https://github.com/pypa/pip/issues/8207>`_)

20.1.1

===================

Deprecations and Removals
-------------------------

- Revert building of local directories in place, restoring the pre-20.1
behaviour of copying to a temporary directory. (`7555 <https://github.com/pypa/pip/issues/7555>`_)
- Drop parallelization from ``pip list --outdated``. (`8167 <https://github.com/pypa/pip/issues/8167>`_)

Bug Fixes
---------

- Fix metadata permission issues when umask has the executable bit set. (`8164 <https://github.com/pypa/pip/issues/8164>`_)
- Avoid unnecessary message about the wheel package not being installed
when a wheel would not have been built. Additionally, clarify the message. (`8178 <https://github.com/pypa/pip/issues/8178>`_)

20.1

=================

Process
-------

- Document that pip 21.0 will drop support for Python 2.7.

Features
--------

- Add ``pip cache dir`` to show the cache directory. (`7350 <https://github.com/pypa/pip/issues/7350>`_)

Bug Fixes
---------

- Abort pip cache commands early when cache is disabled. (`8124 <https://github.com/pypa/pip/issues/8124>`_)
- Correctly set permissions on metadata files during wheel installation,
to permit non-privileged users to read from system site-packages. (`8139 <https://github.com/pypa/pip/issues/8139>`_)

20.1b1

===================

Deprecations and Removals
-------------------------

- Remove emails from AUTHORS.txt to prevent usage for spamming, and only populate names in AUTHORS.txt at time of release (`5979 <https://github.com/pypa/pip/issues/5979>`_)
- Remove deprecated ``--skip-requirements-regex`` option. (`7297 <https://github.com/pypa/pip/issues/7297>`_)
- Building of local directories is now done in place, instead of a temporary
location containing a copy of the directory tree. (`7555 <https://github.com/pypa/pip/issues/7555>`_)
- Remove unused ``tests/scripts/test_all_pip.py`` test script and the ``tests/scripts`` folder. (`7680 <https://github.com/pypa/pip/issues/7680>`_)

Features
--------

- pip now implements PEP 610, so ``pip freeze`` has better fidelity
in presence of distributions installed from Direct URL requirements. (`609 <https://github.com/pypa/pip/issues/609>`_)
- Add ``pip cache`` command for inspecting/managing pip's wheel cache. (`6391 <https://github.com/pypa/pip/issues/6391>`_)
- Raise error if ``--user`` and ``--target`` are used together in ``pip install`` (`7249 <https://github.com/pypa/pip/issues/7249>`_)
- Significantly improve performance when ``--find-links`` points to a very large HTML page. (`7729 <https://github.com/pypa/pip/issues/7729>`_)
- Indicate when wheel building is skipped, due to lack of the ``wheel`` package. (`7768 <https://github.com/pypa/pip/issues/7768>`_)
- Change default behaviour to always cache responses from trusted-host source. (`7847 <https://github.com/pypa/pip/issues/7847>`_)
- An alpha version of a new resolver is available via ``--unstable-feature=resolver``. (`988 <https://github.com/pypa/pip/issues/988>`_)

Bug Fixes
---------

- Correctly freeze a VCS editable package when it is nested inside another VCS repository. (`3988 <https://github.com/pypa/pip/issues/3988>`_)
- Correctly handle ``%2F`` in URL parameters to avoid accidentally unescape them
into ``/``. (`6446 <https://github.com/pypa/pip/issues/6446>`_)
- Reject VCS URLs with an empty revision. (`7402 <https://github.com/pypa/pip/issues/7402>`_)
- Warn when an invalid URL is passed with ``--index-url`` (`7430 <https://github.com/pypa/pip/issues/7430>`_)
- Use better mechanism for handling temporary files, when recording metadata
about installed files (RECORD) and the installer (INSTALLER). (`7699 <https://github.com/pypa/pip/issues/7699>`_)
- Correctly detect global site-packages availability of virtual environments
created by PyPA’s virtualenv>=20.0. (`7718 <https://github.com/pypa/pip/issues/7718>`_)
- Remove current directory from ``sys.path`` when invoked as ``python -m pip <command>`` (`7731 <https://github.com/pypa/pip/issues/7731>`_)
- Stop failing uninstallation, when trying to remove non-existent files. (`7856 <https://github.com/pypa/pip/issues/7856>`_)
- Prevent an infinite recursion with ``pip wheel`` when ``$TMPDIR`` is within the source directory. (`7872 <https://github.com/pypa/pip/issues/7872>`_)
- Significantly speedup ``pip list --outdated`` by parallelizing index interaction. (`7962 <https://github.com/pypa/pip/issues/7962>`_)
- Improve Windows compatibility when detecting writability in folder. (`8013 <https://github.com/pypa/pip/issues/8013>`_)

Vendored Libraries
------------------

- Update semi-supported debundling script to reflect that appdirs is vendored.
- Add ResolveLib as a vendored dependency.
- Upgrade certifi to 2020.04.05.1
- Upgrade contextlib2 to 0.6.0.post1
- Upgrade distro to 1.5.0.
- Upgrade idna to 2.9.
- Upgrade msgpack to 1.0.0.
- Upgrade packaging to 20.3.
- Upgrade pep517 to 0.8.2.
- Upgrade pyparsing to 2.4.7.
- Remove pytoml as a vendored dependency.
- Upgrade requests to 2.23.0.
- Add toml as a vendored dependency.
- Upgrade urllib3 to 1.25.8.

Improved Documentation
----------------------

- Emphasize that VCS URLs using git, git+git and git+http are insecure due to
lack of authentication and encryption (`1983 <https://github.com/pypa/pip/issues/1983>`_)
- Clarify the usage of --no-binary command. (`3191 <https://github.com/pypa/pip/issues/3191>`_)
- Clarify the usage of freeze command in the example of Using pip in your program (`7008 <https://github.com/pypa/pip/issues/7008>`_)
- Add a "Copyright" page. (`7767 <https://github.com/pypa/pip/issues/7767>`_)
- Added example of defining multiple values for options which support them (`7803 <https://github.com/pypa/pip/issues/7803>`_)

20.0.2

===================

Bug Fixes
---------

- Fix a regression in generation of compatibility tags. (`7626 <https://github.com/pypa/pip/issues/7626>`_)

Vendored Libraries
------------------

- Upgrade packaging to 20.1

20.0.1

===================

Bug Fixes
---------

- Rename an internal module, to avoid ImportErrors due to improper uninstallation. (`7621 <https://github.com/pypa/pip/issues/7621>`_)

20.0

=================

Process
-------

- Switch to a dedicated CLI tool for vendoring dependencies.

Deprecations and Removals
-------------------------

- Remove wheel tag calculation from pip and use ``packaging.tags``. This
should provide more tags ordered better than in prior releases. (`6908 <https://github.com/pypa/pip/issues/6908>`_)
- Deprecate setup.py-based builds that do not generate an ``.egg-info`` directory. (`6998 <https://github.com/pypa/pip/issues/6998>`_)
- The pip>=20 wheel cache is not retro-compatible with previous versions. Until
pip 21.0, pip will continue to take advantage of existing legacy cache
entries. (`7296 <https://github.com/pypa/pip/issues/7296>`_)
- Deprecate undocumented ``--skip-requirements-regex`` option. (`7297 <https://github.com/pypa/pip/issues/7297>`_)
- Deprecate passing install-location-related options via ``--install-option``. (`7309 <https://github.com/pypa/pip/issues/7309>`_)
- Use literal "abi3" for wheel tag on CPython 3.x, to align with PEP 384
which only defines it for this platform. (`7327 <https://github.com/pypa/pip/issues/7327>`_)
- Remove interpreter-specific major version tag e.g. ``cp3-none-any``
from consideration. This behavior was not documented strictly, and this
tag in particular is `not useful <https://snarky.ca/the-challenges-in-designing-a-library-for-pep-425/>`_.
Anyone with a use case can create an issue with pypa/packaging. (`7355 <https://github.com/pypa/pip/issues/7355>`_)
- Wheel processing no longer permits wheels containing more than one top-level
.dist-info directory. (`7487 <https://github.com/pypa/pip/issues/7487>`_)
- Support for the ``git+git`` form of VCS requirement is being deprecated and
will be removed in pip 21.0. Switch to ``git+https://`` or
``git+ssh://``. ``git+git://`` also works but its use is discouraged as it is
insecure. (`7543 <https://github.com/pypa/pip/issues/7543>`_)

Features
--------

- Default to doing a user install (as if ``--user`` was passed) when the main
site-packages directory is not writeable and user site-packages are enabled. (`1668 <https://github.com/pypa/pip/issues/1668>`_)
- Warn if a path in PATH starts with tilde during ``pip install``. (`6414 <https://github.com/pypa/pip/issues/6414>`_)
- Cache wheels built from Git requirements that are considered immutable,
because they point to a commit hash. (`6640 <https://github.com/pypa/pip/issues/6640>`_)
- Add option ``--no-python-version-warning`` to silence warnings
related to deprecation of Python versions. (`6673 <https://github.com/pypa/pip/issues/6673>`_)
- Cache wheels that ``pip wheel`` built locally, matching what
``pip install`` does. This particularly helps performance in workflows where
``pip wheel`` is used for `building before installing
<https://pip.pypa.io/en/stable/user_guide/installing-from-local-packages>`_.
Users desiring the original behavior can use ``pip wheel --no-cache-dir``. (`6852 <https://github.com/pypa/pip/issues/6852>`_)
- Display CA information in ``pip debug``. (`7146 <https://github.com/pypa/pip/issues/7146>`_)
- Show only the filename (instead of full URL), when downloading from PyPI. (`7225 <https://github.com/pypa/pip/issues/7225>`_)
- Suggest a more robust command to upgrade pip itself to avoid confusion when the
current pip command is not available as ``pip``. (`7376 <https://github.com/pypa/pip/issues/7376>`_)
- Define all old pip console script entrypoints to prevent import issues in
stale wrapper scripts. (`7498 <https://github.com/pypa/pip/issues/7498>`_)
- The build step of ``pip wheel`` now builds all wheels to a cache first,
then copies them to the wheel directory all at once.
Before, it built them to a temporary directory and moved
them to the wheel directory one by one. (`7517 <https://github.com/pypa/pip/issues/7517>`_)
- Expand ``~`` prefix to user directory in path options, configs, and
environment variables. Values that may be either URL or path are not
currently supported, to avoid ambiguity:

* ``--find-links``
* ``--constraint``, ``-c``
* ``--requirement``, ``-r``
* ``--editable``, ``-e`` (`980 <https://github.com/pypa/pip/issues/980>`_)

Bug Fixes
---------

- Correctly handle system site-packages, in virtual environments created with venv (PEP 405). (`5702 <https://github.com/pypa/pip/issues/5702>`_, `7155 <https://github.com/pypa/pip/issues/7155>`_)
- Fix case sensitive comparison of pip freeze when used with -r option. (`5716 <https://github.com/pypa/pip/issues/5716>`_)
- Enforce PEP 508 requirement format in ``pyproject.toml``
``build-system.requires``. (`6410 <https://github.com/pypa/pip/issues/6410>`_)
- Make ``ensure_dir()`` also ignore ``ENOTEMPTY`` as seen on Windows. (`6426 <https://github.com/pypa/pip/issues/6426>`_)
- Fix building packages which specify ``backend-path`` in pyproject.toml. (`6599 <https://github.com/pypa/pip/issues/6599>`_)
- Do not attempt to run ``setup.py clean`` after a ``pep517`` build error,
since a ``setup.py`` may not exist in that case. (`6642 <https://github.com/pypa/pip/issues/6642>`_)
- Fix passwords being visible in the index-url in
"Downloading <url>" message. (`6783 <https://github.com/pypa/pip/issues/6783>`_)
- Change method from shutil.remove to shutil.rmtree in noxfile.py. (`7191 <https://github.com/pypa/pip/issues/7191>`_)
- Skip running tests which require subversion, when svn isn't installed (`7193 <https://github.com/pypa/pip/issues/7193>`_)
- Fix not sending client certificates when using ``--trusted-host``. (`7207 <https://github.com/pypa/pip/issues/7207>`_)
- Make sure ``pip wheel`` never outputs pure python wheels with a
python implementation tag. Better fix/workaround for
`3025 <https://github.com/pypa/pip/issues/3025>`_ by
using a per-implementation wheel cache instead of caching pure python
wheels with an implementation tag in their name. (`7296 <https://github.com/pypa/pip/issues/7296>`_)
- Include ``subdirectory`` URL fragments in cache keys. (`7333 <https://github.com/pypa/pip/issues/7333>`_)
- Fix typo in warning message when any of ``--build-option``, ``--global-option``
and ``--install-option`` is used in requirements.txt (`7340 <https://github.com/pypa/pip/issues/7340>`_)
- Fix the logging of cached HTTP response shown as downloading. (`7393 <https://github.com/pypa/pip/issues/7393>`_)
- Effectively disable the wheel cache when it is not writable, as is the
case with the http cache. (`7488 <https://github.com/pypa/pip/issues/7488>`_)
- Correctly handle relative cache directory provided via --cache-dir. (`7541 <https://github.com/pypa/pip/issues/7541>`_)

Vendored Libraries
------------------

- Upgrade CacheControl to 0.12.5
- Upgrade certifi to 2019.9.11
- Upgrade colorama to 0.4.1
- Upgrade distlib to 0.2.9.post0
- Upgrade ipaddress to 1.0.22
- Update packaging to 20.0.
- Upgrade pkg_resources (via setuptools) to 44.0.0
- Upgrade pyparsing to 2.4.2
- Upgrade six to 1.12.0
- Upgrade urllib3 to 1.25.6

Improved Documentation
----------------------

- Document that "coding: utf-8" is supported in requirements.txt (`7182 <https://github.com/pypa/pip/issues/7182>`_)
- Explain how to get pip's source code in `Getting Started <https://pip.pypa.io/en/stable/development/getting-started/>`_ (`7197 <https://github.com/pypa/pip/issues/7197>`_)
- Describe how basic authentication credentials in URLs work. (`7201 <https://github.com/pypa/pip/issues/7201>`_)
- Add more clear installation instructions (`7222 <https://github.com/pypa/pip/issues/7222>`_)
- Fix documentation links for index options (`7347 <https://github.com/pypa/pip/issues/7347>`_)
- Better document the requirements file format (`7385 <https://github.com/pypa/pip/issues/7385>`_)

19.3.1

===================

Features
--------

- Document Python 3.8 support. (`7219 <https://github.com/pypa/pip/issues/7219>`_)

Bug Fixes
---------

- Fix bug that prevented installation of PEP 517 packages without ``setup.py``. (`6606 <https://github.com/pypa/pip/issues/6606>`_)

19.3

=================

Deprecations and Removals
-------------------------

- Remove undocumented support for un-prefixed URL requirements pointing
to SVN repositories. Users relying on this can get the original behavior
by prefixing their URL with ``svn+`` (which is backwards-compatible). (`7037 <https://github.com/pypa/pip/issues/7037>`_)
- Remove the deprecated ``--venv`` option from ``pip config``. (`7163 <https://github.com/pypa/pip/issues/7163>`_)

Features
--------

- Print a better error message when ``--no-binary`` or ``--only-binary`` is given
an argument starting with ``-``. (`3191 <https://github.com/pypa/pip/issues/3191>`_)
- Make ``pip show`` warn about packages not found. (`6858 <https://github.com/pypa/pip/issues/6858>`_)
- Support including a port number in ``--trusted-host`` for both HTTP and HTTPS. (`6886 <https://github.com/pypa/pip/issues/6886>`_)
- Redact single-part login credentials from URLs in log messages. (`6891 <https://github.com/pypa/pip/issues/6891>`_)
- Implement manylinux2014 platform tag support.  manylinux2014 is the successor
to manylinux2010.  It allows carefully compiled binary wheels to be installed
on compatible Linux platforms.  The manylinux2014 platform tag definition can
be found in `PEP599 <https://www.python.org/dev/peps/pep-0599/>`_. (`7102 <https://github.com/pypa/pip/issues/7102>`_)

Bug Fixes
---------

- Abort installation if any archive contains a file which would be placed
outside the extraction location. (`3907 <https://github.com/pypa/pip/issues/3907>`_)
- pip's CLI completion code no longer prints a Traceback if it is interrupted. (`3942 <https://github.com/pypa/pip/issues/3942>`_)
- Correct inconsistency related to the ``hg+file`` scheme. (`4358 <https://github.com/pypa/pip/issues/4358>`_)
- Fix ``rmtree_errorhandler`` to skip non-existing directories. (`4910 <https://github.com/pypa/pip/issues/4910>`_)
- Ignore errors copying socket files for local source installs (in Python 3). (`5306 <https://github.com/pypa/pip/issues/5306>`_)
- Fix requirement line parser to correctly handle PEP 440 requirements with a URL
pointing to an archive file. (`6202 <https://github.com/pypa/pip/issues/6202>`_)
- The ``pip-wheel-metadata`` directory does not need to persist between invocations of pip, use a temporary directory instead of the current ``setup.py`` directory. (`6213 <https://github.com/pypa/pip/issues/6213>`_)
- Fix ``--trusted-host`` processing under HTTPS to trust any port number used
with the host. (`6705 <https://github.com/pypa/pip/issues/6705>`_)
- Switch to new ``distlib`` wheel script template. This should be functionally
equivalent for end users. (`6763 <https://github.com/pypa/pip/issues/6763>`_)
- Skip copying .tox and .nox directories to temporary build directories (`6770 <https://github.com/pypa/pip/issues/6770>`_)
- Fix handling of tokens (single part credentials) in URLs. (`6795 <https://github.com/pypa/pip/issues/6795>`_)
- Fix a regression that caused ``~`` expansion not to occur in ``--find-links``
paths. (`6804 <https://github.com/pypa/pip/issues/6804>`_)
- Fix bypassed pip upgrade warning on Windows. (`6841 <https://github.com/pypa/pip/issues/6841>`_)
- Fix 'm' flag erroneously being appended to ABI tag in Python 3.8 on platforms that do not provide SOABI (`6885 <https://github.com/pypa/pip/issues/6885>`_)
- Hide security-sensitive strings like passwords in log messages related to
version control system (aka VCS) command invocations. (`6890 <https://github.com/pypa/pip/issues/6890>`_)
- Correctly uninstall symlinks that were installed in a virtualenv,
by tools such as ``flit install --symlink``. (`6892 <https://github.com/pypa/pip/issues/6892>`_)
- Don't fail installation using pip.exe on Windows when pip wouldn't be upgraded. (`6924 <https://github.com/pypa/pip/issues/6924>`_)
- Use canonical distribution names when computing ``Required-By`` in ``pip show``. (`6947 <https://github.com/pypa/pip/issues/6947>`_)
- Don't use hardlinks for locking selfcheck state file. (`6954 <https://github.com/pypa/pip/issues/6954>`_)
- Ignore "require_virtualenv" in ``pip config`` (`6991 <https://github.com/pypa/pip/issues/6991>`_)
- Fix ``pip freeze`` not showing correct entry for mercurial packages that use subdirectories. (`7071 <https://github.com/pypa/pip/issues/7071>`_)
- Fix a crash when ``sys.stdin`` is set to ``None``, such as on AWS Lambda. (`7118 <https://github.com/pypa/pip/issues/7118>`_, `7119 <https://github.com/pypa/pip/issues/7119>`_)

Vendored Libraries
------------------

- Upgrade certifi to 2019.9.11
- Add contextlib2 0.6.0 as a vendored dependency.
- Remove Lockfile as a vendored dependency.
- Upgrade msgpack to 0.6.2
- Upgrade packaging to 19.2
- Upgrade pep517 to 0.7.0
- Upgrade pyparsing to 2.4.2
- Upgrade pytoml to 0.1.21
- Upgrade setuptools to 41.4.0
- Upgrade urllib3 to 1.25.6

Improved Documentation
----------------------

- Document caveats for UNC paths in uninstall and add .pth unit tests. (`6516 <https://github.com/pypa/pip/issues/6516>`_)
- Add architectural overview documentation. (`6637 <https://github.com/pypa/pip/issues/6637>`_)
- Document that ``--ignore-installed`` is dangerous. (`6794 <https://github.com/pypa/pip/issues/6794>`_)

19.2.3

===================

Bug Fixes
---------

- Fix 'm' flag erroneously being appended to ABI tag in Python 3.8 on platforms that do not provide SOABI (`6885 <https://github.com/pypa/pip/issues/6885>`_)

19.2.2

===================

Bug Fixes
---------

- Fix handling of tokens (single part credentials) in URLs. (`6795 <https://github.com/pypa/pip/issues/6795>`_)
- Fix a regression that caused ``~`` expansion not to occur in ``--find-links``
paths. (`6804 <https://github.com/pypa/pip/issues/6804>`_)

19.2.1

===================

Bug Fixes
---------

- Fix a ``NoneType`` ``AttributeError`` when evaluating hashes and no hashes
are provided. (`6772 <https://github.com/pypa/pip/issues/6772>`_)

19.2

=================

Deprecations and Removals
-------------------------

- Drop support for EOL Python 3.4. (`6685 <https://github.com/pypa/pip/issues/6685>`_)
- Improve deprecation messages to include the version in which the functionality will be removed. (`6549 <https://github.com/pypa/pip/issues/6549>`_)

Features
--------

- Credentials will now be loaded using `keyring` when installed. (`5948 <https://github.com/pypa/pip/issues/5948>`_)
- Fully support using ``--trusted-host`` inside requirements files. (`3799 <https://github.com/pypa/pip/issues/3799>`_)
- Update timestamps in pip's ``--log`` file to include milliseconds. (`6587 <https://github.com/pypa/pip/issues/6587>`_)
- Respect whether a file has been marked as "yanked" from a simple repository
(see `PEP 592 <https://www.python.org/dev/peps/pep-0592/>`__ for details). (`6633 <https://github.com/pypa/pip/issues/6633>`_)
- When choosing candidates to install, prefer candidates with a hash matching
one of the user-provided hashes. (`5874 <https://github.com/pypa/pip/issues/5874>`_)
- Improve the error message when ``METADATA`` or ``PKG-INFO`` is None when
accessing metadata. (`5082 <https://github.com/pypa/pip/issues/5082>`_)
- Add a new command ``pip debug`` that can display e.g. the list of compatible
tags for the current Python. (`6638 <https://github.com/pypa/pip/issues/6638>`_)
- Display hint on installing with --pre when search results include pre-release versions. (`5169 <https://github.com/pypa/pip/issues/5169>`_)
- Report to Warehouse that pip is running under CI if the ``PIP_IS_CI`` environment variable is set. (`5499 <https://github.com/pypa/pip/issues/5499>`_)
- Allow ``--python-version`` to be passed as a dotted version string (e.g.
``3.7`` or ``3.7.3``). (`6585 <https://github.com/pypa/pip/issues/6585>`_)
- Log the final filename and SHA256 of a ``.whl`` file when done building a
wheel. (`5908 <https://github.com/pypa/pip/issues/5908>`_)
- Include the wheel's tags in the log message explanation when a candidate
wheel link is found incompatible. (`6121 <https://github.com/pypa/pip/issues/6121>`_)
- Add a ``--path`` argument to ``pip freeze`` to support ``--target``
installations. (`6404 <https://github.com/pypa/pip/issues/6404>`_)
- Add a ``--path`` argument to ``pip list`` to support ``--target``
installations. (`6551 <https://github.com/pypa/pip/issues/6551>`_)

Bug Fixes
---------

- Set ``sys.argv[0]`` to the underlying ``setup.py`` when invoking ``setup.py``
via the setuptools shim so setuptools doesn't think the path is ``-c``. (`1890 <https://github.com/pypa/pip/issues/1890>`_)
- Update ``pip download`` to respect the given ``--python-version`` when checking
``"Requires-Python"``. (`5369 <https://github.com/pypa/pip/issues/5369>`_)
- Respect ``--global-option`` and ``--install-option`` when installing from
a version control url (e.g. ``git``). (`5518 <https://github.com/pypa/pip/issues/5518>`_)
- Make the "ascii" progress bar really be "ascii" and not Unicode. (`5671 <https://github.com/pypa/pip/issues/5671>`_)
- Fail elegantly when trying to set an incorrectly formatted key in config. (`5963 <https://github.com/pypa/pip/issues/5963>`_)
- Prevent DistutilsOptionError when prefix is indicated in the global environment and `--target` is used. (`6008 <https://github.com/pypa/pip/issues/6008>`_)
- Fix ``pip install`` to respect ``--ignore-requires-python`` when evaluating
links. (`6371 <https://github.com/pypa/pip/issues/6371>`_)
- Fix a debug log message when freezing an editable, non-version controlled
requirement. (`6383 <https://github.com/pypa/pip/issues/6383>`_)
- Extend to Subversion 1.8+ the behavior of calling Subversion in
interactive mode when pip is run interactively. (`6386 <https://github.com/pypa/pip/issues/6386>`_)
- Prevent ``pip install <url>`` from permitting directory traversal if e.g.
a malicious server sends a ``Content-Disposition`` header with a filename
containing ``../`` or ``..\\``. (`6413 <https://github.com/pypa/pip/issues/6413>`_)
- Hide passwords in output when using ``--find-links``. (`6489 <https://github.com/pypa/pip/issues/6489>`_)
- Include more details in the log message if ``pip freeze`` can't generate a
requirement string for a particular distribution. (`6513 <https://github.com/pypa/pip/issues/6513>`_)
- Add the line number and file location to the error message when reading an
invalid requirements file in certain situations. (`6527 <https://github.com/pypa/pip/issues/6527>`_)
- Prefer ``os.confstr`` to ``ctypes`` when extracting glibc version info. (`6543 <https://github.com/pypa/pip/issues/6543>`_, `6675 <https://github.com/pypa/pip/issues/6675>`_)
- Improve error message printed when an invalid editable requirement is provided. (`6648 <https://github.com/pypa/pip/issues/6648>`_)
- Improve error message formatting when a command errors out in a subprocess. (`6651 <https://github.com/pypa/pip/issues/6651>`_)

Vendored Libraries
------------------

- Upgrade certifi to 2019.6.16
- Upgrade distlib to 0.2.9.post0
- Upgrade msgpack to 0.6.1
- Upgrade requests to 2.22.0
- Upgrade urllib3 to 1.25.3
- Patch vendored html5lib, to prefer using `collections.abc` where possible.

Improved Documentation
----------------------

- Document how Python 2.7 support will be maintained. (`6726 <https://github.com/pypa/pip/issues/6726>`_)
- Upgrade Sphinx version used to build documentation. (`6471 <https://github.com/pypa/pip/issues/6471>`_)
- Fix generation of subcommand manpages. (`6724 <https://github.com/pypa/pip/issues/6724>`_)
- Mention that pip can install from git refs. (`6512 <https://github.com/pypa/pip/issues/6512>`_)
- Replace a failing example of pip installs with extras with a working one. (`4733 <https://github.com/pypa/pip/issues/4733>`_)

Links

• PyPI: https://pypi.org/project/pip
• Changelog: https://pyup.io/changelogs/pip/
• Homepage: https://pip.pypa.io/

[pyup-bot]

Closing this in favor of #195