Update pytest to 3.7.0

[pyup-bot]

This PR updates pytest from 3.6.4 to 3.7.0.

Changelog

3.7.0

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

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

- `2639 <https://github.com/pytest-dev/pytest/issues/2639>`_: ``pytest_namespace`` has been deprecated.

See the documentation for ``pytest_namespace`` hook for suggestions on how to deal
with this in plugins which use this functionality.


- `3661 <https://github.com/pytest-dev/pytest/issues/3661>`_: Calling a fixture function directly, as opposed to request them in a test function, now issues a ``RemovedInPytest4Warning``. It will be changed into an error in pytest ``4.0``.

This is a great source of confusion to new users, which will often call the fixture functions and request them from test functions interchangeably, which breaks the fixture resolution model.



Features
--------

- `2283 <https://github.com/pytest-dev/pytest/issues/2283>`_: New ``package`` fixture scope: fixtures are finalized when the last test of a *package* finishes. This feature is considered **experimental**, so use it sparingly.


- `3576 <https://github.com/pytest-dev/pytest/issues/3576>`_: ``Node.add_marker`` now supports an ``append=True/False`` parameter to determine whether the mark comes last (default) or first.


- `3579 <https://github.com/pytest-dev/pytest/issues/3579>`_: Fixture ``caplog`` now has a ``messages`` property, providing convenient access to the format-interpolated log messages without the extra data provided by the formatter/handler.


- `3610 <https://github.com/pytest-dev/pytest/issues/3610>`_: New ``--trace`` option to enter the debugger at the start of a test.


- `3623 <https://github.com/pytest-dev/pytest/issues/3623>`_: Introduce ``pytester.copy_example`` as helper to do acceptance tests against examples from the project.



Bug Fixes
---------

- `2220 <https://github.com/pytest-dev/pytest/issues/2220>`_: Fix a bug where fixtures overridden by direct parameters (for example parametrization) were being instantiated even if they were not being used by a test.


- `3695 <https://github.com/pytest-dev/pytest/issues/3695>`_: Fix ``ApproxNumpy`` initialisation argument mixup, ``abs`` and ``rel`` tolerances were flipped causing strange comparsion results.
Add tests to check ``abs`` and ``rel`` tolerances for ``np.array`` and test for expecting ``nan`` with ``np.array()``


- `980 <https://github.com/pytest-dev/pytest/issues/980>`_: Fix truncated locals output in verbose mode.



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

- `3295 <https://github.com/pytest-dev/pytest/issues/3295>`_: Correct the usage documentation of ``--last-failed-no-failures`` by adding the missing ``--last-failed`` argument in the presented examples, because they are misleading and lead to think that the missing argument is not needed.



Trivial/Internal Changes
------------------------

- `3519 <https://github.com/pytest-dev/pytest/issues/3519>`_: Now a ``README.md`` file is created in ``.pytest_cache`` to make it clear why the directory exists.

Links

• PyPI: https://pypi.org/project/pytest
• Changelog: https://pyup.io/changelogs/pytest/
• Repo: https://github.com/pytest-dev/pytest/issues
• Homepage: http://pytest.org