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Virtualenv fixture for py.test

Project description

Create a Python virtual environment in your test that cleans up on teardown. The fixture has utility methods to install packages and list what’s installed.


Install using your favourite package installer:

pip install pytest-virtualenv
# or
easy_install pytest-virtualenv

Enable the fixture explicitly in your tests or (not required when using setuptools entry points):

pytest_plugins = ['pytest_virtualenv']


This fixture is configured using the following evironment variables

Setting Description Default
VIRTUALENV_FIXTURE_EXECUTABLE Which virtualenv executable will be used to create new venvs virtualenv

Fixture Attributes

Here’s a noddy test case to demonstrate the basic fixture attributes. For more information on see

def test_virtualenv(virtualenv):
    # the 'virtualenv' attribute is a `` object for the root of the virtualenv
    dirnames = virtualenv.virtualenv.dirs()
    assert {'bin', 'include', 'lib'}.intersection(set(dirnames))

    # the 'python' attribute is a `` object for the python executable
    assert virtualenv.python.endswith('/bin/python')

Installing Packages

You can install packages by name and query what’s installed.

def test_installing(virtualenv):
    virtualenv.install_package('coverage', installer='pip')

    # installed_packages() will return a list of `PackageEntry` objects.
    assert 'coverage' in [ for i in virtualenv.installed_packages()]

Developing Source Checkouts

Any packages set up in the test runner’s python environment (ie, the same runtime that py.test is installed in) as source checkouts using python develop will be detected as such and can be installed by name using install_package. By default they are installed into the virtualenv using python develop, there is an option to build and install an egg as well:

def test_installing_source(virtualenv):
    # Install a source checkout of my_package as an egg file
    virtualenv.install_package('my_package',  build_egg=True)

Running Commands

The test fixture has a run method which allows you to run commands with the correct paths set up as if you had activated the virtualenv first.

def test_run(virtualenv):
    python_exe_path  = virtualenv.python
    runtime_exe ="python -c 'import sys; print sys.executable'", capture=True)
    assert runtime_exe == python_exe_path

Running Commands With Coverage

The test fixture has a run_with_coverage method which is like run but runs the command under coverage inside the virtualenv. This is useful for capturing test coverage on tools that are being tested outside the normal test runner environment.

def test_coverage(virtualenv):
    # You will have to install coverage first
    virtualenv.run_with_coverage(["my_entry_point", "--arg1", "--arg2"])


1.3.0 (2017-11-17)

  • Fixed workspace deletion when teardown is None
  • Fixed squash of root logger in pytest-listener
  • Added S3 Minio fixture (many thanks to Gavin Bisesi)
  • Added Postgres fixture (many thanks to Gavin Bisesi)
  • Use requests for server fixtures http gets as it handles redirects and proxies properly

1.2.12 (2017-8-1)

  • Fixed regression on cacheing ephemeral hostname, some clients were relying on this. This is now optional.

1.2.11 (2017-7-21)

  • Fix for OSX binding to illegal local IP range (Thanks to Gavin Bisesi)
  • Setup and Py3k fixes for pytest-profiling (Thanks to xoviat)
  • We no longer try and bind port 5000 when reserving a local IP host, as someone could have bound it to
  • Fix for #46 sourcing gprof2dot when the local venv has not been activated

1.2.10 (2017-2-23)

  • Handle custom Pytest test items in pytest-webdriver

1.2.9 (2017-2-23)

  • Add username into mongo server fixture tempdir path to stop collisions on shared multiuser filesystems

1.2.8 (2017-2-21)

  • Return function results in

1.2.7 (2017-2-20)

  • More handling for older versions of
  • Allow virtualenv argument passing in pytest-virtualenv

1.2.6 (2017-2-16 )

  • Updated devpi server server setup for devpi-server >= 2.0
  • Improvements for random port picking
  • HTTPD server now binds to by default to aid Selenium-style testing
  • Updated mongodb server args for mongodb >= 3.2
  • Corrections for mongodb fixture config and improve startup logic
  • Added module-scoped mongodb fixture
  • Handling for older versions of
  • Fix for #40 where tests that chdir break pytest-profiling

1.2.5 (2016-12-09)

  • Improvements for server runner host and port generation, now supports random local IPs
  • Bugfix for RethinkDB fixture config

1.2.4 (2016-11-14)

  • Bugfix for pymongo extra dependency
  • Windows compatibility fix for pytest-virtualenv (Thanks to Jean-Christophe Fillion-Robin for PR)
  • Fix symlink handling for pytest-shutil.cmdline.get_real_python_executable

1.2.3 (2016-11-7)

  • Improve resiliency of Mongo fixture startup checks

1.2.2 (2016-10-27)

  • Python 3 compatibility across most of the modules
  • Fixed deprecated imports (Thanks to Bryan Moscon)
  • Fixed deprecated multicall in pytest-profiling (Thanks to Paul van der Linden for PR)
  • Added devpi-server fixture to create an index per test function
  • Added missing licence file
  • Split up httpd server fixture config so child classes can override loaded modules easier
  • Added ‘preserve_sys_path’ argument to TestServer base class which exports the current python sys.path to subprocesses.
  • Updated httpd, redis and jenkins runtime args and paths to current Ubuntu spec
  • Ignore errors when tearing down workspaces to avoid race conditions in ‘shutil.rmtree’ implementation

1.2.1 (2016-3-1)

  • Fixed pytest-verbose-parametrize for latest version of py.test

1.2.0 (2016-2-19)

  • New plugin: git repository fixture

1.1.1 (2016-2-16)

  • pytest-profiling improvement: escape illegal characters in .prof files (Thanks to Aarni Koskela for the PR)

1.1.0 (2016-2-15)

  • New plugin: devpi server fixture
  • pytest-profiling improvement: overly-long .prof files are saved as the short hash of the test name (Thanks to Vladimir Lagunov for PR)
  • Changed default behavior of to not use a subshell for security reasons
  • Corrected method to handle arguments the same as the parent method
  • Removed deprecated ‘–distribute’ from virtualenv args

1.0.1 (2015-12-23)

  • Packaging bugfix

1.0.0 (2015-12-21)

  • Initial public release

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Filename, size & hash SHA256 hash help File type Python version Upload date
pytest_virtualenv-1.3.0-py2.7.egg (7.5 kB) Copy SHA256 hash SHA256 Egg 2.7 Mar 8, 2018
pytest_virtualenv-1.3.0-py2-none-any.whl (11.6 kB) Copy SHA256 hash SHA256 Wheel py2 Mar 8, 2018
pytest-virtualenv-1.3.0.tar.gz (12.5 kB) Copy SHA256 hash SHA256 Source None Mar 8, 2018

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