Py.test Virtualenv Fixture

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.

Installation

Install using your favourite package installer:

    pip install pytest-virtualenv
    # or
    easy_install pytest-virtualenv

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

    pytest_plugins = ['pytest_virtualenv']

Configuration

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 path.py see https://pathpy.readthedocs.io/

def test_virtualenv(virtualenv):
    # the 'virtualenv' attribute is a `path.py` object for the root of the virtualenv
    dirnames = virtualenv.virtualenv.dirs()
    assert {'bin', 'include', 'lib'}.intersection(set(dirnames))
    
    # the 'python' attribute is a `path.py` 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 [i.name 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 setup.py 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 setup.py 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 = virtualenv.run("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.install_package(coverage)
    virtualenv.run_with_coverage(["my_entry_point", "--arg1", "--arg2"])

Changelog

1.8.0 (2024-10-??)

• All: Drop support for Python 2 and <3.6, removing compatibility code.
• All: Use stdlib unittest.mock instead of mock package.
• All: Removed usage of path.py and path in favour of pathlib. #174 #224
• pytest-devpi-server: Run devpi-init for initialisation. #179
• pytest-server-fixtures: BREAKING CHANGE: Removed RethinkDB support, as the project is no longer maintained.
• pytest-server-fixtures: Allowed passing through HTTP headers to the server. #149
• pytest-server-fixtures: Fixed threading log debug messages. #146
• pytest-server-fixtures: Removed usage of deprecated Thread.setDaemon. #202
• pytest-server-fixtures: Explicitly close initial Mongo client. #198
• pytest-server-fixtures: Don't use context manager for CREATE DATABASE #186
• pytest-shutil: Removed contextlib2 requirement. #144
• pytest-shutil: Fixed forcing color through termcolor. #217
• pytest-shutil: Replaced deprecated imp module #219
• pytest-profiling: Added support to hide/show the full path of file. #95
• pytest-profiling: Fixed SVG file generation on Windows. #93
• pytest-profiling: Remove pinning of more-itertools. #194
• pytest-profiling: Add support to define element number for print_stats() #96
• pytest-profiling: Fix mock in test_writes_summary #223
• pytest-virtualenv: Modernised package. #188 #185 #182 #163
• pytest-virtualenv: Fixed virtualenv creation on Windows. #142
• pytest-virtualenv: Added delete_workspace parameter to VirtualEnv. #195
• pytest-virtualenv: Removed extras_require. #240
• ci: Remove usage of deprecated distutils. #189
• ci: Disabled jenkins server tests on CircleCI to improve build time.
• ci: Fixed collections import for py 3.11 compatibility #222

1.7.1 (2019-05-28)

• pytest-profiling: Fix pytest-profiling to profile fixtures. #48
• pytest-devpi-server: Fixed Python 3.4 support updating "ruamel.yaml" requirements. #138
• ci: Added PYTEST_DONT_REWRITE in order to suppress module already imported. #123

1.7.0 (2019-02-21)

• All: Support pytest >= 4.0.0
• All: Support Python 3.7
• pytest-server-fixtures: if host not defined on your machine, default to localhost
• pytest-server-fixture: Pin to rethinkdb < 2.4.0 due to upstream API changes
• pytest-verbose-parametrize: Add support for revamped marker infrastructure
• pytest-verbose-parametrize: Fix integration tests to support pytest >= 4.1.0
• pytest-virtualenv: Add virtualenv as install requirement. Fixes #122
• pytest-webdriver: Fix RemovedInPytest4Warning using getfixturevalue
• circleci: Fix checks by skipping coverall submission for developer without push access
• wheels: Generate universal wheels installable with both python 2.x and 3.x
• dist: Remove support for building and distributing *.egg files
• VagrantFile: Install python 3.7 and initialize python 3.7 by default
• Fix DeprecationWarning warnings using "logger.warning()" function

1.6.2 (2019-02-21)

• pytest-server-fixtures: suppress stacktrace if kill() is called
• pytest-server-fixtures: fix random port logic in TestServerV2

1.6.1 (2019-02-12)

• pytest-server-fixtures: fix exception when attempting to access hostname while server is not started

1.6.0 (2019-02-12)

• pytest-server-fixtures: added previously removed TestServerV2.kill() function
• pytest-profiling: pin more-itertools==5.0.0 in integration tests, as that's a PY3 only release

1.5.1 (2019-01-24)

• pytest-verbose-parametrize: fixed unicode parameters when using @pytest.mark.parametrize

1.5.0 (2019-01-23)

• pytest-server-fixtures: made postgres fixtures and its tests optional, like all other fixtures
• pytest-server-fixtures: reverted a fix for pymongo deprecation warning, as this will break compatibility with pymongo 3.6.0
• pytest-server-fixtures: dropped RHEL5 support in httpd

1.4.1 (2019-01-18)

• pytest-server-fixtures: server fixture binary path specified in ENV now only affect server class 'thread'

1.4.0 (2019-01-15)

• Fixing python 3 compatibility in Simple HTTP Server fixture
• Fixed broken tests in pytest-profiling
• Pinned pytest<4.0.0 until all deprecation warnings are fixed.
• pytest-webdriver: replaced deprecated phantomjs with headless Google Chrome.
• Add Vagrantfile to project to make test environment portable.
• Add .editorconfig file to project.
• pytest-server-fixtures: add TestServerV2 with Docker and Kubernetes support.
• pytest-server-fixtures: fix for an issue where MinioServer is not cleaned up after use.
• pytest-server-fixtures: fix deprecation warnings when calling pymongo.
• pytest-server-fixtures: close pymongo client on MongoTestServer teardown.
• pytest-server-fixtures: upgrade Mongo, Redis and RethinkDB to TestServerV2.
• coveralls: fix broken coveralls

1.3.1 (2018-06-28)

• Use pymongo list_database_names() instead of the deprecated database_names(), added pymongo>=3.6.0 dependency

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 0.0.0.0
• 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 shutil.run.run_as_main

1.2.7 (2017-2-20)

• More handling for older versions of path.py
• 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 0.0.0.0 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 path.py
• 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 Path.py 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 workspace.run() to not use a subshell for security reasons
• Corrected virtualenv.run() method to handle arguments the same as the parent method workspace.run()
• Removed deprecated '--distribute' from virtualenv args

1.0.1 (2015-12-23)

• Packaging bugfix

1.0.0 (2015-12-21)

• Initial public release