Metadata-Version: 1.1
Name: pyfakefs
Version: 3.4
Summary: pyfakefs implements a fake file system that mocks the Python file system modules.
Home-page: http://pyfakefs.org
Author: John McGehee
Author-email: pyfakefs@johnnado.com
License: UNKNOWN
Description-Content-Type: UNKNOWN
Description: pyfakefs

        ========

        

        pyfakefs implements a fake file system that mocks the Python file system

        modules. Using pyfakefs, your tests operate on a fake file system in

        memory without touching the real disk. The software under test requires

        no modification to work with pyfakefs.

        

        pyfakefs works with Linux, Windows and MacOS.

        

        Documentation

        -------------

        

        This file provides general usage instructions for pyfakefs. There is

        more:

        

        -  The documentation at `GitHub

           Pages: <http://jmcgeheeiv.github.io/pyfakefs>`__

        

           -  The `Release

              documentation <http://jmcgeheeiv.github.io/pyfakefs/release>`__

              contains usage documentation for pyfakefs and a description of the

              most relevent classes, methods and functions for the last version

              released on PyPi

           -  The `Development

              documentation <http://jmcgeheeiv.github.io/pyfakefs/master>`__

              contains the same documentation for the current master branch

           -  The `Release 3.3

              documentation <http://jmcgeheeiv.github.io/pyfakefs/3.3>`__

              contains usage documentation for the last version of pyfakefs

              supporting Python 2.6, and for the old-style API (which is still

              supported but not documented in the current release)

        

        -  The `Release

           Notes <https://github.com/jmcgeheeiv/pyfakefs/blob/master/CHANGES.md>`__

           show a list of changes in the latest versions

        

        Linking to pyfakefs

        ~~~~~~~~~~~~~~~~~~~

        

        In your own documentation, please link to pyfakefs using the canonical

        URL http://pyfakefs.org. This URL always points to the most relevant top

        page for pyfakefs.

        

        Usage

        -----

        

        There are several approaches to implementing tests using pyfakefs.

        

        Automatically find and patch

        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~

        

        | The first approach is to allow pyfakefs to automatically find all real

          file functions and modules, and stub these out with the fake file

          system functions and modules.

        | This is explained in the pyfakefs wiki page `Automatically find and

          patch file functions and

          modules <http://jmcgeheeiv.github.io/pyfakefs/master/autopatch.html>`__

          and demonstrated in files ``example.py`` and ``example_test.py``.

        

        Patch using the PyTest plugin

        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

        

        If you use `PyTest <https://doc.pytest.org>`__, you will be interested

        in the PyTest plugin in pyfakefs. This automatically patches all file

        system functions and modules in a manner similar to the `automatic find

        and patch

        approach <http://jmcgeheeiv.github.io/pyfakefs/master/autopatch.html>`__

        described above.

        

        The PyTest plugin provides the ``fs`` fixture for use in your test. For

        example:

        

        .. code:: python

        

            def my_fakefs_test(fs):

                # "fs" is the reference to the fake file system

                fs.create_file('/var/data/xx1.txt')

                assert os.path.exists('/var/data/xx1.txt')

        

        Patch using fake_filesystem_unittest.Patcher

        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

        

        If you are using other means of testing like

        `nose <http://nose2.readthedocs.io>`__, you can do the patching using

        ``fake_filesystem_unittest.Patcher`` - the class doing the the actual

        work of replacing the filesystem modules with the fake modules in the

        first two approaches.

        

        The easiest way is to just use ``Patcher`` as a context manager:

        

        .. code:: python

        

            from fake_filesystem_unittest import Patcher

        

            with Patcher() as patcher:

               # access the fake_filesystem object via patcher.fs

               patcher.fs.create_file('/foo/bar', contents='test')

        

               # the following code works on the fake filesystem

               with open('/foo/bar') as f:

                   contents = f.read()

        

        You can also initialize ``Patcher`` manually:

        

        .. code:: python

        

            from fake_filesystem_unittest import Patcher

        

            patcher = Patcher()

            patcher.setUp()     # called in the initialization code

            ...

            patcher.tearDown()  # somewhere in the cleanup code

        

        Patch using unittest.mock (deprecated)

        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

        

        You can also use ``mock.patch()`` to patch the modules manually. This

        approach will only work for the directly imported modules, therefore it

        is not suited for testing larger code bases. As the other approaches are

        more convenient, this one is considered deprecated. You have to create a

        fake filesystem object, and afterwards fake modules based on this file

        system for the modules you want to patch.

        

        The following modules and functions can be patched:

        

        -  ``os`` and ``os.path`` by ``fake_filessystem.FakeOsModule``

        -  ``io`` by ``fake_filessystem.FakeIoModule``

        -  ``pathlib`` by ``fake_pathlib.FakePathlibModule``

        -  build-in ``open()`` by ``fake_filessystem.FakeFileOpen``

        

        .. code:: python

        

        

               import pyfakefs.fake_filesystem as fake_fs

        

               # Create a faked file system

               fs = fake_fs.FakeFilesystem()

        

               # Do some setup on the faked file system

               fs.CreateFile('/foo/bar', contents='test')

        

               # Replace some built-in file system related modules you use with faked ones

        

               # Assuming you are using the mock library to ... mock things

               try:

                   from unittest.mock import patch  # In Python 3, mock is built-in

               except ImportError:

                   from mock import patch  # Python 2

        

               # Note that this fake module is based on the fake fs you just created

               os = fake_fs.FakeOsModule(fs)

               with patch('mymodule.os', os):

                   fd = os.open('/foo/bar', os.O_RDONLY)

                   contents = os.read(fd, 4)

        

        Installation

        ------------

        

        Compatibility

        ~~~~~~~~~~~~~

        

        pyfakefs works with CPython 2.7, 3.3 and above, on Linux, Windows and

        OSX (MacOS), and with PyPy2 and PyPy3.

        

        pyfakefs works with `PyTest <http://doc.pytest.org>`__ version 2.8.6 or

        above.

        

        pyfakefs will not work with Python libraries that use C libraries to

        access the file system. This is because pyfakefs cannot patch the

        underlying C libraries’ file access functions–the C libraries will

        always access the real file system. For example, pyfakefs will not work

        with ```lxml`` <http://lxml.de/>`__. In this case ``lxml`` must be

        replaced with a pure Python alternative such as

        ```xml.etree.ElementTree`` <https://docs.python.org/3/library/xml.etree.elementtree.html>`__.

        

        PyPi

        ~~~~

        

        `pyfakefs is available on

        PyPi <https://pypi.python.org/pypi/pyfakefs/>`__.

        

        Development

        -----------

        

        Continuous integration

        ~~~~~~~~~~~~~~~~~~~~~~

        

        pyfakefs is currently automatically tested: \* On Linux, with Python

        2.7, 3.3 and above using

        `Travis <https://travis-ci.org/jmcgeheeiv/pyfakefs>`__ \* On MacOS, with

        Python 2.7 and 3.6, also using

        `Travis <https://travis-ci.org/jmcgeheeiv/pyfakefs>`__. The Linux/MacOS

        build is currently |Build Status|. \* On Windows, with Python 2.7, 3.4

        and above using

        `Appveyor <https://ci.appveyor.com/project/jmcgeheeiv/pyfakefs>`__. The

        Windows build is currently |Build status|.

        

        Running pyfakefs unit tests

        ~~~~~~~~~~~~~~~~~~~~~~~~~~~

        

        pyfakefs unit tests are available via two test scripts:

        

        .. code:: bash

        

            $ python all_tests.py

            $ py.test pytest_plugin_test.py

        

        These scripts are called by ``tox`` and Travis-CI. ``tox`` can be used

        to run tests locally against supported python versions:

        

        .. code:: bash

        

            $ tox

        

        Contributing to pyfakefs

        ~~~~~~~~~~~~~~~~~~~~~~~~

        

        We always welcome contributions to the library. Check out the

        `Contributing

        Guide <https://github.com/jmcgeheeiv/pyfakefs/blob/master/CONTRIBUTING.md>`__

        for more information.

        

        History

        -------

        

        pyfakefs.py was initially developed at Google by Mike Bland as a modest

        fake implementation of core Python modules. It was introduced to all of

        Google in September 2006. Since then, it has been enhanced to extend its

        functionality and usefulness. At last count, pyfakefs is used in over

        2,000 Python tests at Google.

        

        Google released pyfakefs to the public in 2011 as Google Code project

        `pyfakefs <http://code.google.com/p/pyfakefs/>`__: \* Fork

        `jmcgeheeiv-pyfakefs <http://code.google.com/p/jmcgeheeiv-pyfakefs/>`__

        added `direct support for unittest and

        doctest <../../wiki/Automatically-find-and-patch-file-functions-and-modules>`__

        \* Fork

        `shiffdane-jmcgeheeiv-pyfakefs <http://code.google.com/p/shiffdane-jmcgeheeiv-pyfakefs/>`__

        added further corrections

        

        After the `shutdown of Google

        Code <http://google-opensource.blogspot.com/2015/03/farewell-to-google-code.html>`__

        was announced, `John McGehee <https://github.com/jmcgeheeiv>`__ merged

        all three Google Code projects together `here on

        GitHub <https://github.com/jmcgeheeiv/pyfakefs>`__ where an enthusiastic

        community actively supports, maintains and extends pyfakefs.

        

        .. |Build Status| image:: https://travis-ci.org/jmcgeheeiv/pyfakefs.svg

           :target: https://travis-ci.org/jmcgeheeiv/pyfakefs

        .. |Build status| image:: https://ci.appveyor.com/api/projects/status/4o8j21ufuo056873/branch/master?svg=true

           :target: https://ci.appveyor.com/project/jmcgeheeiv/pyfakefs/branch/master

        
Keywords: testing,test,file,os,shutil,glob,mocking,unittest,fakes,filesystem,unit
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Environment :: Console
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Apache Software License
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3.3
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
Classifier: Programming Language :: Python :: 3.6
Classifier: Operating System :: POSIX
Classifier: Operating System :: MacOS
Classifier: Operating System :: Microsoft :: Windows
Classifier: Topic :: Software Development :: Libraries
Classifier: Topic :: Software Development :: Libraries :: Python Modules
Classifier: Topic :: Software Development :: Testing
Classifier: Topic :: System :: Filesystems
