Hacking on :mod:`zope.interface`
================================


Getting the Code
################

The main repository for :mod:`zope.interface` is in the Zope Foundation
Github repository:

  https://github.com/zopefoundation/zope.interface

You can get a read-only checkout from there:

.. code-block:: sh

   $ git clone https://github.com/zopefoundation/zope.interface.git

or fork it and get a writeable checkout of your fork:

.. code-block:: sh

   $ git clone git@github.com/jrandom/zope.interface.git

The project also mirrors the trunk from the Github repository as a
Bazaar branch on Launchpad:

https://code.launchpad.net/zope.interface

You can branch the trunk from there using Bazaar:

.. code-block:: sh

   $ bzr branch lp:zope.interface


Working in a ``virtualenv``
###########################

Running the tests
-----------------

If you use the ``virtualenv`` package to create lightweight Python
development environments, you can run the tests using nothing more
than the ``python`` binary in a virtualenv.  First, create a scratch
environment:

.. code-block:: sh

   $ /path/to/virtualenv --no-site-packages /tmp/hack-zope.interface

Next, get this package registered as a "development egg" in the
environment:

.. code-block:: sh

   $ /tmp/hack-zope.interface/bin/python setup.py develop

Finally, run the tests using the build-in ``setuptools`` testrunner:

.. code-block:: sh

   $ /tmp/hack-zope.interface/bin/python setup.py test -q
   running test
   ...
   ----------------------------------------------------------------------
   Ran 2 tests in 0.000s

   OK

The ``dev`` command alias downloads and installs extra tools, like the
:mod:`nose` testrunner and the :mod:`coverage` coverage analyzer:

.. code-block:: sh

   $ /tmp/hack-zope.interface/bin/python setup.py dev
   $ /tmp/hack-zope.interface/bin/nosetests
   running nosetests
   .................................... (lots more dots)
   ----------------------------------------------------------------------
   Ran 707 tests in 2.166s

   OK

If you have the :mod:`coverage` package installed in the virtualenv,
you can see how well the tests cover the code:

.. code-block:: sh

   $ /tmp/hack-zope.interface/bin/nosetests --with coverage
   running nosetests
   .................................... (lots more dots)
   Name                               Stmts   Miss  Cover   Missing
   ----------------------------------------------------------------
   zope.interface                        30      0   100%   
   zope.interface.adapter               440      0   100%   
   zope.interface.advice                 69      0   100%   
   zope.interface.common                  0      0   100%   
   zope.interface.common.idatetime       98      0   100%   
   zope.interface.common.interfaces      81      0   100%   
   zope.interface.common.mapping         32      0   100%   
   zope.interface.common.sequence        38      0   100%   
   zope.interface.declarations          312      0   100%   
   zope.interface.document               54      0   100%   
   zope.interface.exceptions             21      0   100%   
   zope.interface.interface             378      0   100%   
   zope.interface.interfaces            137      0   100%   
   zope.interface.registry              300      0   100%   
   zope.interface.ro                     25      0   100%   
   zope.interface.verify                 48      0   100%   
   ----------------------------------------------------------------
   TOTAL                               2063      0   100%   
   ----------------------------------------------------------------------
   Ran 707 tests in 2.166s

   OK


Building the documentation
--------------------------

:mod:`zope.interface` uses the nifty :mod:`Sphinx` documentation system
for building its docs.  Using the same virtualenv you set up to run the
tests, you can build the docs:

The ``docs`` command alias downloads and installs Sphinx and its dependencies:

.. code-block:: sh

   $ /tmp/hack-zope.interface/bin/python setup.py docs
   ...
   $ bin/sphinx-build -b html -d docs/_build/doctrees docs docs/_build/html
   ...
   build succeeded.

   Build finished. The HTML pages are in docs/_build/html.

You can also test the code snippets in the documentation:

.. code-block:: sh

   $ bin/sphinx-build -b doctest -d docs/_build/doctrees docs docs/_build/doctest
   ...
   running tests...

   Document: index
   ---------------
   1 items passed all tests:
     17 tests in default
   17 tests in 1 items.
   17 passed and 0 failed.
   Test passed.

   Doctest summary
   ===============
      17 tests
       0 failures in tests
       0 failures in setup code
   build succeeded.
   Testing of doctests in the sources finished, look at the  \
       results in docs/_build/doctest/output.txt.



Using :mod:`zc.buildout`
########################

Setting up the buildout
-----------------------

:mod:`zope.interface` ships with its own :file:`buildout.cfg` file and
:file:`bootstrap.py` for setting up a development buildout:

.. code-block:: sh

   $ /path/to/python2.7 bootstrap.py
   ...
   Generated script '.../bin/buildout'
   $ bin/buildout
   Develop: '/home/jrandom/projects/Zope/BTK/interface/.'
   ...
   Generated script '.../bin/sphinx-quickstart'.
   Generated script '.../bin/sphinx-build'.

Running the tests
-----------------

You can now run the tests:

.. code-block:: sh

   $ bin/test --all
   Running zope.testing.testrunner.layer.UnitTests tests:
     Set up zope.testing.testrunner.layer.UnitTests in 0.000 seconds.
     Ran 702 tests with 0 failures and 0 errors in 0.000 seconds.
   Tearing down left over layers:
     Tear down zope.testing.testrunner.layer.UnitTests in 0.000 seconds.


Using :mod:`tox`
################

Running Tests on Multiple Python Versions
-----------------------------------------

`tox <http://tox.testrun.org/latest/>`_ is a Python-based test automation
tool designed to run tests against multiple Python versions.  It creates
a ``virtualenv`` for each configured version, installs the current package
and configured dependencies into each ``virtualenv``, and then runs the
configured commands.
   
:mod:`zope.interface` configures the following :mod:`tox` environments via
its ``tox.ini`` file:

- The defined Python environments build a ``virtualenv`` with various Python 2,
  Python 3, PyPy 2 and PyPy 3 versions, install :mod:`zope.interface` and
  dependencies, and run the tests via ``python setup.py test -q``.

- The ``coverage`` environment builds a ``virtualenv`` with ``python2.7``,
  installs :mod:`zope.interface` and dependencies, installs
  :mod:`nose` and :mod:`coverage`, and runs ``nosetests`` with statement
  coverage.

- The ``docs`` environment builds a virtualenv with ``python2.7``, installs
  :mod:`zope.interface` and dependencies, installs ``Sphinx`` and
  dependencies, and then builds the docs and exercises the doctest snippets.

This example requires that you have a working ``python2.7`` on your path,
as well as installing ``tox``:

.. code-block:: sh

   $ tox -e py26
   GLOB sdist-make: .../zope.interface/setup.py
   py26 sdist-reinst: .../zope.interface/.tox/dist/zope.interface-4.0.2dev.zip
   py26 runtests: commands[0]
   ...
   ----------------------------------------------------------------------
   Ran 1341 tests in 0.477s

   OK
   ___________________________________ summary ____________________________________
   py26: commands succeeded
   congratulations :)

Running ``tox`` with no arguments runs all the configured environments,
including building the docs and testing their snippets:

.. code-block:: sh

   $ tox
   GLOB sdist-make: .../zope.interface/setup.py
   py26 sdist-reinst: .../zope.interface/.tox/dist/zope.interface-4.0.2dev.zip
   py26 runtests: commands[0]
   ...
   Doctest summary
   ===============
   678 tests
      0 failures in tests
      0 failures in setup code
      0 failures in cleanup code
   build succeeded.
   ___________________________________ summary ____________________________________
   py26: commands succeeded
   py27: commands succeeded
   py32: commands succeeded
   pypy: commands succeeded
   coverage: commands succeeded
   docs: commands succeeded
   congratulations :)


Contributing to :mod:`zope.interface`
#####################################

Submitting a Bug Report
-----------------------

:mod:`zope.interface` tracks its bugs on Github:

  https://github.com/zopefoundation/zope.interface/issues

Please submit bug reports and feature requests there.


Sharing Your Changes
--------------------

.. note::

   Please ensure that all tests are passing before you submit your code.
   If possible, your submission should include new tests for new features
   or bug fixes, although it is possible that you may have tested your
   new code by updating existing tests.

If have made a change you would like to share, the best route is to fork
the Githb repository, check out your fork, make your changes on a branch
in your fork, and push it.  You can then submit a pull request from your
branch:

  https://github.com/zopefoundation/zope.interface/pulls

If you branched the code from Launchpad using Bazaar, you have another
option:  you can "push" your branch to Launchpad:

.. code-block:: sh

   $ bzr push lp:~jrandom/zope.interface/cool_feature

After pushing your branch, you can link it to a bug report on Launchpad,
or request that the maintainers merge your branch using the Launchpad
"merge request" feature.