Function breakdown and Testing Intro
====================================

In the `elex2/ <https://github.com/PythonJournos/refactoring101/tree/master/elex2>`__
directory, we've chopped up the original election\_results.py code into a bunch of functions and turned this code
directory into a package by adding an \_\_init\_\_.py file.

We've also added a suite of tests. This way we can methodically change
the underlying code in later phases, while having greater confidence
that we haven't corrupted our summary numbers.

    **Note**: We can't stress this step enough: Testing existing code is *THE* critical first step in refactoring.

If the code doesn't have tests, write some, at least for the most important bits of logic.
Otherwise you're just `changing shit <http://hamletdarcy.blogspot.com/2009/06/forgotten-refactorings.html>`__.

Fortunately, our code has a suite of `unit
tests <http://docs.python.org/2/library/unittest.html>`__ for name
parsing and, most importantly, the summary logic.

Python has built-in facilities for running tests, but they're a little
raw for our taste. We'll use the
`nose <https://nose.readthedocs.org/en/latest/index.html>`__ library to
more easily run our tests:

.. code:: bash

    nosetests -v tests/test_parser.py
    # or run all tests in the tests/ directory
    nosetests -v tests/*.py

Observations
------------

At a high level, this code is an improvement over *elex1/*, but it could
still be much improved. We'll get to that in Phase 3, when we introduce
`modules <http://docs.python.org/2/tutorial/modules.html>`__ and
`packages <http://docs.python.org/2/tutorial/modules.html#packages>`__.

Questions
---------

-  What is \_\_init\_\_.py and why do we use it?
-  In what order are test methods run?
-  What does the TestCase *setUp* method do?
-  What other TestCase methods are available?

Exercises
---------

-  Install `nose <https://nose.readthedocs.org/en/latest/index.html>`__
   and run the tests. Try breaking a few tests and run them to see the
   results.
-  List three ways this code is better than the previous version; and
   three ways it could be improved.
-  Organize functions in *election\_results.py* into two or more new
   modules. (Hint: There is no right answer here. `Naming things is
   hard <http://martinfowler.com/bliki/TwoHardThings.html>`__; aim for
   directory and file names that are short but meaningful to a normal
   human).