How to evaluate the coverage of a django test suite

I am using this recipe to estimate the coverage of the test suites arounds my django's projects.

Software Prerequisites

In order to follow this recipe you will need to have the following software installed :

• Django
• python (obviously)
• coverage.py

I will not explain how to get the first 2 items of this list installed since if you are reading this I am assuming that you are familiar with them. "Coverage" is a bit different, python package index make installing this component a piece of cake.

# easy_install coverage

Usage of coverage with django test suite

This presentation give a recipe to evaluate the coverage of your test suite. I found this page useful to understand how to use it. If you are looking for a project to test this recipe on you can checkout "django-survey". The 3 lines below is all you need to get a report on the coverage of your test suite.

# coverage.py -e                            (1)
# coverage.py -x manage.py test survey      (2)
# coverage.py -r -m >report.txt             (3)

The first line erases collected coverage data, the second executes the module and collect the coverage data, the third line reports on the statement coverage for the given files and show line numbers of the statements that weren't executed.

Then you need to analyze the file called "report.txt" and extract the information usefull to your project. In our case all the files located in django-survey :

Name 
------------------------------------------------------------------------------------------------------------------------------------------------
__init__                                                                                                               0      0   100%
[...]
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\__init__                                              0      0   100%
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\forms                                               172    117    68%   32, 47-49, 56, 74-86, 96, 107, 117-120, 126-136, 139-145, 147-159, 212, 226-227, 230
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\models                                              157    142    90%   28-29, 70, 82-83, 88-89, 102-104, 109, 126, 159, 211, 236
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\templatetags\__init__                                 0      0   100%
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\templatetags\survey                                  10      7    70%   8, 16-17
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\tests\__init__                                        2      2   100%
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\tests\test_images                                     1      1   100%
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\tests\test_models                                     1      1   100%
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\tests\test_urls                                       1      1   100%
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\urls                                                  6      6   100%
c:\yml\_myscript_\dj_things\web_development\django-survey\survey\views                                               183    126    68%   47, 54-65, 79-83, 90, 94, 96, 124-125, 150-151, 157-158, 183-186, 230-231, 246, 261-263, 280-281, 311-313, 328, 341-342, 359-360, 379, 419-425, 444-456, 462-474
[...]
manage                                                                                                                13      9    69%   10-13
management\__init__                                                                                                    0      0   100%
settings                                                                                                              31     31   100%
urls                                                                                                                   4      4   100%