Code Coverage Between Branches

If you need to find code coverage between multiple branches, try the following

Generate the Coverage Report

pytest --cov --cov-report=xml

Install diff-cover

pip install diff_cover

Run diff-cover in your CLI, to see that it is installed properly.

NOTE: If it doesn’t show up for you, try the steps here Access PIP Installed CLI Tools.

Determine the Commit on the Branch You want

You’ll want to go to the branch you want to compare the current branch with. So once you find the commit, and assuming that commit is 3a8c6e0, run the following:

diff-cover ./coverage.xml --compare-branch=3a8c6e0

You should see something like this:

-------------
Diff Coverage
Diff: 3a8c6e0...HEAD, staged and unstaged changes
-------------
my_app/core/utils.py (66.7%): Missing lines 178,180,196,198
my_app/int/utils.py (85.7%): Missing lines 706
my_app/notify/email_utils.py (86.4%): Missing lines 91,114,157,160-161,164,167-168,175
my_app/notify/utils.py (100%)
my_app/api/utils.py (100%)
my_app/runbook/tasks.py (70.0%): Missing lines 710-713,721,728
my_app/runbook/utils.py (100%)
my_app/rest/tasks.py (100%)
my_app/rest/utils.py (100%)
my_app/life/serializers.py (100%)
my_app/life/tasks.py (100%)
my_app/life/utils.py (77.8%): Missing lines 792-793,800-805
my_app/life/views.py (100%)
my_app/web/utils.py (100%)
-------------
Total:   236 lines
Missing: 28 lines
Coverage: 88%
-------------

Get it Quickly

Run the following if you want to quickly get the code coverage of the new code you’re adding between your branch and the latest on master, without doing much work:

diff-cover ./coverage.xml --compare-branch=$(git for-each-ref --sort=-committerdate refs/heads/master | cut -f 1 -d ' ')

Furthermore, you can add an alias to bash so you don’t have to type this everytime.

To do this, run:

alias newcodecov="diff-cover ./coverage.xml --compare-branch=$(git for-each-ref --sort=-committerdate refs/heads/master | cut -f 1 -d ' ')"