Coverage.py warning: No data was collected. (no-data-collected)
PythonDjangoPytestcoverage.pyTest CoveragePython Problem Overview
I am trying to find the coverage using coverage module for a django project but gets
Coverage.py warning: No data was collected. (no-data-collected)
My project folder has src and tests folders.
When I run
coverage run -m pytest && coverage report
It produces a report with 100% coverage with the list of files inside the tests folder. Whereas when I run
coverage run --source=src -m pytest && coverage report
it says
Coverage.py warning: No data was collected. (no-data-collected)
No data to report.
When I try to give the source=src or include=src in the .coveragerc also the same warning occurs. The tests passes for all the above cases.
I want the coverage of the src folder. Is it because I am missing some path setting?
Python Solutions
Solution 1 - Python
coverage (used by pytest-cov) needs the tests folder to contain an __init__.py before it will collect any data.
I added __init__.py to the tests folder and then coverage collected the data as expected.
Refer to http://thomas-cokelaer.info/blog/2017/01/pytest-cov-collects-no-data-on-travis/
Solution 2 - Python
I had the same issue and the problem was with the path I was running the tests.
What is working now:
Structure
~/Projects/ProjectName
├── manage.py
├── tests
├── src
│ ├── app_one
├── .coveragerc
Command:
~/Projects/ProjectName$ coverage run manage.py test
and my .coveragerc:
[run]
include = */src/*
omit = *migrations*, *tests*
plugins = django_coverage_plugin
Solution 3 - Python
The problem is that you're not specifying which dir to get coverage from.
You can specify that in the .coveragerc file or on the command line:
pytest tests -v --cov-report term --cov-report html:htmlcov --cov-report xml --cov-fail-under=90 --cov=<the-dir-to-colect-coverage-from>
If you desire you can only execute pytest tests and add pytest args on pytest.ini at your project root:
[pytest]
addopts = -v --cov-report term --cov-report html:htmlcov --cov-report xml --cov-fail-under=<coverage-percentage-desired> --cov=<the-dir-to-colect-coverage-from>
Bonus:
If you want to omit files from the coverage you can add a .coveragerc file on your project root:
[run]
omit =
# omit everything in the folder
proj-ab/api/confs/
# omit file
proj-ab/models/file-not-covered.py
Requirements:
On these examples I'm using requirements: pytest==4.6.2 and pytest-cov==2.7.1
Solution 4 - Python
I had the same issue and the above answers did not fully solve it. It turns out you need to have __init__.py was in every subdirectory that has a test.
Solution 5 - Python
if you need to use 'source' in your .coveragerc, you can write as below
[run]
source = src
omit = *migrations*, *tests*
plugins = django_coverage_plugin
Solution 6 - Python
I encountered this error with tox:
Coverage.py warning: No data was collected. (no-data-collected)
My configuration performs an install of the module and tests that rather than the source code. However, test discovery was finding a module that I had named test_*.py in my app package, causing PYTHONPATH confusion and resulting in failure to collect coverage details. Renaming the module to not start with test_ resolved the issue.