GitLab test coverage visualization is not working on a simple example

Question

I have created a very simple example: https://gitlab.com/mvfwd/gitlab-coverage.

Unfortunately gitlab does not show Cobertura coverage visualisation.

Here is my .gitlab-ci.yml:

image: python:3

stages:
- test

coverage:
  stage: test
  script:
  - pip install coverage
  - coverage run ./main.py
  - coverage report -m
  - coverage xml
  artifacts:
    paths:
    - ./coverage.xml
    reports:
      cobertura: ./coverage.xml
  only:
  - master

In logs I can see that coverage report is uploaded (link):

$ coverage run ./main.py
..
----------------------------------------------------------------------
Ran 2 tests in 0.001s
OK
$ coverage report -m
Name      Stmts   Miss  Cover   Missing
---------------------------------------
main.py      26     12    54%   9-14, 20-25
---------------------------------------
TOTAL        26     12    54%
$ coverage xml
Uploading artifacts for successful job
00:03
Uploading artifacts...
./coverage.xml: found 1 matching files and directories 
Uploading artifacts as "archive" to coordinator... ok  id=1450561054 responseStatus=201 Created token=eZqc9KYb
Uploading artifacts...
./coverage.xml: found 1 matching files and directories 
Uploading artifacts as "cobertura" to coordinator... ok  id=1450561054 responseStatus=201 Created token=eZqc9KYb
Cleaning up file based variables
00:00
Job succeeded

What am I doing wrong?

Answer 1

I have filed an issue and solution was found. Here is the recap:

• I understood the feature wrong, it works only for MR changes, not on regular commits or in file explorer
• I missed that recently there was a rename from master to main, documenation examples were not updated and I copied that to my .gitlab-ci.yml, which prevented autostarting pipelines on commit