Is there a way to add coverage report to gitlab?

I fear there is still no easy way to integrate code coverage reports but Gitlab now supports (since Version 8.0 integrated) build jobs for your code. Unfortunately you have to implement your solution by writing a custom .gitlab-ci.yml to run your coverage tests. For viewing the reports, you can specify the generated "artifacts" or publish them on gitlab pages.

For more information, see here: https://about.gitlab.com/gitlab-ci/

Additionally you can parse a text output to display a short code coverage report:

• (Enable builds and output test coverage)
• Go to "Project Settings" -> Builds
• Add to "Test coverage parsing" a regular expression (examples below, simplecov included)

See Publish Code Coverage Report with GitLab Pages