6. use-coveralls-to-monitor-test-coverage

Date: 2020-10-09

Status

Accepted

Context

We want to keep our test coverage as high as possible without having to run manual checks as these take time and are easy to forget.

Decision

Use Simplecov with RSpec to monitor coverage changes on every test run

Consequences

Simplecov is not dependent on a third-party service such as Coveralls.io
Simplecov can be used on private or public Github repositories
Being part of the test suite allows feedback to be providing locally to give feedback soon
Being part of the test suite allows pull requests to automatically be marked as failed and block merging of new code that introduces gaps
We have to choose a coverage threshold to return an exit code in order to block deploys. The right default value is a matter of opinion however teams can easily change it
Not using a service like Coveralls means we won't have their features like coverage over time, badges, notifications etc