Codecov drops when paralelizing with Heroku CI


Hey everyone,

We recently switched our Ruby on Rails app CI from Codeship to Heroku CI.

We used Codeship with 2 concurrent servers who were running parallel tests. Now, we’re using Heroku CI with 6 concurrent servers and no parallel testing.

When making the change, our displayed coverage on Codecov dropped significantly from 80% to 40. I’m guessing some of the servers are not being taken into account, or not loading properly, but all dynos show the Simplecov output saying the coverage stats were uploaded.

I’m kinda lost as to why this would happen - is there a way to check how the codecov report was written? Each call to the Codecov API has its own ID, is there a way to see which IDs are taken into account in a Codecov report?