Error: Cannot convert undefined or null to object

[GaboFDC]

I just setup the action but I'm getting the error:

Not sure whats the problem, I thought it may be because there is no diff at the moment, but I saw there is a test for that, so not sure where the error may be.

[steventux]

I think this is to do with not generating branch coverage using Simplecov, there seems to be an expectation that coverage.branches is an object here: https://github.com/kzkn/simplecov-resultset-diff-action/blob/main/src/simplecov.ts#L79

eg.

Simplecov.start 'rails' do
  enable_coverage :branch
end

Adding the above fixed this error for me.

[brunocalmels]

I'm facing the same issue. I added branch coverage but that did't solve the issue.

[instrumentl707]

@brunocalmels I have the same issue - did you manage to resolve it?

[jverce]

The solution provided by @steventux worked for me, but only after pushing those changes to the base branch. Given that this action needs to measure the test coverage in both the head and the base Git branches, you need to have branch coverage in both Git branches.

In other words, make sure you have enable_coverage :branch in your base branch, and only then run this Github action in a pull request.