Coverage reports uploaded successfully from Travis, but we get an error on Codecov

Description

About 5 days ago we started seeing our coverage reports failing to be parsed by Codecov via travis.

Here is a build where the report was successfully uploaded and parsed:

https://travis-ci.org/django-oscar/django-oscar/jobs/567371472

And here is one where a report is uploaded, but codecov reports an error:

https://travis-ci.org/django-oscar/django-oscar/jobs/571690417

The versions of coverage and codecov used on both builds are identical, as is the project structure. We’ve tried all sorts of things to try and work out what the issue is, without success. The “common issues” - things like paths - seem unlikely given that the project structure hasn’t changed.

I’ve run codecov --dump (see https://travis-ci.org/django-oscar/django-oscar/jobs/571663396 for example) and a report is being generated correctly, and is uploaded to codecov. Is it possible there is a bug in how it is processing?

Repository