How to exclude whitespace only changes from codecov diff coverage?

We started to use codecov.io as a pull request checker to ensure a minimum test coverage on changes merged. As we have a legacy code base we cannot put overall thresholds very high but want to do this on diff to make sure even new code is well tested.

Also formatting is not always right and now it happens a change containing a small change but also additional reformatting makes codecov assuming a large change which has a bad coverage.

Can I make codecov to check only that part of diff which is not whitespace only? I know github, which is our private repo, can do this by adding a w=1 query param but no clue how to make codecov use that.