I know this has been already discussed in #316, #144 and travis-ci/travis-ci#9248

But it's really annoying and completely beats the purpose of automated writing to the file if it destroys the formatting in the process.

Since it only has to check if the given field is present and overwrite it, or if not present append the field to the end of file, I don't think this needs a full parser reimplementation, and probably should be handled as its own case.

Let me now if this sounds reasonable to you.