I'm facing a similar issue - more generally I would expect this tool to not change formatting whatsoever. Going for prettier formatting might clash with other formatters (or configurations) used elsewhere.

I'm encountering the following specific unexpected reformatting:

  example: >
-   sit amet justo donec enim diam vulputate ut pharetra sit amet aliquam id diam
-   maecenas ultricies mi eget mauris pharetra et ultrices neque ornare aenean
+   sit amet justo donec enim diam vulputate ut pharetra sit amet aliquam id diam maecenas ultricies mi eget mauris pharetra et ultrices neque ornare aenean

more generally I would expect this tool to not change formatting whatsoever.

I agree. 🙂

Unfortunately this is a side effect of parsing the YAML file, then serializing it again. We could try parsing to get the data, then using search + replace on the source file to maintain formatting but that could be brittle.

If anyone wants to try raising a PR with that approach to preserve formatting, I'd be happy to review