Maybe the problem isn't so much the text representation but the absence of a canonical representation. If there was a well define canonical representation for any program then it would be trivial to view and edit it in my prefered style without messing up the diffs in the repo.

Code formatters help, some more than others but most are far from producing a canonical format. This means that I either need to edit in the projects prefered style or have my editor carefully track which sections I haven't modified and be sure to write them back exactly as the originally appeared.