tests/autodiff.py: explicitly only honor feature diffopts This test extension manages the opts it cares about on its own anyway.

cmdutil.changeset_printer: explicitly honor all diffopts This is used in hg log -p so the output is expected to be the same as that of hg diff.

export: explicitly honor all diffopts This is slightly more controversial than diff, but we hope that HGPLAIN=1 covers all the format-breaking ones. A possible alternative here that breaks BC is to honor all opts except the whitespace ones.

webcommands.annotate: explicitly only honor whitespace diffopts The whitespace ones are the only ones the annotate logic cares about anyway, so there's no visible impact.

filectx.parents: filter nullrev parent sooner We are going to introduce a linkrev-correction phases when computing parents. It will be more convenient to have the nullid parent filtered out earlier. I had to make a minimal adjustment to the rename handling logic to keep it functional. That logic have been documented in the process since it took me some time to check all the cases out.

context: catch FilteredRepoLookupError instead of RepoLookupError Now that we have a more specialised exception, lets use it when we meant to catch the more specialised case.