Re: [PATCH 2/3] Teach git diff-tree --stdin to diff trees

Karl Hasselström [off-list ref] writes:

In addition to accepting lines with one or more commits, it now
accepts lines with precisely two trees.

Hmm, slightly dissapointed (I actually was hoping you would also handle
more than two trees and run -m or -c or --cc on them).

"On the command line, you can give exactly two trees, not three nor one;
this two-tree form is now also supported in --stdin mode." --- that
justfication sounds like a good one (and that is why my dissapointment is
only "slight").

But the following two sentences are a bit confusing, especially it is
unclear what "This" refers to in the last sentence.

When diffing trees, the -m, -s, -v, --pretty, --abbrev-commit,
--encoding, --no-commit-id, -c, --cc, and --always options are
ignored, since they do not apply to trees. This is the same behavior
you get when specifying two trees on the command line instead of with
--stdin.

Perhaps swap the sentences in the log message like this?

  When feeding trees on the command line, you can give exactly two trees,
  not three nor one; --stdin now supports this "two tree" form on its
  input, in addition to accepting lines with one or more commits.

  When diffing trees (either specified on the command line or from the
  standard input), the -m, -s, -v, --pretty, --abbrev-commit, --encoding,
  --no-commit-id, -c, --cc, and --always options are ignored, since they
  do not apply to trees.

Thanks, now we can update that documentation change.