Re: git-diff-tree rename detection for single file

David Ho [off-list ref] writes:

I have a small suggestion to make the diff of a renamed file a bit
more meaningful.  I have a file that is renamed-edited and commited. 
git-diff-tree -M -p <commit> shows one result and git-diff-tree -M -p
<commit> <filename> shows another.  If they both show a rename
occurred then I think the single file git-diff-tree will be more
useful.

Sorry, this has vetoed by Linus long time ago.  The <filename>
restricts the paths being passed to the diff machinery upfront,
so once you say <filename>, the rename detection will see only
that path and nothing else to compare and guess which other file
that file in question is a copy of.