On Thu, Jun 22, 2017 at 02:44:58PM +0200, Simon Ruderich wrote: > I'm using Git 2.13.1 (from the Debian sid repository) and noticed > the following issue when upgrading. > > $ git diff --compaction-heuristic > error: invalid option: --compaction-heuristic > > $ git diff --cached --compaction-heuristic > usage: git diff [<options>] [<commit> [<commit>]] [--] [<path>...] > > I know that --compaction-heuristic is no longer supported but I > was using it an alias and was confused that I got no proper error > message warning me which option was wrong. > > It seems to happen for any invalid option which is used in > combination with --cached or --staged.
The diff command splits off into several sub-functions based on whether we're doing an index-to-file diff, an index-to-tree diff, etc. It looks like builtin_diff_files() and builtin_diff_index() just handle this case differently. Probably both should issue an error() mentioning the unknown option _and_ call usage(). I started on a patch, but maybe this would be good micro-project for somebody wanting to get their feet wet with contributing to Git. Bonus points for checking the other functions (builtin_diff_blobs, builtin_diff_tree, builtin_diff_b_f) and making sure they all give appropriate messages when showing the usage string. -Peff
