Yes Junichi, this new release explicitely deprecates dashed form of git commands, as they will probably go away from the $PATH for many good reasons:

  • the shell completions are way better hence the need for git-* being in /usr/bin has gone for quite some time now;
  • the amount of git-<tab> completions scares the hell out of new users, let's do like bzr (that has more commands than git, and many undocumented ones unlike git whatever they say, they just hide them) and don't publicize our guts for nothing (though everything will always remain documented);
  • there are some issues with dashed commands being in the $PATH that generate misfeatures, for example if you have a ssh command in $HOME/bin it won't be picked because git puts the path where dashed command live front (to avoid versions mismatch) hence you pick /usr/bin/ssh again (hi dato !);
  • we may not have a 1:1 relation between git commands and dashed version for the rest of git's life;
  • aliases (that you can configure in $HOME/.gitconfig already don't work with the dashed form for obvious reasons, so it's better not using the dash for consistency's sake.

So we gave our users a pretty good timeframe to adapt their scripts, hence the deprecation notice.

Also note that best practices about scripting are now documented in the gitcli(5) man page I wrote.