tree b7fdc1790761c3248d94be102a9eee71fa9077a9
parent 20de316e33446f37200e51aa333ba7d824dfd478
author Johannes Schindelin <johannes.schindelin@gmx.de> 1557352361 -0700
committer Junio C Hamano <gitster@pobox.com> 1557386967 +0900

difftool --no-index: error out on --dir-diff (and don't crash)

In `--no-index` mode, we now no longer require a worktree nor a
repository. But some code paths in `difftool` expect those to be
present.

The most notable such code path is the `--dir-diff` one: we use the
existing checkout machinery to copy the files, and that machinery looks
up replacement refs, looks at alternate ODBs, wants to use the worktree
path, etc.

Rather than running into segmentation faults, let's die with an
informative error message.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>