Make sure there is a work tree, i.e. the command cannot act
on bare repositories.
- This makes only sense when `RUN_SETUP` is also set.
+ This only makes sense when `RUN_SETUP` is also set.
. Add `builtin-foo.o` to `BUILTIN_OBJS` in `Makefile`.
. Add an entry for `git-foo` to `command-list.txt`.
+. Add an entry for `/git-foo` to `.gitignore`.
+
How a built-in is called
------------------------