git stash: add --index-only, or --keep-index should not stash index?

[Piotr Krukowiecki <piotr.krukowiecki@gmail.com>]

Hi,

I wanted to do something like "Testing partial commits" described in
git-stash documentation (see end of mail for reference). I think this
is a common scenario: you start working on some feature, then discover
a bug, start fixing it, but realize it needs more work. So now you have
two features that needs more work (both are not ready for committing). 

The documentation says to use --keep-index in this case.

The problem is that --keep-index leaves changes in index intact, but at
the same time it saves them in stash. So if I edit those changes I'm likely
to get conflicts when applying the stash.

For example:

$ git init && echo a > a && git add . && git commit -m a
$ echo x > a && git add a && git stash save --keep-index
$ echo y > a && git add a && git commit -m y
$ git stash pop
Auto-merging a
CONFLICT (content): Merge conflict in a

Maybe --keep-index should not stash staged changes? This would fix this
problem. And I can't  think of a situation when would want to stash changes
and at the same time keep them.

If --keep-index works correctly maybe a new option, for example --index-only
(or --cached-only?) could be introduced?


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Testing partial commits::

You can use `git stash save --keep-index` when you want to make two or
more commits out of the changes in the work tree, and you want to test
each change before committing:
+
----------------------------------------------------------------
# ... hack hack hack ...
$ git add --patch foo            # add just first part to the index
$ git stash save --keep-index    # save all other changes to the stash
$ edit/build/test first part
$ git commit -m 'First part'     # commit fully tested change
$ git stash pop                  # prepare to work on all other changes
# ... repeat above five steps until one commit remains ...
$ edit/build/test remaining parts
$ git commit foo -m 'Remaining parts'
----------------------------------------------------------------


-- 
Piotr Krukowiecki