Re: [PATCH 2/3] git-bundle: die if a given ref is not included in bundle

Junio C Hamano wrote:

If I were doing a nightly script, I would probably be doing
something like this:

	#!/bin/sh
	yesterday=$(git bundle list-heads yesterday.bdl | sed -e 's/ .*//')
	git bundle create today.bdl --all --not $yesterday
	# mail it out

Thinking about this further, the above has a problem (or should, but see 
below). Consider a case where master is not updated since yesterday. 
Effectively, the above becomes

git bundle create today.bdl  master <other-refs> --not master <other-refs>

As ref master is excluded, the bundle creation should die because master 
cannot be included. Experimenting with next (299fcfbdcb5afd85) however, 
I get:

git>git bundle create t.bdl master --not master
Generating pack...
Done counting 0 objects.
Writing 0 objects.
Total 0 (delta 0), reused 0 (delta 0)
git>git ls-remote t.bdl
git>

e.g, an empty bundle is created without any error or warning. This is 
the one case I believe an error should result: there is no use to 
sending (or even creating) an empty bundle.

As a date limited bundle containing all updated refs is my basic use, I 
really want this case to not be hard, and it definitely should not 
require externally maintained history or scripting to create. Absent the 
"die if any ref wasn't updated in the given date range" logic, and 
adding always die if the resulting bundle is empty, git bundle in next 
accomplishes what I want.

Mark