Re: [RFC PATCH v2 3/4] unpack_trees(): add support for sparse checkout

Hi,

On Mon, 10 Aug 2009, Nguyễn Thái Ngọc Duy wrote:

This patch teaches unpack_trees() to checkout/remove entries on working 
directories appropriately when sparse checkout area is changed. Hook 
"sparse" is needed to help determine which entry will be checked out, 
which will not be.

When the hook is run, it is prepared with a pseudo index. The hook then 
can use "git update-index --[no-]assume-unchanged" to manipulate the 
index. It should not do anything else on the index. Assume unchanged 
information from the index will be used to shape working directory.

If I understand correctly, the purpose of the hook is to allow the user to 
mark something as unwanted preemptively, right?

If that is the sole reason for the hook, would it not be better to add 
support for a file .git/info/sparse which has the same syntax as 
.git/info/exclude, and which is used to determine if an 
added/modified/deleted file is supposed to be in the "sparse" area or not?

Something like

	*
	!/Documentation/

comes to mind.

Thanks,
Dscho