[PATCH] Add "clone" support to lntree

[Daniel Barkalow <barkalow@iabervon.org>]

I often want to take a base tree, which I keep tracking some remote head,
and make a local working tree that starts from it. This makes "git ln -c
<dest>" give you a tree that you can just start working in and then diff
against the head you'd started from and send off.

Signed-Off-By: Daniel Barkalow <barkalow@iabervon.org>

Index: gitlntree.sh
===================================================================
--- b068d3ec7c00cfe4a1f14a898f61c4807cd5bc8b/gitlntree.sh  (mode:100755 sha1:17c4966ea64aeced96ae4f1b00f3775c1904b0f1)
+++ 0877e1b9b70a4305959b7f65ace4044e4ae0afdb/gitlntree.sh  (mode:100755 sha1:84cbf0492996f1139b992147b4f53bc14342e3f2)
@@ -7,11 +7,14 @@
 # same objects database as the current one. It also shares the
 # branches and tags information.
 #
-# The new directory is completely pristine - there's not even
-# a directory cache there yet.
-#
 # Takes the new directory name.
 
+if [ "$1" = "-c" ]
+then
+    clone=yes
+    shift 1
+fi
+
 destdir=$1
 
 die () {
@@ -32,3 +35,12 @@
 ln -s $srcdir/.git/objects $dgitdir/objects
 ln -s $srcdir/.git/remotes $dgitdir/remotes
 ln -s $srcdir/.git/tags $dgitdir/tags
+
+if [ "$clone" != "" ]
+then
+    cp $srcdir/.git/HEAD $dgitdir/HEAD
+    cd $destdir
+    read-tree $(tree-id)
+    checkout-cache -a
+    update-cache --refresh
+fi