revision.c: explain what tree_difference does

diff --git a/git-reset.sh b/git-reset.sh
index 5c0224090a252bed3258bbbb127e84e61a874197..fee6d98d9cba708828c36a2d2a29dbec8662c36b 100755 (executable)
--- a/git-reset.sh
+++ b/git-reset.sh
@@ -1,31 +1,60 @@
 #!/bin/sh
-
-USAGE='[--mixed | --soft | --hard]  [<commit-ish>]'
+#
+# Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
+#
+USAGE='[--mixed | --soft | --hard]  [<commit-ish>] [ [--] <paths>...]'
+SUBDIRECTORY_OK=Yes
 . git-sh-setup
+set_reflog_action "reset $*"
+require_work_tree
 
-tmp=${GIT_DIR}/reset.$$
-trap 'rm -f $tmp-*' 0 1 2 3 15
+update= reset_type=--mixed
+unset rev
 
-update=
-reset_type=--mixed
-case "$1" in
---mixed | --soft | --hard)
-       reset_type="$1"
+while case $# in 0) break ;; esac
+do
+       case "$1" in
+       --mixed | --soft | --hard)
+               reset_type="$1"
+               ;;
+       --)
+               break
+               ;;
+       -*)
+               usage
+               ;;
+       *)
+               rev=$(git-rev-parse --verify "$1") || exit
+               shift
+               break
+               ;;
+       esac
        shift
-       ;;
--*)
-        usage ;;
-esac
+done
 
-case $# in
-0) rev=HEAD ;;
-1) rev=$(git-rev-parse --verify "$1") || exit ;;
-*) usage ;;
-esac
+: ${rev=HEAD}
 rev=$(git-rev-parse --verify $rev^0) || exit
 
-# We need to remember the set of paths that _could_ be left
-# behind before a hard reset, so that we can remove them.
+# Skip -- in "git reset HEAD -- foo" and "git reset -- foo".
+case "$1" in --) shift ;; esac
+
+# git reset --mixed tree [--] paths... can be used to
+# load chosen paths from the tree into the index without
+# affecting the working tree nor HEAD.
+if test $# != 0
+then
+       test "$reset_type" = "--mixed" ||
+               die "Cannot do partial $reset_type reset."
+
+       git-diff-index --cached $rev -- "$@" |
+       sed -e 's/^:\([0-7][0-7]*\) [0-7][0-7]* \([0-9a-f][0-9a-f]*\) [0-9a-f][0-9a-f]* [A-Z]   \(.*\)$/\1 \2   \3/' |
+       git update-index --add --remove --index-info || exit
+       git update-index --refresh
+       exit
+fi
+
+cd_to_toplevel
+
 if test "$reset_type" = "--hard"
 then
        update=-u
@@ -52,11 +81,17 @@ then
 else
        rm -f "$GIT_DIR/ORIG_HEAD"
 fi
-git-update-ref -m "reset $reset_type $@" HEAD "$rev"
+git-update-ref -m "$GIT_REFLOG_ACTION" HEAD "$rev"
+update_ref_status=$?
 
 case "$reset_type" in
 --hard )
-       ;; # Nothing else to do
+       test $update_ref_status = 0 && {
+               printf "HEAD is now at "
+               GIT_PAGER= git log --max-count=1 --pretty=oneline \
+                       --abbrev-commit HEAD
+       }
+       ;;
 --soft )
        ;; # Nothing else to do
 --mixed )
@@ -65,4 +100,7 @@ case "$reset_type" in
        ;;
 esac
 
-rm -f "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/rr-cache/MERGE_RR" "$GIT_DIR/SQUASH_MSG"
+rm -f "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/rr-cache/MERGE_RR" \
+       "$GIT_DIR/SQUASH_MSG" "$GIT_DIR/MERGE_MSG"
+
+exit $update_ref_status