Audit rev-parse users.

Make sure that we say --verify when we want to get a single SHA1
name.  Also when we say --verify, --revs-only is redundant.

Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/git-rebase-script b/git-rebase-script
index 7779813..026225a 100755
--- a/git-rebase-script
+++ b/git-rebase-script
@@ -28,7 +28,7 @@
 esac
 
 git-read-tree -m -u $ours $upstream &&
-echo "$upstream" >"$GIT_DIR/HEAD" || exit
+git-rev-parse --verify "$upstream^0" >"$GIT_DIR/HEAD" || exit
 
 tmp=.rebase-tmp$$
 fail=$tmp-fail
diff --git a/git-reset-script b/git-reset-script
index 49994df..7da8d86 100755
--- a/git-reset-script
+++ b/git-reset-script
@@ -1,7 +1,7 @@
 #!/bin/sh
 . git-sh-setup-script || die "Not a git archive"
-rev=$(git-rev-parse --revs-only --verify --default HEAD "$@") || exit
-rev=$(git-rev-parse --revs-only --verify $rev^0) || exit
+rev=$(git-rev-parse --verify --default HEAD "$@") || exit
+rev=$(git-rev-parse --verify $rev^0) || exit
 git-read-tree --reset "$rev" && {
 	if orig=$(git-rev-parse --verify HEAD 2>/dev/null)
 	then
diff --git a/git-tag-script b/git-tag-script
index d3074a8..39c3c53 100755
--- a/git-tag-script
+++ b/git-tag-script
@@ -47,7 +47,7 @@
 fi
 shift
 
-object=$(git-rev-parse --verify --revs-only --default HEAD "$@") || exit 1
+object=$(git-rev-parse --verify --default HEAD "$@") || exit 1
 type=$(git-cat-file -t $object) || exit 1
 tagger=$(git-var GIT_COMMITTER_IDENT) || exit 1