Merge branch 'jk/rev-list-disk-usage'

"git rev-list" command learned "--disk-usage" option.

* jk/rev-list-disk-usage:
  docs/rev-list: add some examples of --disk-usage
  docs/rev-list: add an examples section
  rev-list: add --disk-usage option for calculating disk usage
  t: add --no-tag option to test_commit

t/test-lib-functions.sh

@@ -190,6 +190,7 @@ test_commit () {
 	author= &&
 	signoff= &&
 	indir= &&
+	no_tag= &&
 	while test $# != 0
 	do
 		case "$1" in
@@ -216,6 +217,9 @@ test_commit () {
 			indir="$2"
 			shift
 			;;
+		--no-tag)
+			no_tag=yes
+			;;
 		*)
 			break
 			;;
@@ -238,7 +242,10 @@ test_commit () {
 	git ${indir:+ -C "$indir"} commit \
 	    ${author:+ --author "$author"} \
 	    $signoff -m "$1" &&
-	git ${indir:+ -C "$indir"} tag "${4:-$1}"
+	if test -z "$no_tag"
+	then
+		git ${indir:+ -C "$indir"} tag "${4:-$1}"
+	fi
 }
 
 # Call test_merge with the arguments "<message> <commit>", where <commit>