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

3 files changed, 61 insertions, 8 deletions

diff --git a/t/t4208-log-magic-pathspec.sh b/t/t4208-log-magic-pathspec.sh
index 5e10136e9a..7f0c1dcc0f 100755
--- a/t/t4208-log-magic-pathspec.sh
+++ b/t/t4208-log-magic-pathspec.sh
@@ -31,13 +31,8 @@ test_expect_success '"git log :/a -- " should not be ambiguous' '
 test_expect_success '"git log :/detached -- " should find a commit only in HEAD' '
 	test_when_finished "git checkout main" &&
 	git checkout --detach &&
-	# Must manually call `test_tick` instead of using `test_commit`,
-	# because the latter additionally creates a tag, which would make
-	# the commit reachable not only via HEAD.
-	test_tick &&
-	git commit --allow-empty -m detached &&
-	test_tick &&
-	git commit --allow-empty -m something-else &&
+	test_commit --no-tag detached &&
+	test_commit --no-tag something-else &&
 	git log :/detached --
 '
 
diff --git a/t/t6115-rev-list-du.sh b/t/t6115-rev-list-du.sh
new file mode 100755
index 0000000000..b4aef32b71
--- /dev/null
+++ b/t/t6115-rev-list-du.sh
@@ -0,0 +1,51 @@
+#!/bin/sh
+
+test_description='basic tests of rev-list --disk-usage'
+. ./test-lib.sh
+
+# we want a mix of reachable and unreachable, as well as
+# objects in the bitmapped pack and some outside of it
+test_expect_success 'set up repository' '
+	test_commit --no-tag one &&
+	test_commit --no-tag two &&
+	git repack -adb &&
+	git reset --hard HEAD^ &&
+	test_commit --no-tag three &&
+	test_commit --no-tag four &&
+	git reset --hard HEAD^
+'
+
+# We don't want to hardcode sizes, because they depend on the exact details of
+# packing, zlib, etc. We'll assume that the regular rev-list and cat-file
+# machinery works and compare the --disk-usage output to that.
+disk_usage_slow () {
+	git rev-list --no-object-names "$@" |
+	git cat-file --batch-check="%(objectsize:disk)" |
+	perl -lne '$total += $_; END { print $total}'
+}
+
+# check behavior with given rev-list options; note that
+# whitespace is not preserved in args
+check_du () {
+	args=$*
+
+	test_expect_success "generate expected size ($args)" "
+		disk_usage_slow $args >expect
+	"
+
+	test_expect_success "rev-list --disk-usage without bitmaps ($args)" "
+		git rev-list --disk-usage $args >actual &&
+		test_cmp expect actual
+	"
+
+	test_expect_success "rev-list --disk-usage with bitmaps ($args)" "
+		git rev-list --disk-usage --use-bitmap-index $args >actual &&
+		test_cmp expect actual
+	"
+}
+
+check_du HEAD
+check_du --objects HEAD
+check_du --objects HEAD^..HEAD
+
+test_done
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index c96a555ace..6348e8d733 100644
--- a/t/test-lib-functions.sh
+++ b/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>