merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/t/t3305-notes-fanout.sh

@@ -0,0 +1,92 @@
+#!/bin/sh
+
+test_description='Test that adding/removing many notes triggers automatic fanout restructuring'
+
+. ./test-lib.sh
+
+test_expect_success 'creating many notes with git-notes' '
+	num_notes=300 &&
+	i=0 &&
+	while test $i -lt $num_notes
+	do
+		i=$(($i + 1)) &&
+		test_tick &&
+		echo "file for commit #$i" > file &&
+		git add file &&
+		git commit -q -m "commit #$i" &&
+		git notes add -m "note #$i" || return 1
+	done
+'
+
+test_expect_success 'many notes created correctly with git-notes' '
+	git log | grep "^    " > output &&
+	i=300 &&
+	while test $i -gt 0
+	do
+		echo "    commit #$i" &&
+		echo "    note #$i" &&
+		i=$(($i - 1));
+	done > expect &&
+	test_cmp expect output
+'
+
+test_expect_success 'many notes created with git-notes triggers fanout' '
+	# Expect entire notes tree to have a fanout == 1
+	git ls-tree -r --name-only refs/notes/commits |
+	while read path
+	do
+		case "$path" in
+		??/??????????????????????????????????????)
+			: true
+			;;
+		*)
+			echo "Invalid path \"$path\"" &&
+			return 1
+			;;
+		esac
+	done
+'
+
+test_expect_success 'deleting most notes with git-notes' '
+	num_notes=250 &&
+	i=0 &&
+	git rev-list HEAD |
+	while test $i -lt $num_notes && read sha1
+	do
+		i=$(($i + 1)) &&
+		test_tick &&
+		git notes remove "$sha1" ||
+		exit 1
+	done
+'
+
+test_expect_success 'most notes deleted correctly with git-notes' '
+	git log HEAD~250 | grep "^    " > output &&
+	i=50 &&
+	while test $i -gt 0
+	do
+		echo "    commit #$i" &&
+		echo "    note #$i" &&
+		i=$(($i - 1));
+	done > expect &&
+	test_cmp expect output
+'
+
+test_expect_success 'deleting most notes triggers fanout consolidation' '
+	# Expect entire notes tree to have a fanout == 0
+	git ls-tree -r --name-only refs/notes/commits |
+	while read path
+	do
+		case "$path" in
+		????????????????????????????????????????)
+			: true
+			;;
+		*)
+			echo "Invalid path \"$path\"" &&
+			return 1
+			;;
+		esac
+	done
+'
+
+test_done