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

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

third_party/git/t/perf/p0001-rev-list.sh

@@ -0,0 +1,48 @@
+#!/bin/sh
+
+test_description="Tests history walking performance"
+
+. ./perf-lib.sh
+
+test_perf_default_repo
+
+test_perf 'rev-list --all' '
+	git rev-list --all >/dev/null
+'
+
+test_perf 'rev-list --all --objects' '
+	git rev-list --all --objects >/dev/null
+'
+
+test_perf 'rev-list --parents' '
+	git rev-list --parents HEAD >/dev/null
+'
+
+test_expect_success 'create dummy file' '
+	echo unlikely-to-already-be-there >dummy &&
+	git add dummy &&
+	git commit -m dummy
+'
+
+test_perf 'rev-list -- dummy' '
+	git rev-list HEAD -- dummy
+'
+
+test_perf 'rev-list --parents -- dummy' '
+	git rev-list --parents HEAD -- dummy
+'
+
+test_expect_success 'create new unreferenced commit' '
+	commit=$(git commit-tree HEAD^{tree} -p HEAD) &&
+	test_export commit
+'
+
+test_perf 'rev-list $commit --not --all' '
+	git rev-list $commit --not --all >/dev/null
+'
+
+test_perf 'rev-list --objects $commit --not --all' '
+	git rev-list --objects $commit --not --all >/dev/null
+'
+
+test_done