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

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

third_party/git/t/t4126-apply-empty.sh

@@ -0,0 +1,57 @@
+#!/bin/sh
+
+test_description='apply empty'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+	>empty &&
+	git add empty &&
+	test_tick &&
+	git commit -m initial &&
+	for i in a b c d e
+	do
+		echo $i
+	done >empty &&
+	cat empty >expect &&
+	git diff |
+	sed -e "/^diff --git/d" \
+	    -e "/^index /d" \
+	    -e "s|a/empty|empty.orig|" \
+	    -e "s|b/empty|empty|" >patch0 &&
+	sed -e "s|empty|missing|" patch0 >patch1 &&
+	>empty &&
+	git update-index --refresh
+'
+
+test_expect_success 'apply empty' '
+	git reset --hard &&
+	rm -f missing &&
+	git apply patch0 &&
+	test_cmp expect empty
+'
+
+test_expect_success 'apply --index empty' '
+	git reset --hard &&
+	rm -f missing &&
+	git apply --index patch0 &&
+	test_cmp expect empty &&
+	git diff --exit-code
+'
+
+test_expect_success 'apply create' '
+	git reset --hard &&
+	rm -f missing &&
+	git apply patch1 &&
+	test_cmp expect missing
+'
+
+test_expect_success 'apply --index create' '
+	git reset --hard &&
+	rm -f missing &&
+	git apply --index patch1 &&
+	test_cmp expect missing &&
+	git diff --exit-code
+'
+
+test_done