Merge branch 'pw/diff-no-index-from-named-pipes'

"git diff --no-index -R <(one) <(two)" did not work correctly,
which has been corrected.

* pw/diff-no-index-from-named-pipes:
  diff --no-index: fix -R with stdin

diff-no-index.c

@@ -232,6 +232,7 @@ static int queue_diff(struct diff_options *o,
 		if (o->flags.reverse_diff) {
 			SWAP(mode1, mode2);
 			SWAP(name1, name2);
+			SWAP(special1, special2);
 		}
 
 		d1 = noindex_filespec(name1, mode1, special1);

t/t4053-diff-no-index.sh

@@ -224,6 +224,25 @@ test_expect_success "diff --no-index treats '-' as stdin" '
 	test_must_be_empty actual
 '
 
+test_expect_success "diff --no-index -R treats '-' as stdin" '
+	cat >expect <<-EOF &&
+	diff --git b/a/1 a/-
+	index $(git hash-object --stdin <a/1)..$ZERO_OID 100644
+	--- b/a/1
+	+++ a/-
+	@@ -1 +1 @@
+	-1
+	+x
+	EOF
+
+	test_write_lines x | test_expect_code 1 \
+		git -c core.abbrev=no diff --no-index -R -- - a/1 >actual &&
+	test_cmp expect actual &&
+
+	test_write_lines 1 | git diff --no-index -R -- a/1 - >actual &&
+	test_must_be_empty actual
+'
+
 test_expect_success 'diff --no-index refuses to diff stdin and a directory' '
 	test_must_fail git diff --no-index -- - a </dev/null 2>err &&
 	grep "fatal: cannot compare stdin to a directory" err