Merge branch 'js/apply-recount-allow-noop'

When editing a patch in a "git add -i" session, a hunk could be
made to no-op.  The "git apply" program used to reject a patch with
such a no-op hunk to catch user mistakes, but it is now updated to
explicitly allow a no-op hunk in an edited patch.

* js/apply-recount-allow-noop:
  apply --recount: allow "no-op hunks"

Author: gitster

apply.c

@@ -1748,7 +1748,7 @@ static int parse_fragment(struct apply_state *state,
 	}
 	if (oldlines || newlines)
 		return -1;
-	if (!deleted && !added)
+	if (!patch->recount && !deleted && !added)
 		return -1;
 
 	fragment->leading = leading;

t/t4136-apply-check.sh

@@ -29,6 +29,18 @@ test_expect_success 'apply exits non-zero with no-op patch' '
 	test_must_fail git apply --check input
 '
 
+test_expect_success '`apply --recount` allows no-op patch' '
+	echo 1 >1 &&
+	git apply --recount --check <<-\EOF
+	diff --get a/1 b/1
+	index 6696ea4..606eddd 100644
+	--- a/1
+	+++ b/1
+	@@ -1,1 +1,1 @@
+	 1
+	EOF
+'
+
 test_expect_success 'invalid combination: create and copy' '
 	test_must_fail git apply --check - <<-\EOF
 	diff --git a/1 b/2