apply --recount: allow "no-op hunks"

When editing patches e.g. in `git add -e`, it is quite common that a hunk ends up having no -/+ lines, i.e. it is now supposed to do nothing. This use case was broken by ad6e8ed37bc1 (apply: reject a hunk that does not do anything, 2015-06-01) with the good intention of catching a very real, different issue in hand-edited patches. So let's use the `--recount` option as the tell-tale whether the user would actually be okay with no-op hunks. Add a test case to make sure that this use case does not regress again. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Reviewed-by: Josh Steadmon <steadmon@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Johannes Schindelin committed Nov 12, 2018 at 12:54 UTC 22cb3835b90f80b2de2bc8f5ff3a9e8eed5ff40a
2 files changed +13 -1
apply.c
+1 -1
@@ -1747,7 +1747,7 @@ static int parse_fragment(struct apply_state *state,
1747 }
1748 if (oldlines || newlines)
1749 return -1;
1750 - if (!deleted && !added)
1750 + if (!patch->recount && !deleted && !added)
1751 return -1;
1752
1753 fragment->leading = leading;
t/t4136-apply-check.sh
+12
@@ -29,6 +29,18 @@ test_expect_success 'apply exits non-zero with no-op patch' '
29 test_must_fail git apply --check input
30 '
31
32 +test_expect_success '`apply --recount` allows no-op patch' '
33 + echo 1 >1 &&
34 + git apply --recount --check <<-\EOF
35 + diff --get a/1 b/1
36 + index 6696ea4..606eddd 100644
37 + --- a/1
38 + +++ b/1
39 + @@ -1,1 +1,1 @@
40 + 1
41 + EOF
42 +'
43 +
44 test_expect_success 'invalid combination: create and copy' '
45 test_must_fail git apply --check - <<-\EOF
46 diff --git a/1 b/2