[PATCH] read-tree -m 3-way: loosen an index requirement that was too strict.
From: Junio C Hamano <hidden>
Date: 2016-06-15 22:41:59
Subsystem:
the rest · Maintainer:
Linus Torvalds
This patch teaches "read-tree -m O A B" that, when only "the other tree" changed a path, and if the work tree already has that change, we are not in a situation that would clobber the cache and the working tree, and lets the merge succeed; this is case #14ALT in t1000 test. It does not change the result of the merge, but prevents it from failing when it should not. Signed-off-by: Junio C Hamano <redacted> --- *** Rebased one from the last night. read-tree.c | 16 ++++++++++++++++ t/t1000-read-tree-m-3way.sh | 9 +++++++++ 2 files changed, 25 insertions(+), 0 deletions(-)
diff --git a/read-tree.c b/read-tree.c
--- a/read-tree.c
+++ b/read-tree.c@@ -140,6 +140,22 @@ static int threeway_merge(struct cache_e struct cache_entry *merge; int count; + /* The case #14ALT is special in that it allows "i" to match + * the "merged branch", aka "b" and even be dirty, as an + * alternative to the usual 'must match "a" and be up-to-date' + * rule. + */ + if (o && a && b && same(o, a) && !same(o, b)) { + if (i) { + if (same(i, b)) + ; /* case #14ALT exception */ + else if (same(i, a)) + verify_uptodate(i); + else + return -1; + } + } + else /* otherwise the original rule applies */ /* * If we have an entry in the index cache ("i"), then we want * to make sure that it matches any entries in stage 2 ("first
diff --git a/t/t1000-read-tree-m-3way.sh b/t/t1000-read-tree-m-3way.sh
--- a/t/t1000-read-tree-m-3way.sh
+++ b/t/t1000-read-tree-m-3way.sh@@ -455,6 +455,15 @@ test_expect_success \ git-read-tree -m $tree_O $tree_A $tree_B && check_result" +test_expect_success \ + '14ALT - in O && A && B && O==A && O!=B case, matching B is also OK' \ + "rm -f .git/index NM && + cp .orig-B/NM NM && + git-update-cache --add NM && + echo extra >>NM && + git-read-tree -m $tree_O $tree_A $tree_B && + check_result" + test_expect_failure \ '14 (fail) - must match and be up-to-date in O && A && B && O==A && O!=B case' \ "rm -f .git/index NM && ------------