From 6aba117d5cf7128e7bc942888263552fe927e13f Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Wed, 29 Aug 2018 00:06:13 -0700 Subject: [PATCH] am: avoid directory rename detection when calling recursive merge machinery Let's say you have the following three trees, where Base is from one commit behind either master or branch: Base : bar_v1, foo/{file1, file2, file3} branch: bar_v2, foo/{file1, file2}, goo/file3 master: bar_v3, foo/{file1, file2, file3} Using git-am (or am-based rebase) to apply the changes from branch onto master results in the following tree: Result: bar_merged, goo/{file1, file2, file3} This is not what users want; they did not rename foo/ -> goo/, they only renamed one file within that directory. The reason this happens is am constructs fake trees (via build_fake_ancestor()) of the following form: Base_bfa : bar_v1, foo/file3 branch_bfa: bar_v2, goo/file3 Combining these two trees with master's tree: master: bar_v3, foo/{file1, file2, file3}, You can see that merge_recursive_generic() would see branch_bfa as renaming foo/ -> goo/, and master as just adding both foo/file1 and foo/file2. As such, it ends up with goo/{file1, file2, file3} The core problem is that am does not have access to the original trees; it can only construct trees using the blobs involved in the patch. As such, it is not safe to perform directory rename detection within am -3. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- builtin/am.c | 1 + t/t3401-rebase-and-am-rename.sh | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/builtin/am.c b/builtin/am.c index 2fc2d1e82c..1494a9be84 100644 --- a/builtin/am.c +++ b/builtin/am.c @@ -1596,6 +1596,7 @@ static int fall_back_threeway(const struct am_state *state, const char *index_pa o.branch1 = "HEAD"; their_tree_name = xstrfmt("%.*s", linelen(state->msg), state->msg); o.branch2 = their_tree_name; + o.detect_directory_renames = 0; if (state->quiet) o.verbosity = 0; diff --git a/t/t3401-rebase-and-am-rename.sh b/t/t3401-rebase-and-am-rename.sh index 887bed5396..e0b5111993 100755 --- a/t/t3401-rebase-and-am-rename.sh +++ b/t/t3401-rebase-and-am-rename.sh @@ -152,7 +152,7 @@ test_expect_success 'rebase --interactive: NO directory rename' ' ) ' -test_expect_failure 'rebase (am): NO directory rename' ' +test_expect_success 'rebase (am): NO directory rename' ' test_when_finished "git -C no-dir-rename rebase --abort" && ( cd no-dir-rename && @@ -190,7 +190,7 @@ test_expect_success 'rebase --merge: NO directory rename' ' ) ' -test_expect_failure 'am: NO directory rename' ' +test_expect_success 'am: NO directory rename' ' test_when_finished "git -C no-dir-rename am --abort" && ( cd no-dir-rename &&