On Mon, Mar 8, 2021 at 7:07 AM Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> wrote: > > Add a test to stress the "a->mode == b->mode" comparison in > merge-tree.c's same_entry(). I can't remember now; did you remove the preliminary canon_mode()? If so, does this check actually need to be generalized? For example, if someone has a git repository where a mode on a file in one part of history is 100666, and on the other is 100644, then the equality comparison no longer is satisfied because the modes haven't been canonicalized. Yet it's clear how the merge-tree should resolve it -- both are regular, non-executable files, so the merged mode should be 100644. > That code was initially added by Linus in 33deb63a36f (Add > "merge-tree" helper program. Maybe it's retarded, maybe it's helpful., > 2005-04-14), and then again in its current form in > 492e0759bfe (Handling large files with GIT, 2006-02-14). > > However, nothing was testing that we handled this case > correctly. Simply removing the mode comparison left all tests passing, > but as seen here it's important that we don't think a path with the > same content but different modes is the same_entry(). > > The rest of this series will touch code that's relevant to this, but > won't change its behavior. This test is just something I came up with > in testing whether the mode test in same_entry() was needed at all. > > Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> > --- > t/t4300-merge-tree.sh | 44 +++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 44 insertions(+) > > diff --git a/t/t4300-merge-tree.sh b/t/t4300-merge-tree.sh > index e59601e5fe9..f783d784d02 100755 > --- a/t/t4300-merge-tree.sh > +++ b/t/t4300-merge-tree.sh > @@ -40,6 +40,25 @@ test_expect_success 'file add A, B (same)' ' > test_must_be_empty actual > ' > > +test_expect_success 'file add A, B (different mode)' ' > + git reset --hard initial && > + test_commit "add-a-b-same-diff-mode-A" "ONE" "AAA" && > + git reset --hard initial && > + echo AAA >ONE && > + test_chmod +x ONE && > + test_tick && > + git commit -m"add-a-b-same-diff-mode-B" && > + git tag "add-a-b-same-diff-mode-B" HEAD && > + git merge-tree initial add-a-b-same-diff-mode-A add-a-b-same-diff-mode-B >actual && > + cat >expected <<EXPECTED && > +added in both > + our 100644 $(git rev-parse add-a-b-same-diff-mode-A:ONE) ONE > + their 100755 $(git rev-parse add-a-b-same-diff-mode-B:ONE) ONE > +EXPECTED > + > + test_cmp expected actual > +' > + > test_expect_success 'file add A, B (different)' ' > git reset --hard initial && > test_commit "add-a-b-diff-A" "ONE" "AAA" && > @@ -61,6 +80,31 @@ EXPECTED > test_cmp expected actual > ' > > +test_expect_success 'file add A, B (different and different mode)' ' > + git reset --hard initial && > + test_commit "add-a-b-diff-diff-mode-A" "ONE" "AAA" && > + git reset --hard initial && > + echo BBB >ONE && > + test_chmod +x ONE && > + test_tick && > + git commit -m"add-a-b-diff-diff-mode-B" && > + git tag "add-a-b-diff-diff-mode-B" && > + git merge-tree initial add-a-b-diff-diff-mode-A add-a-b-diff-diff-mode-B >actual && > + cat >expected <<EXPECTED && > +added in both > + our 100644 $(git rev-parse add-a-b-diff-diff-mode-A:ONE) ONE > + their 100755 $(git rev-parse add-a-b-diff-diff-mode-B:ONE) ONE > +@@ -1 +1,5 @@ > ++<<<<<<< .our > + AAA > ++======= > ++BBB > ++>>>>>>> .their > +EXPECTED > + > + test_cmp expected actual > +' > + > test_expect_success 'file change A, !B' ' > git reset --hard initial && > test_commit "change-a-not-b" "initial-file" "BBB" && > -- > 2.31.0.rc0.126.g04f22c5b82
