The "recursive" backend relies on unpack_trees() to check if unstaged
changes would be overwritten by a merge, but unpack_trees() does not
understand renames -- and once it returns, it has already written many
updates to the working tree and index. As such, "recursive" had to do a
special 4-way merge where it would need to also treat the working copy
as an extra source of differences that we had to carefully avoid
overwriting and resulting in moving files to new locations to avoid
conflicts.
The "ort" backend, by contrast, does the complete merge inmemory, and
only updates the index and working copy as a post-processing step. If
there are dirty files in the way, it can simply abort the merge.
Update t6423 and t6436 to reflect the better merge abilities and
expectations we have for ort, while still leaving the
best-case-as-good-as-recursive-can-do expectations there for the
recursive backend so we retain its stability until we are ready to
deprecate and remove it.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The tests for the merge machinery are spread over several places.
Collect them into t64xx for simplicity. Some notes:
t60[234]*.sh:
Merge tests started in t602*, overgrew bisect and remote tracking
tests in t6030, t6040, and t6041, and nearly overtook replace tests
in t6050. This made picking out relevant tests that I wanted to run
in a tighter loop slightly more annoying for years.
t303*.sh:
These started out as tests for the 'merge-recursive' toplevel command,
but did not restrict to that and had lots of overlap with the
underlying merge machinery.
t7405, t7613:
submodule-specific merge logic started out in submodule.c but was
moved to merge-recursive.c in commit 18cfc08866 ("submodule.c: move
submodule merging to merge-recursive.c", 2018-05-15). Since these
tests are about the logic found in the merge machinery, moving these
tests to be with the merge tests makes sense.
t7607, t7609:
Having tests spread all over the place makes it more likely that
additional tests related to a certain piece of logic grow in all those
other places. Much like t303*.sh, these two tests were about the
underlying merge machinery rather than outer levels.
Tests that were NOT moved:
t76[01]*.sh:
Other than the four tests mentioned above, the remaining tests in
t76[01]*.sh are related to non-recursive merge strategies, parameter
parsing, and other stuff associated with the highlevel builtin/merge.c
rather than the recursive merge machinery.
t3[45]*.sh:
The rebase testcases in t34*.sh also test the merge logic pretty
heavily; sometimes changes I make only trigger failures in the rebase
tests. The rebase tests are already nicely coupled together, though,
and I didn't want to mess that up. Similar comments apply for the
cherry-pick tests in t35*.sh.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Elijah Newren