Commit Graph

13 Commits

Author SHA1 Message Date
Elijah Newren
bfbd201e39 tests: remove GIT_TEST_MERGE_ALGORITHM and test_expect_merge_algorithm
Both of these existed to allow us to reuse all the merge-related tests
in the testsuite while easily flipping between the 'recursive' and the
'ort' backends.  Now that we have removed merge-recursive and remapped
'recursive' to mean 'ort', we don't need this scaffolding anymore.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-04-08 13:59:13 -07:00
Elijah Newren
77c029493a builtin/merge-recursive: switch to using merge_ort_generic()
Switch from merge-recursive to merge-ort.  Adjust the following
testcases due to the switch:

* t6430: most of the test differences here were due to improved D/F
  conflict handling explained in more detail in ef52778708 (merge
  tests: expect improved directory/file conflict handling in ort,
  2020-10-26).  These changes weren't made to this test back in that
  commit simply because I had been looking at `git merge` rather than
  `git merge-recursive`.  The final test in this testsuite, though, was
  expunged because it was looking for specific output, and the calls to
  output_commit_title() were discarded from merge_ort_internal() in its
  adaptation from merge_recursive_internal(); see 8119214f4e
  (merge-ort: implement merge_incore_recursive(), 2020-12-16).

* t6434: This test is built entirely around rename/delete conflicts,
  which had a suboptimal handling under merge-recursive.  As explained
  in more detail in commits 1f3c9ba707 ("t6425: be more flexible with
  rename/delete conflict messages", 2020-08-10) and 727c75b23f ("t6404,
  t6423: expect improved rename/delete handling in ort backend",
  2020-10-26), rename/delete conflicts should each have two entries in
  the index rather than just one.  Adjust the expectations for all the
  tests in this testcase to see the two entries per rename/delete
  conflict.

* t6424: merge-recursive had a special check-if-toplevel-trees-match
  check that it ran at the beginning on both the merge-base and the
  other side being merged in.  In such a case, it exited early and
  printed an "Already up to date." message.  merge-ort got rid of
  this, and instead checks the merge base tree matching the other
  side throughout the tree instead of just at the toplevel, allowing
  it to avoid recursing into various subtrees.  As part of that, it
  got rid of the specialty toplevel message.  That message hasn't
  been missed for years from `git merge`, so I don't think it is
  necessary to keep it just for `git merge-recursive`, especially
  since the latter is rarely used.  (git itself only references it
  in the testsuite, whereas it used to power one of the three
  rebase backends that existed once upon a time.)

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-04-08 13:59:11 -07:00
Patrick Steinhardt
fc1ddf42af t: remove TEST_PASSES_SANITIZE_LEAK annotations
Now that the default value for TEST_PASSES_SANITIZE_LEAK is `true` there
is no longer a need to have that variable declared in all of our tests.
Drop it.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-21 08:23:48 +09:00
Patrick Steinhardt
ff67083ccd builtin/merge: release output buffer after performing merge
The `obuf` member of `struct merge_options` is used to buffer output in
some cases. In order to not discard its allocated memory we only release
its contents in `merge_finalize()` when we're not currently recursing
into a subtree.

This results in some situations where we seemingly do not release the
buffer reliably. We thus have calls to `strbuf_release()` for this
buffer scattered across the codebase. But we're missing one callsite in
git-merge(1), which causes a memory leak.

We should ideally refactor this interface so that callers don't have to
know about any such internals. But for now, paper over the issue by
adding one more `strbuf_release()` call.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-04 22:37:57 -08:00
Junio C Hamano
6789275d37 tests: teach callers of test_i18ngrep to use test_grep
They are equivalents and the former still exists, so as long as the
only change this commit makes are to rewrite test_i18ngrep to
test_grep, there won't be any new bug, even if there still are
callers of test_i18ngrep remaining in the tree, or when merged to
other topics that add new uses of test_i18ngrep.

This patch was produced more or less with

    git grep -l -e 'test_i18ngrep ' 't/t[0-9][0-9][0-9][0-9]-*.sh' |
    xargs perl -p -i -e 's/test_i18ngrep /test_grep /'

and a good way to sanity check the result yourself is to run the
above in a checkout of c4603c1c (test framework: further deprecate
test_i18ngrep, 2023-10-31) and compare the resulting working tree
contents with the result of applying this patch to the same commit.
You'll see that test_i18ngrep in a few t/lib-*.sh files corrected,
in addition to the manual reproduction.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-02 17:13:44 +09:00
Elijah Newren
aa77ce88ed merge: make restore_state() restore staged state too
There are multiple issues at play here:

  1) If `git merge` is invoked with staged changes, it should abort
     without doing any merging, and the user's working tree and index
     should be the same as before merge was invoked.
  2) Merge strategies are responsible for enforcing the index == HEAD
     requirement. (See 9822175d2b ("Ensure index matches head before
     invoking merge machinery, round N", 2019-08-17) for some history
     around this.)
  3) Merge strategies can bail saying they are not an appropriate
     handler for the merge in question (possibly allowing other
     strategies to be used instead).
  4) Merge strategies can make changes to the index and working tree,
     and have no expectation to clean up after themselves, *even* if
     they bail out and say they are not an appropriate handler for
     the merge in question.  (The `octopus` merge strategy does this,
     for example.)
  5) Because of (3) and (4), builtin/merge.c stashes state before
     trying merge strategies and restores it afterward.

Unfortunately, if users had staged changes before calling `git merge`,
builtin/merge.c could do the following:

   * stash the changes, in order to clean up after the strategies
   * try all the merge strategies in turn, each of which report they
     cannot function due to the index not matching HEAD
   * restore the changes via "git stash apply"

But that last step would have the net effect of unstaging the user's
changes.  Fix this by adding the "--index" option to "git stash apply".
While at it, also squelch the stash apply output; we already report
"Rewinding the tree to pristine..." and don't need a detailed `git
status` report afterwards.  Also while at it, switch to using strvec
so folks don't have to count the arguments to ensure we avoided an
off-by-one error, and so it's easier to add additional arguments to
the command.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:45:23 -07:00
Elijah Newren
1369f1475b merge: fix save_state() to work when there are stat-dirty files
When there are stat-dirty files, but no files are modified,
`git stash create` exits with unsuccessful status.  This causes merge
to fail.  Copy some code from sequencer.c's create_autostash to refresh
the index first to avoid this problem.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:45:23 -07:00
Elijah Newren
8f240b8bbb merge: do not abort early if one strategy fails to handle the merge
builtin/merge is setup to allow multiple strategies to be specified,
and it will find the "best" result and use it.  This is defeated if
some of the merge strategies abort early when they cannot handle the
merge.  Fix the logic that calls recursive and ort to not do such an
early abort, but instead return "2" or "unhandled" so that the next
strategy can try to handle the merge.

Coming up with a testcase for this is somewhat difficult, since
recursive and ort both handle nearly any two-headed merge (there is
a separate code path that checks for non-two-headed merges and
already returns "2" for them).  So use a somewhat synthetic testcase
of having the index not match HEAD before the merge starts, since all
merge strategies will abort for that.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:45:23 -07:00
Elijah Newren
e4cdfe84a0 merge: abort if index does not match HEAD for trivial merges
As noted in the last commit and the links therein (especially commit
9822175d2b ("Ensure index matches head before invoking merge machinery,
round N", 2019-08-17), we have had a very long history of problems with
failing to enforce the requirement that index matches HEAD when starting
a merge.

The "trivial merge" logic in builtin/merge.c is yet another such case
we previously missed.  Add a check for it to ensure it aborts if the
index does not match HEAD, and add a testcase where this fix is needed.

Note that the fix here would also incidentally be an alternative fix
for the testcase added in the last patch, but the fix in the last patch
is still needed when multiple merge strategies are in use, so tweak the
testcase from the previous commit so that it continues to exercise the
codepath added in the last commit.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:45:23 -07:00
Elijah Newren
24ba8b70c9 merge-resolve: abort if index does not match HEAD
As noted in commit 9822175d2b ("Ensure index matches head before
invoking merge machinery, round N", 2019-08-17), we have had a very
long history of problems with failing to enforce the requirement that
index matches HEAD when starting a merge.  One of the commits
referenced in the long tale of issues arising from lax enforcement of
this requirement was commit 55f39cf755 ("merge: fix misleading
pre-merge check documentation", 2018-06-30), which tried to document
the requirement and noted there were some exceptions.  As mentioned in
that commit message, the `resolve` strategy was the one strategy that
did not have an explicit index matching HEAD check, and the reason it
didn't was that I wasn't able to discover any cases where the
implementation would fail to catch the problem and abort, and didn't
want to introduce unnecessary performance overhead of adding another
check.

Well, today I discovered a testcase where the implementation does not
catch the problem and so an explicit check is needed.  Add a testcase
that previously would have failed, and update git-merge-resolve.sh to
have an explicit check.  Note that the code is copied from 3ec62ad9ff
("merge-octopus: abort if index does not match HEAD", 2016-04-09), so
that we reuse the same message and avoid making translators need to
translate some new message.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-22 21:45:22 -07:00
Junio C Hamano
4b317450ce t6424: make sure a failed merge preserves local changes
We do make sure that an attempt to merge with various forms of local
changes will "fail", but the point of stopping the merge is so that
we refrain from discarding uncommitted local changes that could be
precious.  Add a few more checks for each case to make sure the
local changes are left intact.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-05-19 12:03:00 -07:00
Elijah Newren
f222bd34ff tests: remove leftover untracked files
Remove untracked files that are unwanted after they are done being used.

While the set of cases in this patch is certainly far from
comprehensive, it was motivated by some work to see what the fallout
would be if we were to make the removal of untracked files as a side
effect of other commands into an error.  Some cases were a bit more
involved than the testcase changes included in this patch, but the ones
included here represent the simple cases.  While this patch is not that
important since we are not changing the behavior of those other commands
into an error in the near term, I thought these changes were useful
anyway as an explicit documentation of the intent that these untracked
files are no longer useful.

Acked-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Acked-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-12 16:42:40 -07:00
Elijah Newren
919df31955 Collect merge-related tests to t64xx
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>
2020-08-10 15:59:00 -07:00