Each of these were checked with
gcc -E -I. ${SOURCE_FILE} | grep ${HEADER_FILE}
to ensure that removing the direct inclusion of the header actually
resulted in that header no longer being included at all (i.e. that
no other header pulled it in transitively).
...except for a few cases where we verified that although the header
was brought in transitively, nothing from it was directly used in
that source file. These cases were:
* builtin/credential-cache.c
* builtin/pull.c
* builtin/send-pack.c
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix "git merge-tree" to stop segfaulting when the --attr-source
option is used.
* jc/merge-ort-attr-index-fix:
merge-ort: initialize repo in index state
initialize_attr_index() does not initialize the repo member of
attr_index. Starting in 44451a2e5e (attr: teach "--attr-source=<tree>"
global option to "git", 2023-05-06), this became a problem because
istate->repo gets passed down the call chain starting in
git_check_attr(). This gets passed all the way down to
replace_refs_enabled(), which segfaults when accessing r->gitdir.
Fix this by initializing the repository in the index state.
Signed-off-by: John Cai <johncai86@gmail.com>
Helped-by: Christian Couder <christian.couder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As noted in CodingGuidelines, error messages should not be capitalized.
Fix up a few of these that were copied verbatim from merge-recursive to
match our modern style.
We'll likewise fix up the matching ones from merge-recursive. We care a
bit less there, since the hope is that it will eventually go away. But
besides being the right thing to do in the meantime, it is necessary for
t6406 to pass both with and without GIT_TEST_MERGE_ALGORITHM set (one of
our CI jobs sets it to "recursive", which will use the merge-recursive.c
code). An alternative would be to use "grep -i" in the test to check
the message, but it's nice for the test suite to be be more exact (we'd
notice if the capitalization fix regressed).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The merge_options parameter has never been used since the function was
introduced in 64aceb6d73 (merge-ort: add code to check for whether
cached renames can be reused, 2021-05-20). In theory some merge options
might impact our decisions here, but that has never been the case so
far.
Let's drop it to appease -Wunused-parameter; it would be easy to add
back later if we need to (there is only one caller).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function takes three trees representing the merge base and both
sides of the merge, but never looks at any of them. This is due to
f78cf97617 (merge-ort: call diffcore_rename() directly, 2021-02-14).
Prior to that commit, we passed pairs of trees to diff_tree_oid(). But
after that commit, we collect a custom diff_queue for each pair in the
merge_options struct, and just run diffcore_rename() on the result. So
the function does not need to know about the original trees at all
anymore.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This function doesn't look at its merge_options parameter. It used to
pass it down to err(), but that function no longer exists (and didn't
look at "opt" anyway). We can drop it here.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The merge-ort code has an err() function, but it's really just error()
in disguise. It differs in two ways:
1. It takes a "struct merge_options" argument. But the function
completely ignores it! We can simply remove it.
2. It formats the error string into a strbuf, prepending "error: ",
and then feeds the result into error(). But this is wrong! The
error() function already adds the prefix, so we end up with:
error: error: Failed to execute internal merge
So let's just drop this function entirely and call error() directly, as
the functions are otherwise identical (note that they both always return
-1).
Presumably nobody noticed the bogus messages because they are quite hard
to trigger (they are mostly internal errors reading and writing
objects). However, one easy trigger is a custom merge driver which dies
by signal; we have a test already here, but we were not checking the
contents of stderr.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The vast majority of files including object-store.h did not need dir.h
nor khash.h. Split the header into two files, and let most just depend
upon object-store-ll.h, while letting the two callers that need it
depend on the full object-store.h.
After this patch:
$ git grep -h include..object-store | sort | uniq -c
2 #include "object-store.h"
129 #include "object-store-ll.h"
Diff best viewed with `--color-moved`.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A long term (but rather minor) pet-peeve of mine was the name
ll-merge.[ch]. I thought it made it harder to realize what stuff was
related to merging when I was working on the merge machinery and trying
to improve it.
Further, back in d1cbe1e6d8 ("hash-ll.h: split out of hash.h to remove
dependency on repository.h", 2023-04-22), we have split the portions of
hash.h that do not depend upon repository.h into a "hash-ll.h" (due to
the recommendation to use "ll" for "low-level" in its name[1], but which
I used as a suffix precisely because of my distaste for "ll-merge").
When we discussed adding additional "*-ll.h" files, a request was made
that we use "ll" consistently as either a prefix or a suffix. Since it
is already in use as both a prefix and a suffix, the only way to do so
is to rename some files.
Besides my distaste for the ll-merge.[ch] name, let me also note that
the files
ll-fsmonitor.h, ll-hash.h, ll-merge.h, ll-object-store.h, ll-read-cache.h
would have essentially nothing to do with each other and make no sense
to group. But giving them the common "ll-" prefix would group them. Using
"-ll" as a suffix thus seems just much more logical to me. Rename
ll-merge.[ch] to merge-ll.[ch] to achieve this consistency, and to
ensure we get a more logical grouping of files.
[1] https://lore.kernel.org/git/kl6lsfcu1g8w.fsf@chooglen-macbookpro.roam.corp.google.com/
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This also made it clear that several .c files that depended upon path.h
were missing a #include for it; add the missing includes while at it.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since this header showed up in some places besides just #include
statements, update/clean-up/remove those other places as well.
Note that compat/fsmonitor/fsm-path-utils-darwin.c previously got
away with violating the rule that all files must start with an include
of git-compat-util.h (or a short-list of alternate headers that happen
to include it first). This change exposed the violation and caused it
to stop building correctly; fix it by having it include
git-compat-util.h first, as per policy.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
For the functions defined in read-cache.c, move their declarations from
cache.h to a new header, read-cache-ll.h. Also move some related inline
functions from cache.h to read-cache.h. The purpose of the
read-cache-ll.h/read-cache.h split is that about 70% of the sites don't
need the inline functions and the extra headers they include.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Note in particular that this reverses the decision made in 118a2e8bde
("cache: move ensure_full_index() to cache.h", 2021-04-01).
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More header clean-up.
* en/header-split-cache-h-part-2: (22 commits)
reftable: ensure git-compat-util.h is the first (indirect) include
diff.h: reduce unnecessary includes
object-store.h: reduce unnecessary includes
commit.h: reduce unnecessary includes
fsmonitor: reduce includes of cache.h
cache.h: remove unnecessary headers
treewide: remove cache.h inclusion due to previous changes
cache,tree: move basic name compare functions from read-cache to tree
cache,tree: move cmp_cache_name_compare from tree.[ch] to read-cache.c
hash-ll.h: split out of hash.h to remove dependency on repository.h
tree-diff.c: move S_DIFFTREE_IFXMIN_NEQ define from cache.h
dir.h: move DTYPE defines from cache.h
versioncmp.h: move declarations for versioncmp.c functions from cache.h
ws.h: move declarations for ws.c functions from cache.h
match-trees.h: move declarations for match-trees.c functions from cache.h
pkt-line.h: move declarations for pkt-line.c functions from cache.h
base85.h: move declarations for base85.c functions from cache.h
copy.h: move declarations for copy.c functions from cache.h
server-info.h: move declarations for server-info.c functions from cache.h
packfile.h: move pack_window and pack_entry from cache.h
...
A small API fix to the ort merge strategy backend.
* en/ort-finalize-after-0-merges-fix:
merge-ort: fix calling merge_finalize() with no intermediate merge
If some code sets up the data structures for a merge, but then never
actually performs one before calling merge_finalize(), then
merge_finalize() wouldn't notice that result->priv was NULL and
return early, resulting in following that NULL pointer and getting
a segfault. There is currently no code in the git codebase that does
this, but this issue was found during testing of some proposed patches
that had the following structure:
struct merge_options merge_opt;
struct merge_result result;
init_merge_options(&merge_opt, the_repository);
memset(&result, 0, sizeof(result));
<do N merges, for some value of N>
merge_finalize(&merge_opt, &result);
where some flags could cause the code to have N=0, i.e. doing no merges.
Add a check for result->priv being NULL and return early to avoid a
segfault in these kinds of cases.
While at it, ensure the FREE_AND_NULL() in the function does something
useful with the nulling aspect, namely sets result->priv to NULL rather
than a mere temporary.
Reported-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Dozens of files made use of trace and trace2 functions, without
explicitly including trace.h or trace2.h. This made it more difficult
to find which files could remove a dependence on cache.h. Make C files
explicitly include trace.h or trace2.h if they are using them.
Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* ab/remove-implicit-use-of-the-repository:
libs: use "struct repository *" argument, not "the_repository"
post-cocci: adjust comments for recent repo_* migration
cocci: apply the "revision.h" part of "the_repository.pending"
cocci: apply the "rerere.h" part of "the_repository.pending"
cocci: apply the "refs.h" part of "the_repository.pending"
cocci: apply the "promisor-remote.h" part of "the_repository.pending"
cocci: apply the "packfile.h" part of "the_repository.pending"
cocci: apply the "pretty.h" part of "the_repository.pending"
cocci: apply the "object-store.h" part of "the_repository.pending"
cocci: apply the "diff.h" part of "the_repository.pending"
cocci: apply the "commit.h" part of "the_repository.pending"
cocci: apply the "commit-reach.h" part of "the_repository.pending"
cocci: apply the "cache.h" part of "the_repository.pending"
cocci: add missing "the_repository" macros to "pending"
cocci: sort "the_repository" rules by header
cocci: fix incorrect & verbose "the_repository" rules
cocci: remove dead rule from "the_repository.pending.cocci"
Apply the part of "the_repository.pending.cocci" pertaining to
"promisor-remote.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"object-store.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the part of "the_repository.pending.cocci" pertaining to
"commit-reach.h".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Dozens of files made use of gettext functions, without explicitly
including gettext.h. This made it more difficult to find which files
could remove a dependence on cache.h. Make C files explicitly include
gettext.h if they are using it.
However, while compat/fsmonitor/fsm-ipc-darwin.c should also gain an
include of gettext.h, it was left out to avoid conflicting with an
in-flight topic.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merging a branch with directory renames into a branch that changes
the directory to a symlink was mishandled by the ort merge
strategy, which has been corrected.
* en/ort-dir-rename-and-symlink-fix:
merge-ort: fix bug with dir rename vs change dir to symlink
More UNUSED annotation to help using -Wunused option with the
compiler.
* jk/unused-anno-more:
ll-merge: mark unused parameters in callbacks
diffcore-pickaxe: mark unused parameters in pickaxe functions
convert: mark unused parameter in null stream filter
apply: mark unused parameters in noop error/warning routine
apply: mark unused parameters in handlers
date: mark unused parameters in handler functions
string-list: mark unused callback parameters
object-file: mark unused parameters in hash_unknown functions
mark unused parameters in trivial compat functions
update-index: drop unused argc from do_reupdate()
submodule--helper: drop unused argc from module_list_compute()
diffstat_consume(): assert non-zero length
When changing a directory to a symlink on one side of history, and
renaming the parent of that directory to a different directory name
on the other side, e.g. with this kind of setup:
Base commit: Has a file named dir/subdir/file
Side1: Rename dir/ -> renamed-dir/
Side2: delete dir/subdir/file, add dir/subdir as symlink
Then merge-ort was running into an assertion failure:
git: merge-ort.c:2622: apply_directory_rename_modifications: Assertion `ci->dirmask == 0' failed
merge-recursive did not have as obvious an issue handling this case,
likely because we never fixed it to handle the case from commit
902c521a35 ("t6423: more involved directory rename test", 2020-10-15)
where we need to be careful about nested renames when a directory rename
occurs (dir/ -> renamed-dir/ implies dir/subdir/ ->
renamed-dir/subdir/). However, merge-recursive does have multiple
problems with this testcase:
* Incorrect stages for the file: merge-recursive omits the stage in
the index corresponding to the base stage, making `git status`
report "added by us" for renamed-dir/subdir/file instead of the
expected "deleted by them".
* Poor directory/file conflict handling: For the renamed-dir/subdir
symlink, instead of reporting a file/directory conflict as
expected, it reports "Error: Refusing to lose untracked file at
renamed-dir/subdir". This is a lie because there is no untracked
file at that location. It then does the normal suboptimal
merge-recursive thing of having the symlink be tracked in the index
at a location where it can't be written due to D/F conflicts
(namely, renamed-dir/subdir), but writes it to the working tree at
a different location as a new untracked file (namely,
renamed-dir/subdir~B^0)
Technically, these problems don't prevent the user from resolving the
merge if they can figure out to ignore the confusion, but because both
pieces of output are quite confusing I don't want to modify the test
to claim the recursive also passes it even if it doesn't have the bug
that ort did.
So, fix the bug in ort by splitting the conflict_info for "dir/subdir"
into two, one for the directory part, one for the file (i.e. symlink)
part, since the symlink is being renamed by directory rename detection.
The directory part is needed for proper nesting, since there are still
conflict_info fields for files underneath it (though those are marked
as is_null, they are still present until the entries are processed,
and the entry processing wants every non-toplevel entry to have a
parent directory).
Reported-by: Stefano Rivera <stefano@rivera.za.net>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
String-lists may be used with callbacks for clearing or iteration. These
callbacks need to conform to a particular interface, even though not
every callback needs all of its parameters. Mark the unused ones to make
-Wunused-parameter happy.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the previous commit, we fixed a segmentation fault when a tree object
could not be written.
However, before the tree object is written, `merge-ort` wants to write
out a blob object (except in cases where the merge results in a blob
that already exists in the database). And this can fail, too, but we
ignore that write failure so far.
Let's pay close attention and error out early if the blob could not be
written. This reduces the error output of t4301.25 ("merge-ort fails
gracefully in a read-only repository") from:
error: insufficient permission for adding an object to repository database ./objects
error: error: Unable to add numbers to database
error: insufficient permission for adding an object to repository database ./objects
error: error: Unable to add greeting to database
error: insufficient permission for adding an object to repository database ./objects
fatal: failure to merge
to:
error: insufficient permission for adding an object to repository database ./objects
error: error: Unable to add numbers to database
fatal: failure to merge
This is _not_ just a cosmetic change: Even though one might assume that
the operation would have failed anyway at the point when the new tree
object is written (and the corresponding tree object _will_ be new if it
contains a blob that is new), but that is not so: As pointed out by
Elijah Newren, when Git has previously been allowed to add loose objects
via `sudo` calls, it is very possible that the blob object cannot be
written (because the corresponding `.git/objects/??/` directory may be
owned by `root`) but the tree object can be written (because the
corresponding objects directory is owned by the current user). This
would result in a corrupt repository because it is missing the blob
object, and with this here patch we prevent that.
Note: This patch adjusts two variable declarations from `unsigned` to
`int` because their purpose is to hold the return value of
`handle_content_merge()`, which is of type `int`. The existing users of
those variables are only interested whether that variable is zero or
non-zero, therefore this type change does not affect the existing code.
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If the blob/tree objects cannot be written, we really need the merge
operations to fail, and not to continue (and then try to access the tree
object which is however still set to `NULL`).
Let's stop ignoring the return value of `write_object_file()` and
`write_tree()` and set `clean = -1` in the error case.
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Further update the help messages given while merging submodules.
* en/submodule-merge-messages-fixes:
merge-ort: provide helpful submodule update message when possible
merge-ort: avoid surprise with new sub_flag variable
merge-ort: remove translator lego in new "submodule conflict suggestion"
submodule merge: update conflict error message
Commit 66b209b86a ("merge-ort: implement CE_SKIP_WORKTREE handling with
conflicted entries", 2021-03-20) added some code for merge-ort to handle
conflicted and skip_worktree entries in general. Included in this was
an ugly hack for dealing with present-despite-skipped entries and a
testcase (t6428.2) specific to that hack, since at that time users could
accidentally get files into that state when using a sparse checkout.
However, with the merging of 82386b4496 ("Merge branch
'en/present-despite-skipped'", 2022-03-09), that class of problems was
addressed globally and in a much cleaner way. As such, the
present-despite-skipped hack in merge-ort is no longer needed and can
simply be removed.
No additional testcase is needed here; t6428.2 was written to test the
necessary functionality and is being kept. The fact that this test
continues to pass despite the code being removed shows that the extra
code is no longer necessary.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In commit 4057523a40 ("submodule merge: update conflict error message",
2022-08-04), a more detailed message was provided when submodules
conflict, in order to help users know how to resolve those conflicts.
There were a couple situations for which a different message would be
more appropriate, but that commit left handling those for future work.
Unfortunately, that commit would check if any submodules were of the
type that it didn't know how to explain, and, if so, would avoid
providing the more detailed explanation even for the submodules it did
know how to explain.
Change this to have the code print the helpful messages for the subset
of submodules it knows how to explain.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 4057523a40 ("submodule merge: update conflict error message",
2022-08-04) added a sub_flag variable that is used to store a value from
enum conflict_and_info_types, but initializes it with a value of -1 that
does not correspond to any of the conflict_and_info_types. The code may
never set it to a valid value and yet still use it, which can be
surprising when reading over the code at first. Initialize it instead
to the generic CONFLICT_SUBMODULE_FAILED_TO_MERGE value, which is still
distinct from the two values we need to special case.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In commit 4057523a40 ("submodule merge: update conflict error message",
2022-08-04), the new "submodule conflict suggestion" code was
translating 6 different pieces of the new message and then used
carefully crafted logic to allow stitching it back together with special
formatting. Keep the components of the message together as much as
possible, so that:
* we reduce the number of things translators have to translate
* translators have more control over the format of the output
* the code is much easier for developers to understand too
Also, reformat some comments running beyond the 80th column while at it.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Plug memory leaks in the failure code path in the "merge-ort" merge
strategy backend.
* js/ort-clean-up-after-failed-merge:
merge-ort: do leave trace2 region even if checkout fails
merge-ort: clean up after failed merge
When attempting to merge in a superproject with conflicting submodule
pointers that cannot be fast-forwarded or trivially resolved, the merge
fails and Git prints an error message that accurately describes the
failure, but does not provide steps for the user to resolve the error.
Git is left in a conflicted state, which requires the user to:
1. merge submodules or update submodules to an already existing
commit that reflects the merge
2. add submodules changes to the superproject
3. finish merging superproject
These steps are non-obvious for newer submodule users to figure out
based on the error message and neither `git submodule status` nor `git
status` provide any useful pointers.
Update error message to provide steps to resolve submodule merge
conflict. Future work could involve adding an advice flag to the
message. Although the message is long, it also has the id of the
submodule commit that needs to be merged, which could be useful
information for the user.
Additionally, 5 merge failures that resulted in an early return have
been updated to reflect the status of the merge.
1. Null merge base (null o): CONFLICT_SUBMODULE_NULL_MERGE_BASE added
as a new conflict type and will print updated error message.
2. Null merge side a (null a): BUG(). See [1] for discussion
3. Null merge side b (null b): BUG(). See [1] for discussion
4. Submodule not checked out: added NEEDSWORK bit
5. Submodule commits not present: added NEEDSWORK bit
The errors with a NEEDSWORK bit deserve a more detailed explanation of
how to resolve them. See [2] for more context.
[1] https://lore.kernel.org/git/CABPp-BE0qGwUy80dmVszkJQ+tcpfLRW0OZyErymzhZ9+HWY1mw@mail.gmail.com/
[2] https://lore.kernel.org/git/xmqqpmhjjwo9.fsf@gitster.g/
Signed-off-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 557ac0350d (merge-ort: begin performance work; instrument with
trace2_region_* calls, 2021-01-23), we added Trace2 instrumentation, but
in the error path that returns early, we forgot to tell Trace2 that
we're leaving the region. Let's fix that.
Pointed-out-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 9fefce68dc (merge-ort: basic outline for merge_switch_to_result(),
2020-12-13), we added functionality to lay down the result of a merge on
disk. But we forgot to release the data structures in case
`unpack_trees()` failed to run properly.
This was pointed out by the `linux-leaks` job in our CI runs.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fixes a long-standing corner case bug around directory renames in
the merge-ort strategy.
* en/merge-dual-dir-renames-fix:
merge-ort: fix issue with dual rename and add/add conflict
merge-ort: shuffle the computation and cleanup of potential collisions
merge-ort: make a separate function for freeing struct collisions
merge-ort: small cleanups of check_for_directory_rename
t6423: add tests of dual directory rename plus add/add conflict
There is code in both merge-recursive and merge-ort for avoiding doubly
transitive renames (i.e. one side renames directory A/ -> B/, and the
other side renames directory B/ -> C/), because this combination would
otherwise make a mess for new files added to A/ on the first side and
wondering which directory they end up in -- especially if there were
even more renames such as the first side renaming C/ -> D/. In such
cases, it just turns "off" directory rename detection for the higher
order transitive cases.
The testcases added in t6423 a couple commits ago are slightly different
but similar in principle. They involve a similar case of paired
renaming but instead of A/ -> B/ and B/ -> C/, the second side renames
a leading directory of B/ to C/. And both sides add a new file
somewhere under the directory that the other side will rename. While
the new files added start within different directories and thus could
logically end up within different directories, it is weird for a file
on one side to end up where the other one started and not move along
with it. So, let's just turn off directory rename detection in this
case as well.
Another way to look at this is that if the source name involved in a
directory rename on one side is the target name of a directory rename
operation for a file from the other side, then we avoid the doubly
transitive rename. (More concretely, if a directory rename on side D
wants to rename a file on side E from OLD_NAME -> NEW_NAME, and side D
already had a file named NEW_NAME, and a directory rename on side E
wants to rename side D's NEW_NAME -> NEWER_NAME, then we turn off the
directory rename detection for NEW_NAME to prevent the
NEW_NAME -> NEWER_NAME rename, and instead end up with an add/add
conflict on NEW_NAME.)
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
