Remove remnants of the recursive merge strategy backend, which was
superseded by the ort merge strategy.
* en/merge-recursive-debug:
builtin/{merge,rebase,revert}: remove GIT_TEST_MERGE_ALGORITHM
tests: remove GIT_TEST_MERGE_ALGORITHM and test_expect_merge_algorithm
merge-recursive.[ch]: thoroughly debug these
merge, sequencer: switch recursive merges over to ort
sequencer: switch non-recursive merges over to ort
merge-ort: enable diff-algorithms other than histogram
builtin/merge-recursive: switch to using merge_ort_generic()
checkout: replace merge_trees() with merge_ort_nonrecursive()
"git blame --porcelain" mode now talks about unblamable lines and
lines that are blamed to an ignored commit.
* kn/blame-porcelain-unblamable:
blame: print unblamable and ignored commits in porcelain mode
"git fetch [<remote>]" with only the configured fetch refspec
should be the only thing to update refs/remotes/<remote>/HEAD,
but the code was overly eager to do so in other cases.
* jk/fetch-follow-remote-head-fix:
fetch: make set_head() call easier to read
fetch: don't ask for remote HEAD if followRemoteHEAD is "never"
fetch: only respect followRemoteHEAD with configured refspecs
"git cat-file --batch" and friends learned to allow "--filter=" to
omit certain objects, just like the transport layer does.
* ps/cat-file-filter-batch:
builtin/cat-file: use bitmaps to efficiently filter by object type
builtin/cat-file: deduplicate logic to iterate over all objects
pack-bitmap: introduce function to check whether a pack is bitmapped
pack-bitmap: add function to iterate over filtered bitmapped objects
pack-bitmap: allow passing payloads to `show_reachable_fn()`
builtin/cat-file: support "object:type=" objects filter
builtin/cat-file: support "blob:limit=" objects filter
builtin/cat-file: support "blob:none" objects filter
builtin/cat-file: wire up an option to filter objects
builtin/cat-file: introduce function to report object status
builtin/cat-file: rename variable that tracks usage
Updating multiple references have only been possible in all-or-none
fashion with transactions, but it can be more efficient to batch
multiple updates even when some of them are allowed to fail in a
best-effort manner. A new "best effort batches of updates" mode
has been introduced.
* kn/non-transactional-batch-updates:
update-ref: add --batch-updates flag for stdin mode
refs: support rejection in batch updates during F/D checks
refs: implement batch reference update support
refs: introduce enum-based transaction error types
refs/reftable: extract code from the transaction preparation
refs/files: remove duplicate duplicates check
refs: move duplicate refname update check to generic layer
refs/files: remove redundant check in split_symref_update()
"git rev-list" learns machine-parsable output format that delimits
each field with NUL.
* jt/rev-list-z:
rev-list: support NUL-delimited --missing option
rev-list: support NUL-delimited --boundary option
rev-list: support delimiting objects with NUL bytes
rev-list: refactor early option parsing
rev-list: inline `show_object_with_name()` in `show_object()`
Code clean-up.
* js/comma-semicolon-confusion:
detect-compiler: detect clang even if it found CUDA
clang: warn when the comma operator is used
compat/regex: explicitly mark intentional use of the comma operator
wildmatch: avoid using of the comma operator
diff-delta: avoid using the comma operator
xdiff: avoid using the comma operator unnecessarily
clar: avoid using the comma operator unnecessarily
kwset: avoid using the comma operator unnecessarily
rebase: avoid using the comma operator unnecessarily
remote-curl: avoid using the comma operator unnecessarily
"git clone" still gave the message about the default branch name;
this message has been turned into an advice message that can be
turned off.
* jt/clone-guess-remote-head-fix:
advice: allow disabling default branch name advice
builtin/clone: suppress unexpected default branch advice
remote: allow `guess_remote_head()` to suppress advice
The job to coalesce loose objects into packfiles in "git
maintenance" now has configurable batch size.
* ds/maintenance-loose-objects-batchsize:
maintenance: add loose-objects.batchSize config
maintenance: force progress/no-quiet to children
"git reflog" learns "drop" subcommand, that discards the entire
reflog data for a ref.
* kn/reflog-drop:
reflog: implement subcommand to drop reflogs
reflog: improve error for when reflog is not found
The object layer has been updated to take an explicit repository
instance as a parameter in more code paths.
* ps/object-wo-the-repository:
hash: stop depending on `the_repository` in `null_oid()`
hash: fix "-Wsign-compare" warnings
object-file: split out logic regarding hash algorithms
delta-islands: stop depending on `the_repository`
object-file-convert: stop depending on `the_repository`
pack-bitmap-write: stop depending on `the_repository`
pack-revindex: stop depending on `the_repository`
pack-check: stop depending on `the_repository`
environment: move access to "core.bigFileThreshold" into repo settings
pack-write: stop depending on `the_repository` and `the_hash_algo`
object: stop depending on `the_repository`
csum-file: stop depending on `the_repository`
We ignore any error returned from set_head(), but 638060dcb9 (fetch
set_head: refactor to use remote directly, 2025-01-26) left its call in
a noop "if" conditional as a sort of note-to-self.
When c834d1a7ce (fetch: only respect followRemoteHEAD with configured
refspecs, 2025-03-18) added a "do_set_head" flag, it was rolled into the
same conditional, putting set_head() on the right-hand side of a
short-circuit AND.
That's not wrong, but it really hides the point of the line, which
is (maybe) calling the function.
Instead, let's have a full if() block for the flag, and then our comment
(with some rewording) will be sufficient to clarify the error handling.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since we already teach the `repo_config()` in f29f1990 (config:
teach repo_config to allow `repo` to be NULL, 2025-03-08) to allow
`repo` to be NULL, no need to check if `repo` is NULL before calling
`repo_config()`.
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This environment variable existed to allow the testsuite 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. Remove it from these three builtins.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More precisely, replace calls to merge_recursive() with
merge_ort_recursive().
Also change t7615 to quit calling out recursive; it is not needed
anymore, and we are in fact using ort now.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
Replace the use of merge_trees() from merge-recursive.[ch] with the
merge-ort equivalent.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Incrementally updating multi-pack index files.
* tb/incremental-midx-part-2:
midx: implement writing incremental MIDX bitmaps
pack-bitmap.c: use `ewah_or_iterator` for type bitmap iterators
pack-bitmap.c: keep track of each layer's type bitmaps
ewah: implement `struct ewah_or_iterator`
pack-bitmap.c: apply pseudo-merge commits with incremental MIDXs
pack-bitmap.c: compute disk-usage with incremental MIDXs
pack-bitmap.c: teach `rev-list --test-bitmap` about incremental MIDXs
pack-bitmap.c: support bitmap pack-reuse with incremental MIDXs
pack-bitmap.c: teach `show_objects_for_type()` about incremental MIDXs
pack-bitmap.c: teach `bitmap_for_commit()` about incremental MIDXs
pack-bitmap.c: open and store incremental bitmap layers
pack-revindex: prepare for incremental MIDX bitmaps
Documentation: describe incremental MIDX bitmaps
Documentation: remove a "future work" item from the MIDX docs
When updating multiple references through stdin, Git's update-ref
command normally aborts the entire transaction if any single update
fails. This atomic behavior prevents partial updates. Introduce a new
batch update system, where the updates the performed together similar
but individual updates are allowed to fail.
Add a new `--batch-updates` flag that allows the transaction to continue
even when individual reference updates fail. This flag can only be used
in `--stdin` mode and builds upon the batch update support added to the
refs subsystem in the previous commits. When enabled, failed updates are
reported in the following format:
rejected SP (<old-oid> | <old-target>) SP (<new-oid> | <new-target>) SP <rejection-reason> LF
Update the documentation to reflect this change and also tests to cover
different scenarios where an update could be rejected.
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Acked-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Replace preprocessor-defined transaction errors with a strongly-typed
enum `ref_transaction_error`. This change:
- Improves type safety and function signature clarity.
- Makes error handling more explicit and discoverable.
- Maintains existing error cases, while adding new error cases for
common scenarios.
This refactoring paves the way for more comprehensive error handling
which we will utilize in the upcoming commits to add batch reference
update support.
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Acked-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
By default, git-maintenance(1) uses the "gc" task to ensure that the
repository is well-maintained. This can be changed, for example by
either explicitly configuring which tasks should be enabled or by using
the "incremental" maintenance strategy. If so, git-maintenance(1) does
not know to expire reflog entries, which is a subtask that git-gc(1)
knows to perform for the user. Consequently, the reflog will grow
indefinitely unless the user manually trims it.
Introduce a new "reflog-expire" task that plugs this gap:
- When running the task directly, then we simply execute `git reflog
expire --all`, which is the same as git-gc(1).
- When running git-maintenance(1) with the `--auto` flag, then we only
run the task in case the "HEAD" reflog has at least N reflog entries
that would be discarded. By default, N is set to 100, but this can
be configured via "maintenance.reflog-expire.auto". When a negative
integer has been provided we always expire entries, zero causes us
to never expire entries, and a positive value specifies how many
entries need to exist before we consider pruning the entries.
Note that the condition for the `--auto` flags is merely a heuristic and
optimized for being fast. This is because `git maintenance run --auto`
will be executed quite regularly, so scanning through all reflogs would
likely be too expensive in many repositories.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We're about to introduce a new task for git-maintenance(1) that knows to
expire reflog entries. The logic will be shared with git-gc(1), which
already knows how to do this.
Pull out the common logic into a separate function so that we can share
the implementation between both builtins.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Make functions that are required to manage `reflog_expire_options`
available elsewhere by moving them into "reflog.c" and exposing them in
the corresponding header. The functions will be used in a subsequent
commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
As described in the preceding commit, the per-reflog expiry dates are
stored in a global pair of variables. Refactor the code so that they are
contained in `struct reflog_expire_options` to make the structure useful
in other contexts.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When expiring reflog entries, it is possible to configure expiry dates
that depend on the name of the reflog. This requires us to store a
couple of different expiry dates:
- The default expiry date for reflog entries that aren't otherwise
specified.
- The per-reflog expiry date.
- The currently active set of expiry dates for a given reference.
While the last item is stored in `struct reflog_expire_options`, the
other items aren't, which makes it hard to reuse the structure in other
places.
Refactor the code so that the default expiry date is stored as part of
the structure. The per-reflog expiry dates will be adapted accordingly
in the subsequent commit.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We're about to expose `struct cmd_reflog_expire_cb` via "reflog.h" so
that we can also use this structure in "builtin/gc.c". Once we make it
accessible to a wider scope though it becomes awkwardly named, as it
isn't only useful in the context of a callback. Instead, the function is
containing all kinds of options relevant to whether or not a reflog
entry should be expired.
Rename the structure to `reflog_expire_options` to prepare for this.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'git-blame(1)' command allows users to ignore specific revisions via
the '--ignore-rev <rev>' and '--ignore-revs-file <file>' flags. These
flags are often combined with the 'blame.markIgnoredLines' and
'blame.markUnblamableLines' config options. These config options prefix
ignored and unblamable lines with a '?' and '*', respectively.
However, this option was never extended to the porcelain mode of
'git-blame(1)'. Since the documentation does not indicate this
exclusion, it is a bug.
Fix this by printing 'ignored' and 'unblamable' respectively for the
options when using the porcelain modes.
Helped-by: Patrick Steinhardt <ps@pks.im>
Helped-by: Toon Claes <toon@iotcl.com>
Helped-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
While it is now possible to filter objects by type, this mechanism is
for now mostly a convenience. Most importantly, we still have to iterate
through the whole packfile to find all objects of a specific type. This
can be prohibitively expensive depending on the size of the packfiles.
It isn't really possible to do better than this when only considering a
packfile itself, as the order of objects is not fixed. But when we have
a packfile with a corresponding bitmap, either because the packfile
itself has one or because the multi-pack index has a bitmap for it, then
we can use these bitmaps to improve the runtime.
While bitmaps are typically used to compute reachability of objects,
they also contain one bitmap per object type that encodes which object
has what type. So instead of reading through the whole packfile(s), we
can use the bitmaps and iterate through the type-specific bitmap.
Typically, only a subset of packfiles will have a bitmap. But this isn't
really much of a problem: we can use bitmaps when available, and then
use the non-bitmap walk for every packfile that isn't covered by one.
Overall, this leads to quite a significant speedup depending on how many
objects of a certain type exist. The following benchmarks have been
executed in the Chromium repository, which has a 50GB packfile with
almost 25 million objects. As expected, there isn't really much of a
change in performance without an object filter:
Benchmark 1: cat-file with no-filter (revision = HEAD~)
Time (mean ± σ): 89.675 s ± 4.527 s [User: 40.807 s, System: 10.782 s]
Range (min … max): 83.052 s … 96.084 s 10 runs
Benchmark 2: cat-file with no-filter (revision = HEAD)
Time (mean ± σ): 88.991 s ± 2.488 s [User: 42.278 s, System: 10.305 s]
Range (min … max): 82.843 s … 91.271 s 10 runs
Summary
cat-file with no-filter (revision = HEAD) ran
1.01 ± 0.06 times faster than cat-file with no-filter (revision = HEAD~)
We still have to scan through all objects as we yield all of them, so
using the bitmap in this case doesn't really buy us anything. What is
noticeable in this benchmark is that we're I/O-bound, not CPU-bound, as
can be seen from the user/system runtimes, which combined are way lower
than the overall benchmarked runtime.
But when we do use a filter we can see a significant improvement:
Benchmark 1: cat-file with filter=object:type=commit (revision = HEAD~)
Time (mean ± σ): 86.444 s ± 4.081 s [User: 36.830 s, System: 11.312 s]
Range (min … max): 80.305 s … 93.104 s 10 runs
Benchmark 2: cat-file with filter=object:type=commit (revision = HEAD)
Time (mean ± σ): 2.089 s ± 0.015 s [User: 1.872 s, System: 0.207 s]
Range (min … max): 2.073 s … 2.119 s 10 runs
Summary
cat-file with filter=object:type=commit (revision = HEAD) ran
41.38 ± 1.98 times faster than cat-file with filter=object:type=commit (revision = HEAD~)
This is because we don't have to scan through all packfiles anymore, but
can instead directly look up relevant objects.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Pull out a common function that allows us to iterate over all objects in
a repository. Right now the logic is trivial and would only require two
function calls, making this refactoring a bit pointless. But in the next
commit we will iterate on this logic to make use of bitmaps, so this is
about to become a bit more complex.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `show_reachable_fn` callback is used by a couple of functions to
present reachable objects to the caller. The function does not provide a
way for the caller to pass a payload though, which is functionality that
we'll require in a subsequent commit.
Change the callback type to accept a payload and adapt all callsites
accordingly.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Implement support for the "object:type=" filter in git-cat-file(1),
which causes us to omit all objects that don't match the provided object
type.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Implement support for the "blob:limit=" filter in git-cat-file(1), which
causes us to omit all blobs that are bigger than a certain size.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Implement support for the "blob:none" filter in git-cat-file(1), which
causes us to omit all blobs.
Note that this new filter requires us to read the object type via
`oid_object_info_extended()` in `batch_object_write()`. But as we try to
optimize away reading objects from the database the `data->info.typep`
pointer may not be set. We thus have to adapt the logic to conditionally
set the pointer in cases where the filter is given.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In batch mode, git-cat-file(1) enumerates all objects and prints them
by iterating through both loose and packed objects. This works without
considering their reachability at all, and consequently most options to
filter objects as they exist in e.g. git-rev-list(1) are not applicable.
In some situations it may still be useful though to filter objects based
on properties that are inherent to them. This includes the object size
as well as its type.
Such a filter already exists in git-rev-list(1) with the `--filter=`
command line option. While this option supports a couple of filters that
are not applicable to our usecase, some of them are quite a neat fit.
Wire up the filter as an option for git-cat-file(1). This allows us to
reuse the same syntax as in git-rev-list(1) so that we don't have to
reinvent the wheel. For now, we die when any of the filter options has
been passed by the user, but they will be wired up in subsequent
commits.
Further note that the filters that we are about to introduce don't
significantly speed up the runtime of git-cat-file(1). While we can skip
emitting a lot of objects in case they are uninteresting to us, the
majority of time is spent reading the packfile, which is bottlenecked by
I/O and not the processor. This will change though once we start to make
use of bitmaps, which will allow us to skip reading the whole packfile.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have multiple callsites that report the status of an object, for
example when the objec tis missing or its name is ambiguous. We're about
to add a couple more such callsites to report on "excluded" objects.
Prepare for this by introducing a new function `report_object_status()`
that encapsulates the functionality.
Note that this function also flushes stdout, which is a requirement so
that request-response style batched modes can learn about the status
before proceeding to the next object. We already flush correctly at all
existing callsites, even though the flush in `batch_one_object()` only
comes after the switch statement. That flush is now redundant, and we
could in theory deduplicate it by moving it into all branches that don't
use `report_object_status()`. But that doesn't quite feel sensible:
- The duplicate flush should ultimately just be a no-op for us and
thus shouldn't impact performance significantly.
- By keeping the flush in `report_object_status()` we ensure that all
future callers get semantics correct.
So let's just be pragmatic and live with the duplicated flush.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The usage strings for git-cat-file(1) that we pass to `parse_options()`
and `usage_msg_optf()` are stored in a variable called `usage`. This
variable shadows the declaration of `usage()`, which we'll want to use
in a subsequent commit.
Rename the variable to `builtin_catfile_usage`, which is in line with
how the variable is typically called in other builtins.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An earlier code refactoring of the hash machinery missed a few
required calls to init_fn.
* jh/hash-init-fixes:
index-pack, unpack-objects: restore missing ->init_fn
Using "git name-rev --stdin" as an example, improve the framework to
prepare tests to pretend to be in the future where the breaking
changes have already happened.
* jc/name-rev-stdin:
name-rev: remove "--stdin" support
t6120: further modernize
t6120: avoid hiding "git" exit status
t: introduce WITH_BREAKING_CHANGES prerequisite
t: extend test_lazy_prereq
t: document test_lazy_prereq
There are multiple places in loops, where a signed and an
unsigned data type are compared. Git uses a mix of signed and unsigned
types to store lengths of arrays. This sometimes leads to using a signed
index for an array whose length is stored in an unsigned variable or
vice versa.
get_ours_cache_pos is a special case where i, though derived from a
signed variable is never negative. Move this part to the caller side
and make i an unsigned argument of the function. Rename i to
pos to make it descriptive, now that it is a function argument.
Replace signed data types with unsigned data types and vice versa
wherever necessary. Where both signed and unsigned data types have been
used, define a new variable in the scope of the for loop for use as the
iterator. Remove #define DISABLE_SIGN_COMPARE_WARNINGS.
Signed-off-by: Arnav Bhate <bhatearnav@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Miscellaneous code clean-ups.
* en/random-cleanups:
merge-ort: remove extraneous word in comment
merge-ort: fix accidental strset<->strintmap
t7615: be more explicit about diff algorithm used
t6423: fix a comment that accidentally reversed two commits
stash: remove merge-recursive.h include
Certain "cruft" objects would have never been refreshed when there
are multiple cruft packs in the repository, which has been
corrected.
* tb/multi-cruft-pack-refresh-fix:
builtin/pack-objects.c: freshen objects from existing cruft packs
In protocol v2 where the refs advertisement is constrained, we try
to tell the server side not to limit the advertisement when there
is no specific need to, which has been the source of confusion and
recent bugs. Revamp the logic to simplify.
* jk/fetch-ref-prefix-cleanup:
fetch: use ref prefix list to skip ls-refs
fetch: avoid ls-refs only to ask for HEAD symref update
fetch: stop protecting additions to ref-prefix list
fetch: ask server to advertise HEAD for config-less fetch
refspec_ref_prefixes(): clean up refspec_item logic
t5516: beef up exact-oid ref prefixes test
t5516: drop NEEDSWORK about v2 reachability behavior
t5516: prefer "oid" to "sha1" in some test titles
t5702: fix typo in test name
First step of deprecating and removing merge-recursive.
* en/merge-ort-prepare-to-remove-recursive:
am: switch from merge_recursive_generic() to merge_ort_generic()
merge-ort: fix merge.directoryRenames=false
t3650: document bug when directory renames are turned off
merge-ort: support having merge verbosity be set to 0
merge-ort: allow rename detection to be disabled
merge-ort: add new merge_ort_generic() function
The code paths to check whether a refname X is available (by seeing
if another ref X/Y exists, etc.) have been optimized.
* ps/refname-avail-check-optim:
refs: reuse iterators when determining refname availability
refs/iterator: implement seeking for files iterators
refs/iterator: implement seeking for packed-ref iterators
refs/iterator: implement seeking for ref-cache iterators
refs/iterator: implement seeking for reftable iterators
refs/iterator: implement seeking for merged iterators
refs/iterator: provide infrastructure to re-seek iterators
refs/iterator: separate lifecycle from iteration
refs: stop re-verifying common prefixes for availability
refs/files: batch refname availability checks for initial transactions
refs/files: batch refname availability checks for normal transactions
refs/reftable: batch refname availability checks
refs: introduce function to batch refname availability checks
builtin/update-ref: skip ambiguity checks when parsing object IDs
object-name: allow skipping ambiguity checks in `get_oid()` family
object-name: introduce `repo_get_oid_with_flags()`