Simplify API implementation to delete references by eliminating
duplication.
* ps/ref-deletion-updates:
refs: remove `delete_refs` callback from backends
refs: deduplicate code to delete references
refs/files: use transactions to delete references
t5510: ensure that the packed-refs file needs locking
Newer versions of Getopt::Long started giving warnings against our
(ab)use of it in "git send-email". Bump the minimum version
requirement for Perl to 5.8.1 (from September 2002) to allow
simplifying our implementation.
* tz/send-email-negatable-options:
send-email: avoid duplicate specification warnings
perl: bump the required Perl version to 5.8.1 from 5.8.0
"git rebase --autosquash" is now enabled for non-interactive rebase,
but it is still incompatible with the apply backend.
* ak/rebase-autosquash:
rebase: rewrite --(no-)autosquash documentation
rebase: support --autosquash without -i
rebase: fully ignore rebase.autoSquash without -i
"git for-each-ref --no-sort" still sorted the refs alphabetically
which paid non-trivial cost. It has been redefined to show output
in an unspecified order, to allow certain optimizations to take
advantage of.
* vd/for-each-ref-unsorted-optimization:
t/perf: add perf tests for for-each-ref
ref-filter.c: use peeled tag for '*' format fields
for-each-ref: clean up documentation of --format
ref-filter.c: filter & format refs in the same callback
ref-filter.c: refactor to create common helper functions
ref-filter.c: rename 'ref_filter_handler()' to 'filter_one()'
ref-filter.h: add functions for filter/format & format-only
ref-filter.h: move contains caches into filter
ref-filter.h: add max_count and omit_empty to ref_format
ref-filter.c: really don't sort when using --no-sort
Test and shell scripts clean-up.
* ps/ban-a-or-o-operator-with-test:
Makefile: stop using `test -o` when unlinking duplicate executables
contrib/subtree: convert subtree type check to use case statement
contrib/subtree: stop using `-o` to test for number of args
global: convert trivial usages of `test <expr> -a/-o <expr>`
"git format-patch --encode-email-headers" ignored the option when
preparing the cover letter, which has been corrected.
* ss/format-patch-use-encode-headers-for-cover-letter:
format-patch: fix ignored encode_email_headers for cover letter
Update ref-related tests.
* ps/ref-tests-update:
t: mark several tests that assume the files backend with REFFILES
t7900: assert the absence of refs via git-for-each-ref(1)
t7300: assert exact states of repo
t4207: delete replace references via git-update-ref(1)
t1450: convert tests to remove worktrees via git-worktree(1)
t: convert tests to not access reflog via the filesystem
t: convert tests to not access symrefs via the filesystem
t: convert tests to not write references via the filesystem
t: allow skipping expected object ID in `ref-store update-ref`
"git add" and "git stash" learned to support the ":(attr:...)"
magic pathspec.
* jw/git-add-attr-pathspec:
attr: enable attr pathspec magic for git-add and git-stash
Code clean-up for jk/chunk-bounds topic.
* jk/chunk-bounds-more:
commit-graph: mark chunk error messages for translation
commit-graph: drop verify_commit_graph_lite()
commit-graph: check order while reading fanout chunk
commit-graph: use fanout value for graph size
commit-graph: abort as soon as we see a bogus chunk
commit-graph: clarify missing-chunk error messages
commit-graph: drop redundant call to "lite" verification
midx: check consistency of fanout table
commit-graph: handle overflow in chunk_size checks
The way CI testing used "prove" could lead to running the test
suite twice needlessly, which has been corrected.
* js/ci-discard-prove-state:
ci: avoid running the test suite _twice_
Add support for GitLab CI.
* ps/ci-gitlab:
ci: add support for GitLab CI
ci: install test dependencies for linux-musl
ci: squelch warnings when testing with unusable Git repo
ci: unify setup of some environment variables
ci: split out logic to set up failed test artifacts
ci: group installation of Docker dependencies
ci: make grouping setup more generic
ci: reorder definitions for grouping functions
Update the base topic to work with CMake builds.
* js/doc-unit-tests-with-cmake:
cmake: handle also unit tests
cmake: use test names instead of full paths
cmake: fix typo in variable name
artifacts-tar: when including `.dll` files, don't forget the unit-tests
unit-tests: do show relative file paths
unit-tests: do not mistake `.pdb` files for being executable
cmake: also build unit tests
Process to add some form of low-level unit tests has started.
* js/doc-unit-tests:
ci: run unit tests in CI
unit tests: add TAP unit test framework
unit tests: add a project plan document
"To dereference" and "to peel" were sometimes used in in-code
comments and documentation but without description in the glossary.
* vd/glossary-dereference-peel:
glossary: add definitions for dereference & peel
One parameter is called `file_pach`. On the face of it, this looks as if
it was supposed to talk about a `path` instead of a `pach`.
However, looking at the way this callback is called, it gets fed the
`d_name` from a directory entry, which provides just the file name, not
the full path. Therefore, let's fix this by calling the parameter
`file_name` instead.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that `refs_delete_refs` is implemented in a generic way via the ref
transaction interfaces there are no callers left that invoke the
`delete_refs` callback anymore. Remove it from all of our backends.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Both the files and the packed-refs reference backends now use the same
generic transactions-based code to delete references. Let's pull these
implementations up into `refs_delete_refs()` to deduplicate the code.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the `files_delete_refs()` callback function of the files backend we
implement deletion of references. This is done in two steps:
1. We lock the packed-refs file and delete all references from it in
a single transaction.
2. We delete all loose references via separate calls to
`refs_delete_ref()`.
These steps essentially duplicate the logic around locking and deletion
order that we already have in the transactional interfaces, where we do
know to lock and evict references from the packed-refs file. Despite the
fact that we duplicate the logic, it's also less efficient than if we
used a single generic transaction:
- The transactional interface knows to skip locking of the packed
refs in case they don't contain any of the refs which are about to
be deleted.
- We end up creating N+1 separate reference transactions, one for
the packed-refs file and N for the individual loose references.
Refactor the code to instead delete references via a single transaction.
As we don't assert the expected old object ID this is equivalent to the
previous behaviour, and we already do the same in the packed-refs
backend.
Despite the fact that the result is simpler to reason about, this change
also results in improved performance. The following benchmarks have been
executed in linux.git:
```
$ hyperfine -n '{rev}, packed={packed} refcount={refcount}' \
-L packed true,false -L refcount 1,1000 -L rev master,pks-ref-store-generic-delete-refs \
--setup 'git -C /home/pks/Development/git switch --detach {rev} && make -C /home/pks/Development/git -j17' \
--prepare 'printf "create refs/heads/new-branch-%d HEAD\n" $(seq {refcount}) | git -C /home/pks/Reproduction/linux.git update-ref --stdin && if test {packed} = true; then git pack-refs --all; fi' \
--warmup=10 \
'/home/pks/Development/git/bin-wrappers/git -C /home/pks/Reproduction/linux.git branch -d new-branch-{1..{refcount}}'
Benchmark 1: master packed=true refcount=1
Time (mean ± σ): 7.8 ms ± 1.6 ms [User: 3.4 ms, System: 4.4 ms]
Range (min … max): 5.5 ms … 11.0 ms 120 runs
Benchmark 2: master packed=false refcount=1
Time (mean ± σ): 7.0 ms ± 1.1 ms [User: 3.2 ms, System: 3.8 ms]
Range (min … max): 5.7 ms … 9.8 ms 180 runs
Benchmark 3: master packed=true refcount=1000
Time (mean ± σ): 283.8 ms ± 5.2 ms [User: 45.7 ms, System: 231.5 ms]
Range (min … max): 276.7 ms … 291.6 ms 10 runs
Benchmark 4: master packed=false refcount=1000
Time (mean ± σ): 284.4 ms ± 5.3 ms [User: 44.2 ms, System: 233.6 ms]
Range (min … max): 277.1 ms … 293.3 ms 10 runs
Benchmark 5: generic-delete-refs packed=true refcount=1
Time (mean ± σ): 6.2 ms ± 1.8 ms [User: 2.3 ms, System: 3.9 ms]
Range (min … max): 4.1 ms … 12.2 ms 142 runs
Benchmark 6: generic-delete-refs packed=false refcount=1
Time (mean ± σ): 7.1 ms ± 1.4 ms [User: 2.8 ms, System: 4.3 ms]
Range (min … max): 4.2 ms … 10.8 ms 157 runs
Benchmark 7: generic-delete-refs packed=true refcount=1000
Time (mean ± σ): 198.9 ms ± 1.7 ms [User: 29.5 ms, System: 165.7 ms]
Range (min … max): 196.1 ms … 201.4 ms 10 runs
Benchmark 8: generic-delete-refs packed=false refcount=1000
Time (mean ± σ): 199.7 ms ± 7.8 ms [User: 32.2 ms, System: 163.2 ms]
Range (min … max): 193.8 ms … 220.7 ms 10 runs
Summary
generic-delete-refs packed=true refcount=1 ran
1.14 ± 0.37 times faster than master packed=false refcount=1
1.15 ± 0.40 times faster than generic-delete-refs packed=false refcount=1
1.26 ± 0.44 times faster than master packed=true refcount=1
32.24 ± 9.17 times faster than generic-delete-refs packed=true refcount=1000
32.36 ± 9.29 times faster than generic-delete-refs packed=false refcount=1000
46.00 ± 13.10 times faster than master packed=true refcount=1000
46.10 ± 13.13 times faster than master packed=false refcount=1000
```
Especially in the case where we have many references we can see a clear
performance speedup of nearly 30%.
This is in contrast to the stated objecive in a27dcf89b6 (refs: make
delete_refs() virtual, 2016-09-04), where the virtual `delete_refs()`
function was introduced with the intent to speed things up rather than
making things slower. So it seems like we have outlived the need for a
virtual function.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
One of the tests in t5510 asserts that a `git fetch --prune` detects
failures to prune branches. This is done by locking the packed-refs
file, which would then later lead to a locking issue when Git tries to
rewrite the file to prune the branches from it.
Interestingly though, we do not pack the about-to-be-pruned branch into
the packed-refs file, so it never even contained that branch in the
first place. While this is good enough right now because the pruning
will always lock the file regardless of whether it contains the branch
or not, this is a mere implementation detail. In fact, we're about to
rewrite branch deletions to make use of the ref transaction interface,
which knows to skip rewrites of the packed-refs file in the case where
it does not contain the branches in the first place, and this will break
the test.
Prepare the test for that change by packing the refs before trying to
prune them.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A warning is issued for options which are specified more than once
beginning with perl-Getopt-Long >= 2.55. In addition to causing users
to see warnings, this results in test failures which compare the output.
An example, from t9001-send-email.37:
| +++ diff -u expect actual
| --- expect 2023-11-14 10:38:23.854346488 +0000
| +++ actual 2023-11-14 10:38:23.848346466 +0000
| @@ -1,2 +1,7 @@
| +Duplicate specification "no-chain-reply-to" for option "no-chain-reply-to"
| +Duplicate specification "to-cover|to-cover!" for option "to-cover"
| +Duplicate specification "cc-cover|cc-cover!" for option "cc-cover"
| +Duplicate specification "no-thread" for option "no-thread"
| +Duplicate specification "no-to-cover" for option "no-to-cover"
| fatal: longline.patch:35 is longer than 998 characters
| warning: no patches were sent
| error: last command exited with $?=1
| not ok 37 - reject long lines
Remove the duplicate option specs. These are primarily the explicit
'--no-' prefix opts which were added in f471494303 (git-send-email.perl:
support no- prefix with older GetOptions, 2015-01-30). This was done
specifically to support perl-5.8.0 which includes Getopt::Long 2.32[1].
Getopt::Long 2.33 added support for the '--no-' prefix natively by
appending '!' to the option specification string, which was included in
perl-5.8.1 and is not present in perl-5.8.0. The previous commit bumped
the minimum supported Perl version to 5.8.1 so we no longer need to
provide the '--no-' variants for negatable options manually.
Teach `--git-completion-helper` to output the '--no-' options. They are
not included in the options hash and would otherwise be lost.
Signed-off-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The following commit will make use of a Getopt::Long feature which is
only present in Perl >= 5.8.1. Document that as the minimum version we
support.
Many of our Perl scripts will continue to run with 5.8.0 but this change
allows us to adjust them as needed without breaking any promises to our
users.
The Perl requirement was last changed in d48b284183 (perl: bump the
required Perl version to 5.8 from 5.6.[21], 2010-09-24). At that time,
5.8.0 was 8 years old. It is now over 21 years old.
Signed-off-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add performance tests for 'for-each-ref'. The tests exercise different
combinations of filters/formats/options, as well as the overall performance
of 'git for-each-ref | git cat-file --batch-check' to demonstrate the
performance difference vs. 'git for-each-ref' with "%(*fieldname)" format
specifiers.
All tests are run against a repository with 40k loose refs - 10k commits,
each having a unique:
- branch
- custom ref (refs/custom/special_*)
- annotated tag pointing at the commit
- annotated tag pointing at the other annotated tag (i.e., a nested tag)
After those tests are finished, the refs are packed with 'pack-refs --all'
and the same tests are rerun.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In most builtins ('rev-parse <revision>^{}', 'show-ref --dereference'),
"dereferencing" a tag refers to a recursive peel of the tag object. Unlike
these cases, the dereferencing prefix ('*') in 'for-each-ref' format
specifiers triggers only a single, non-recursive dereference of a given tag
object. For most annotated tags, a single dereference is all that is needed
to access the tag's associated commit or tree; "recursive" and
"non-recursive" dereferencing are functionally equivalent in these cases.
However, nested tags (annotated tags whose target is another annotated tag)
dereferenced once return another tag, where a recursive dereference would
return the commit or tree.
Currently, if a user wants to filter & format refs and include information
about a recursively-dereferenced tag, they can do so with something like
'cat-file --batch-check':
git for-each-ref --format="%(objectname)^{} %(refname)" <pattern> |
git cat-file --batch-check="%(objectname) %(rest)"
But the combination of commands is inefficient. So, to improve the
performance of this use case and align the defererencing behavior of
'for-each-ref' with that of other commands, update the ref formatting code
to use the peeled tag (from 'peel_iterated_oid()') to populate '*' fields
rather than the tag's immediate target object (from 'get_tagged_oid()').
Additionally, add a test to 't6300-for-each-ref' to verify new nested tag
behavior and update 't6302-for-each-ref-filter.sh' to print the correct
value for nested dereferenced fields.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the description of the `*` prefix from the --format option
documentation to the part of the command documentation that deals with other
object type-specific modifiers. Also reorganize and reword the remaining
--format documentation so that the explanation of the default format doesn't
interrupt the details on format string interpolation.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update 'filter_and_format_refs()' to try to perform ref filtering &
formatting in a single ref iteration, without an intermediate 'struct
ref_array'. This can only be done if no operations need to be performed on a
pre-filtered array; specifically, if the refs are
- filtered on reachability,
- sorted, or
- formatted with ahead-behind information
they cannot be filtered & formatted in the same iteration. In that case,
fall back on the current filter-then-sort-then-format flow.
This optimization substantially improves memory usage due to no longer
storing a ref array in memory. In some cases, it also dramatically reduces
runtime (e.g. 'git for-each-ref --no-sort --count=1', which no longer loads
all refs into a 'struct ref_array' to printing only the first ref).
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Factor out parts of 'ref_array_push()', 'ref_filter_handler()', and
'filter_refs()' into new helper functions:
* Extract the code to grow a 'struct ref_array' and append a given 'struct
ref_array_item *' to it from 'ref_array_push()' into 'ref_array_append()'.
* Extract the code to filter a given ref by refname & object ID then create
a new 'struct ref_array_item *' from 'filter_one()' into
'apply_ref_filter()'.
* Extract the code for filter pre-processing, contains cache creation, and
ref iteration from 'filter_refs()' into 'do_filter_refs()'.
In later patches, these helpers will be used by new ref-filter API
functions. This patch does not result in any user-facing behavior changes or
changes to callers outside of 'ref-filter.c'.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename 'ref_filter_handler()' to 'filter_one()' to more clearly distinguish
it from other ref filtering callbacks that will be added in later patches.
The "*_one()" naming convention is common throughout the codebase for
iteration callbacks.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add two new public methods to 'ref-filter.h':
* 'print_formatted_ref_array()' which, given a format specification & array
of ref items, formats and prints the items to stdout.
* 'filter_and_format_refs()' which combines 'filter_refs()',
'ref_array_sort()', and 'print_formatted_ref_array()' into a single
function.
This consolidates much of the code used to filter and format refs in
'builtin/for-each-ref.c', 'builtin/tag.c', and 'builtin/branch.c', reducing
duplication and simplifying the future changes needed to optimize the filter
& format process.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the 'contains_cache' and 'no_contains_cache' used in filter_refs into
an 'internal' struct of the 'struct ref_filter'. In later patches, the
'struct ref_filter *' will be a common data structure across multiple
filtering functions. These caches are part of the common functionality the
filter struct will support, so they are updated to be internally accessible
wherever the filter is used.
The design used here mirrors what was introduced in 576de3d956
(unpack_trees: start splitting internal fields from public API, 2023-02-27)
for 'unpack_trees_options'.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add an internal 'array_opts' struct to 'struct ref_format' containing
formatting options that pertain to the formatting of an entire ref array:
'max_count' and 'omit_empty'. These values are specified by the '--count'
and '--omit-empty' options, respectively, to 'for-each-ref'/'tag'/'branch'.
Storing these values in the 'ref_format' will simplify the consolidation of
ref array formatting logic across builtins in later patches.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When '--no-sort' is passed to 'for-each-ref', 'tag', and 'branch', the
printed refs are still sorted by ascending refname. Change the handling of
sort options in these commands so that '--no-sort' to truly disables
sorting.
'--no-sort' does not disable sorting in these commands is because their
option parsing does not distinguish between "the absence of '--sort'"
(and/or values for tag.sort & branch.sort) and '--no-sort'. Both result in
an empty 'sorting_options' string list, which is parsed by
'ref_sorting_options()' to create the 'struct ref_sorting *' for the
command. If the string list is empty, 'ref_sorting_options()' interprets
that as "the absence of '--sort'" and returns the default ref sorting
structure (equivalent to "refname" sort).
To handle '--no-sort' properly while preserving the "refname" sort in the
"absence of --sort'" case, first explicitly add "refname" to the string list
*before* parsing options. This alone doesn't actually change any behavior,
since 'compare_refs()' already falls back on comparing refnames if two refs
are equal w.r.t all other sort keys.
Now that the string list is populated by default, '--no-sort' is the only
way to empty the 'sorting_options' string list. Update
'ref_sorting_options()' to return a NULL 'struct ref_sorting *' if the
string list is empty, and add a condition to 'ref_array_sort()' to skip the
sort altogether if the sort structure is NULL. Note that other functions
using 'struct ref_sorting *' do not need any changes because they already
ignore NULL values.
Finally, remove the condition around sorting in 'ls-remote', since it's no
longer necessary. Unlike 'for-each-ref' et. al., it does *not* do any
sorting by default. This default is preserved by simply leaving its sort key
string list empty before parsing options; if no additional sort keys are
set, 'struct ref_sorting *' is NULL and sorting is skipped.
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A few stray single quotes crept into the usage string in a2ce608244
(send-email docs: add format-patch options, 2021-10-25). Remove them.
Signed-off-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano