In git-diff, options like `-w` and `-I<regex>`, two files are considered
equivalent under the specified "ignore" rules, even when they are not
bit-for-bit identical. For options like `--raw`, `--name-status`,
and `--name-only`, git-diff deliberately compares only the SHA values
to determine whether two files are equivalent, for performance reasons.
As a result, a file shown in `git diff --name-status` may not appear
in `git diff --patch`.
To quickly determine whether two files are equivalent, add a helper
function diff_flush_patch_quietly() in diff.c. Add `.dry_run` field in
`struct diff_options`. When `.dry_run` is true, builtin_diff() returns
immediately upon finding any change. Call diff_flush_patch_quietly()
to determine if we should flush `--raw`, `--name-only` or `--name-status`
output.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Lidong Yan <yldhome2d2@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The reftable unit tests are now ported to the "clar" unit testing
framework.
* sk/reftable-clarify-tests:
t/unit-tests: finalize migration of reftable-related tests
t/unit-tests: convert reftable stack test to use clar
t/unit-tests: convert reftable record test to use clar
t/unit-tests: convert reftable readwrite test to use clar
t/unit-tests: convert reftable table test to use clar
t/unit-tests: convert reftable pq test to use clar
t/unit-tests: convert reftable merged test to use clar
t/unit-tests: convert reftable block test to use clar
t/unit-tests: convert reftable basics test to use clar test framework
t/unit-tests: implement clar specific reftable test helper functions
"git commit" that concludes a conflicted merge failed to notice and remove
existing comment added automatically (like "# Conflicts:") when the
core.commentstring is set to 'auto'.
* ac/auto-comment-char-fix:
config: set comment_line_str to "#" when core.commentChar=auto
commit: avoid scanning trailing comments when 'core.commentChar' is "auto"
The pop_most_recent_commit() function can have quite expensive
worst case performance characteristics, which has been optimized by
using prio-queue data structure.
* rs/pop-recent-commit-with-prio-queue:
commit: use prio_queue_replace() in pop_most_recent_commit()
prio-queue: add prio_queue_replace()
commit: convert pop_most_recent_commit() to prio_queue
GIT_TEST_INSTALLED was not honored in the recent topic related to
SHA256 hashes, which has been corrected.
* kl/test-installed-fix:
test-lib: respect GIT_TEST_INSTALLED when querying default hash
The old `lib-reftable.{c,h}` implemented helper functions for our
homegrown unit-testing framework. As part of migrating reftable-related
tests to the Clar framework, Clar-specific versions of these functions
in `lib-reftable-clar.{c,h}` were introduced.
Now that all test files using these helpers have been converted to Clar,
we can safely remove the original `lib-reftable.{c,h}` and rename the
Clar- specific versions back to `lib-reftable.{c,h}`. This restores a
clean and consistent naming scheme for shared test utilities.
Finally, update our build system to reflect the changes made and remove
redundant code related to the reftable tests and our old homegrown
unit-testing setup. `test-lib.{c,h}` remains unchanged in our build
system as some files particularly `t/helper/test-example-tap.c` depends
on it in order to run, and removing that would be beyond the scope of
this patch.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable stack test file to use clar by using clar assertions
where necessary.
This marks the end of all unit tests migrated away from the
`unit-tests/t-*.c` pattern, there are no longer any files matching that
glob. Remove the sanity check for `t-*.c` files to prevent Meson
configuration errors during CI and local builds.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable record test file to use clar by using clar assertions
where necessary.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable readwrite test file to use clar by using clar assertions
where necessary.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable table test file to use clar by using clar assertions
where necessary.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable priority queue test file to use clar by using clar
assertions where necessary.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable merged test file to use clar testing framework by using
clar assertions where necessary.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable block test file to use clar testing framework by using
clar assertions where necessary.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Adapt reftable basics test file to clar by using clar assertions
where necessary.Break up test edge case to improve modularity and
clarity.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Helper functions defined in `t/unit-tests/lib-reftable.{c,h}` are
required for the reftable-related test files to run. In the current
implementation these functions are designed to conform with our
homegrown unit-testing structure. So in other to convert the reftable
test files, there is need for a clar specific implementation of these
helper functions.
Implement equivalent helper functions in `lib-reftable-clar.{c,h}` to
use clar. These functions conform with the clar testing framework and
become available for all reftable-related test files implemented using
the clar testing framework, which requires them. This will be used by
subsequent commits.
Signed-off-by: Seyi Kuforiji <kuforiji98@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Clean up the way how signature on commit objects are exported to
and imported from fast-import stream.
* cc/fast-import-export-signature-names:
fast-(import|export): improve on commit signature output format
Lift the limitation to use changed-path filter in "git log" so that
it can be used for a pathspec with multiple literal paths.
* ly/changed-paths-traversal:
bloom: optimize multiple pathspec items in revision
revision: make helper for pathspec to bloom keyvec
bloom: replace struct bloom_key * with struct bloom_keyvec
bloom: rename function operates on bloom_key
bloom: add test helper to return murmur3 hash
find_cfg_ent() allocates a struct reflog_expire_entry_option via
FLEX_ALLOC_MEM and inserts it into a linked list in the
reflog_expire_options structure. The entries in this list are never
freed, resulting in a leak in cmd_reflog_expire and the gc reflog expire
maintenance task:
Direct leak of 39 byte(s) in 1 object(s) allocated from:
#0 0x7ff975ee6883 in calloc (/lib64/libasan.so.8+0xe6883)
#1 0x0000010edada in xcalloc ../wrapper.c:154
#2 0x000000df0898 in find_cfg_ent ../reflog.c:28
#3 0x000000df0898 in reflog_expire_config ../reflog.c:70
#4 0x00000095c451 in configset_iter ../config.c:2116
#5 0x0000006d29e7 in git_config ../config.h:724
#6 0x0000006d29e7 in cmd_reflog_expire ../builtin/reflog.c:205
#7 0x0000006d504c in cmd_reflog ../builtin/reflog.c:419
#8 0x0000007e4054 in run_builtin ../git.c:480
#9 0x0000007e4054 in handle_builtin ../git.c:746
#10 0x0000007e8a35 in run_argv ../git.c:813
#11 0x0000007e8a35 in cmd_main ../git.c:953
#12 0x000000441e8f in main ../common-main.c:9
#13 0x7ff9754115f4 in __libc_start_call_main (/lib64/libc.so.6+0x35f4)
#14 0x7ff9754116a7 in __libc_start_main@@GLIBC_2.34 (/lib64/libc.so.6+0x36a7)
#15 0x000000444184 in _start (/home/jekeller/libexec/git-core/git+0x444184)
Close this leak by adding a reflog_clear_expire_config() function which
iterates the linked list and frees its elements. Call it upon exit of
cmd_reflog_expire() and reflog_expire_condition().
Add a basic test which covers this leak. While at it, cover the
functionality from commit commit 3cb22b8efe (Per-ref reflog expiry
configuration, 2008-06-15). We've had this support for years, but lacked
any tests.
Co-developed-by: Jeff King <peff@peff.net>
Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a function to replace the top element of the queue that basically
does the same as prio_queue_get() followed by prio_queue_put(), but
without the work by prio_queue_get() to rebalance the heap. It can be
used to optimize loops that get one element and then immediately add
another one. That's common e.g., with commit history traversal, where
we get out a commit and then put in its parents.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
pop_most_recent_commit() calls commit_list_insert_by_date() for parent
commits, which is itself called in a loop. This can lead to quadratic
complexity if there are many merges. Replace the commit_list with a
prio_queue to ensure logarithmic worst case complexity and convert all
three users.
Add a performance test that exercises one of them using a pathological
history that consists of 50% merges and 50% root commits to demonstrate
the speedup:
Test v2.50.1 HEAD
----------------------------------------------------------------------
1501.2: rev-parse ':/65535' 2.48(2.47+0.00) 0.20(0.19+0.00) -91.9%
Alas, sane histories don't benefit from the conversion much, and
traversing Git's own history takes a 1% performance hit on my machine:
$ hyperfine -w3 -L git ./git_2.50.1,./git '{git} rev-parse :/^Initial.revision'
Benchmark 1: ./git_2.50.1 rev-parse :/^Initial.revision
Time (mean ± σ): 1.071 s ± 0.004 s [User: 1.052 s, System: 0.017 s]
Range (min … max): 1.067 s … 1.078 s 10 runs
Benchmark 2: ./git rev-parse :/^Initial.revision
Time (mean ± σ): 1.079 s ± 0.003 s [User: 1.060 s, System: 0.017 s]
Range (min … max): 1.074 s … 1.083 s 10 runs
Summary
./git_2.50.1 rev-parse :/^Initial.revision ran
1.01 ± 0.00 times faster than ./git rev-parse :/^Initial.revision
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git uses `rebase.autostash` or `merge.autostash` to determine whether a
dirty worktree is allowed during pull. However, this behavior is not
clearly documented, making it difficult for users to discover how to
enable autostash, or causing them to unknowingly enable it. Add new
config option `pull.autostash` along with its documentation and test
cases.
`pull.autostash` provides the same functionality as `rebase.autostash`
and `merge.autostash`, but overrides them when set. If `pull.autostash`
is not set, it falls back to `rebase.autostash` or `merge.autostash`,
depending on the value of `pull.rebase`.
Signed-off-by: Lidong Yan <yldhome2d2@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git remote" now detects remote names that overlap with each other
(e.g., remote nickname "outer" and "outer/inner" are used at the
same time), as it will lead to overlapping remote-tracking
branches.
* jk/remote-avoid-overlapping-names:
remote: detect collisions in remote names
"pack-objects" has been taught to avoid pointing into objects in
cruft packs from midx.
* tb/midx-avoid-cruft-packs:
repack: exclude cruft pack(s) from the MIDX where possible
pack-objects: introduce '--stdin-packs=follow'
pack-objects: swap 'show_{object,commit}_pack_hint'
pack-objects: fix typo in 'show_object_pack_hint()'
pack-objects: perform name-hash traversal for unpacked objects
pack-objects: declare 'rev_info' for '--stdin-packs' earlier
pack-objects: factor out handling '--stdin-packs'
pack-objects: limit scope in 'add_object_entry_from_pack()'
pack-objects: use standard option incompatibility functions
Prepare to flip the default hash function to SHA-256.
* bc/use-sha256-by-default-in-3.0:
Enable SHA-256 by default in breaking changes mode
help: add a build option for default hash
t5300: choose the built-in hash outside of a repo
t4042: choose the built-in hash outside of a repo
t1007: choose the built-in hash outside of a repo
t: default to compile-time default hash if not set
setup: use the default algorithm to initialize repo format
Use legacy hash for legacy formats
builtin: use default hash when outside a repository
hash: add a constant for the legacy hash algorithm
hash: add a constant for the default hash algorithm
Define .precision to more canned parse-options type to avoid bugs
coming from using a variable with a wrong type to capture the
parsed values.
* rs/parse-options-precision:
parse-options: add precision handling for OPTION_COUNTUP
parse-options: add precision handling for OPTION_BITOP
parse-options: add precision handling for OPTION_NEGBIT
parse-options: add precision handling for OPTION_BIT
parse-options: add precision handling for OPTION_SET_INT
parse-options: add precision handling for PARSE_OPT_CMDMODE
parse-options: require PARSE_OPT_NOARG for OPTION_BITOP
When a ref creation at refs/heads/foo/bar fails, the files backend
now removes refs/heads/foo/ if the directory is otherwise not used.
* ps/refs-files-remove-empty-parent:
refs/files: remove empty parent dirs when ref creation fails
When core.commentChar is set to "auto", Git selects a comment character
by scanning the commit message contents and avoiding any character
already present in the message.
If the message still contains old conflict comments (starting with a
comment character), Git assumes that character is in use and chooses a
different one. As a result, those existing comment lines are no longer
recognized as comments and end up being included in the final commit
message.
To avoid this, skip scanning the trailing comment block when selecting
the comment character. This allows Git to safely reuse the original
character when appropriate, keeping the commit message clean and free of
leftover conflict information.
Background:
The "auto" value for core.commentchar was introduced in the commit
84c9dc2c5a (commit: allow core.commentChar=auto for character auto
selection, 2014-05-17) but did not exhibit this issue at that time.
The bug was introduced in commit a6c2654f83 (rebase -m: fix --signoff
with conflicts, 2024-04-18) where Git started writing conflict comments
to the file at 'rebase_path_message()'.
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
Signed-off-by: Ayush Chandekar <ayu.chandekar@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Leakfix with a new and a bit invasive test.
* ly/load-bitmap-leakfix:
pack-bitmap: add load corrupt bitmap test
pack-bitmap: reword comments in test_bitmap_commits()
pack-bitmap: fix memory leak if load_bitmap() failed
Code clean-up around object access API.
* ps/object-store:
odb: rename `read_object_with_reference()`
odb: rename `pretend_object_file()`
odb: rename `has_object()`
odb: rename `repo_read_object_file()`
odb: rename `oid_object_info()`
odb: trivial refactorings to get rid of `the_repository`
odb: get rid of `the_repository` when handling submodule sources
odb: get rid of `the_repository` when handling the primary source
odb: get rid of `the_repository` in `for_each()` functions
odb: get rid of `the_repository` when handling alternates
odb: get rid of `the_repository` in `odb_mkstemp()`
odb: get rid of `the_repository` in `assert_oid_type()`
odb: get rid of `the_repository` in `find_odb()`
odb: introduce parent pointers
object-store: rename files to "odb.{c,h}"
object-store: rename `object_directory` to `odb_source`
object-store: rename `raw_object_store` to `object_database`
$GIT_TEST_INSTALLED can be set to use an "installed" git instead of the
one from $GIT_BUILD_DIR. This is used by my company's internal test
infrastructure, and not using $GIT_TEST_INSTALLED when querying the
default hash meant that the tests were failing because the hash was
effectively set to the empty string (since git didn't execute).
In the two places we attempt to detect/execute git itself prior to
overriding everything and putting it in $PATH, use identical logic for
identifying the git binary to execute. This also has the effect of
including the $X suffix when querying the default hash, but that's not
strictly necessary. You don't need to specify .exe when running a binary
on Windows, just when testing whether it exists or not.
Signed-off-by: Kyle Lippincott <spectral@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To enable optimize multiple pathspec items in revision traversal,
return 0 if all pathspec item is literal in forbid_bloom_filters().
Add for loops to initialize and check each pathspec item's bloom_keyvec
when optimization is possible.
Add new test cases in t/t4216-log-bloom.sh to ensure
- consistent results between the optimization for multiple pathspec
items using bloom filter and the case without bloom filter
optimization.
- does not use bloom filter if any pathspec item is not literal.
With these optimizations, we get some improvements for multi-pathspec runs
of 'git log'. First, in the Git repository we see these modest results:
Benchmark 1: old
Time (mean ± σ): 73.1 ms ± 2.9 ms
Range (min … max): 69.9 ms … 84.5 ms 42 runs
Benchmark 2: new
Time (mean ± σ): 55.1 ms ± 2.9 ms
Range (min … max): 51.1 ms … 61.2 ms 52 runs
Summary
'new' ran
1.33 ± 0.09 times faster than 'old'
But in a larger repo, such as the LLVM project repo below, we get even
better results:
Benchmark 1: old
Time (mean ± σ): 1.974 s ± 0.006 s
Range (min … max): 1.960 s … 1.983 s 10 runs
Benchmark 2: new
Time (mean ± σ): 262.9 ms ± 2.4 ms
Range (min … max): 257.7 ms … 266.2 ms 11 runs
Summary
'new' ran
7.51 ± 0.07 times faster than 'old'
Signed-off-by: Derrick Stolee <stolee@gmail.com>
[ly: rename convert_pathspec_to_filter() to convert_pathspec_to_bloom_keyvec()]
Signed-off-by: Lidong Yan <502024330056@smail.nju.edu.cn>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git apply -N" should start from the current index and register
only new files, but it instead started from an empty index, which
has been corrected.
* rp/apply-intent-to-add-fix:
apply docs: clarify wording for --intent-to-add
t4140: test apply --intent-to-add interactions
apply: only write intents to add for new files
apply: read in the index in --intent-to-add mode
Code and test clean-up around string-list API.
* sj/string-list:
u-string-list: move "remove duplicates" test to "u-string-list.c"
u-string-list: move "filter string" test to "u-string-list.c"
u-string-list: move "test_split_in_place" to "u-string-list.c"
u-string-list: move "test_split" into "u-string-list.c"
string-list: enable sign compare warnings check
string-list: return index directly when inserting an existing element
string-list: remove unused "insert_at" parameter from add_entry
string-list: fix sign compare warnings for loop iterator
Tempfile removal fix in the codepath to sign commits with SSH keys.
* re/ssh-sign-buffer-fix:
ssh signing: don't detach the filename strbuf from key_file tempfile
A failure to open the index file for writing due to conflicting
access did not state what went wrong, which has been corrected.
* hy/read-cache-lock-error-fix:
read-cache: report lock error when refreshing index
"netrc" credential helper has been improved to understand textual
service names (like smtp) in addition to the numeric port numbers
(like 25).
* mc/netrc-service-names:
contrib: better support symbolic port names in git-credential-netrc
contrib: warn for invalid netrc file ports in git-credential-netrc
contrib: use a more portable shebang for git-credential-netrc
The reftable ref backend has matured enough; Git 3.0 will make it
the default format in a newly created repositories by default.
* ps/use-reftable-as-default-in-3.0:
setup: use "reftable" format when experimental features are enabled
BreakingChanges: announce switch to "reftable" format
A diff-filter with negative-only specification like "git log
--diff-filter=d" did not trigger correctly, which has been fixed.
* jk/all-negative-diff-filter-fix:
setup_revisions(): turn on diffs for all-negative diff filter
Some code paths in the "git prune" used to ignore passed in
repository object and used the_repository singleton instance
instead, which has been corrected.
* ac/prune-wo-the-repository:
builtin/prune: stop depending on 'the_repository'
repository: move 'repository_format_precious_objects' to repo scope
git code style requires that functions operating on a struct S
should be named in the form S_verb. However, the functions operating
on struct bloom_key do not follow this convention. Therefore,
fill_bloom_key() and clear_bloom_key() are renamed to bloom_key_fill()
and bloom_key_clear(), respectively.
Signed-off-by: Lidong Yan <502024330056@smail.nju.edu.cn>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In bloom.h, murmur3_seeded_v2() is exported for the use of test murmur3
hash. To clarify that murmur3_seeded_v2() is exported solely for testing
purposes, a new helper function test_murmur3_seeded() was added instead
of exporting murmur3_seeded_v2() directly.
Signed-off-by: Lidong Yan <502024330056@smail.nju.edu.cn>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A recent commit, d9cb0e6ff8 (fast-export, fast-import: add support for
signed-commits, 2025-03-10), added support for signed commits to
fast-export and fast-import.
When a signed commit is processed, fast-export can output either
"gpgsig sha1" or "gpgsig sha256" depending on whether the signed
commit uses the SHA-1 or SHA-256 Git object format.
However, this implementation has a number of limitations:
- the output format was not properly described in the documentation,
- the output format is not very informative as it doesn't even say
if the signature is an OpenPGP, an SSH, or an X509 signature,
- the implementation doesn't support having both one signature on
the SHA-1 object and one on the SHA-256 object.
Let's improve on these limitations by improving fast-export and
fast-import so that:
- all the signatures are exported,
- at most one signature on the SHA-1 object and one on the SHA-256
are imported,
- if there is more than one signature on the SHA-1 object or on
the SHA-256 object, fast-import emits a warning for each
additional signature,
- the output format is "gpgsig <git-hash-algo> <signature-format>",
where <git-hash-algo> is the Git object format as before, and
<signature-format> is the signature type ("openpgp", "x509",
"ssh" or "unknown"),
- the output is properly documented.
About the output format:
- <git-hash-algo> allows to know which representation of the commit
was signed (the SHA-1 or the SHA-256 version) which helps with
both signature verification and interoperability between repos
with different hash functions,
- <signature-format> helps tools that process the fast-export
stream, so they don't have to parse the ASCII armor to identify
the signature type.
It could be even better to be able to import more than one signature
on the SHA-1 object and on the SHA-256 object, but other parts of
Git don't handle that well for now, so this is left for future
improvements.
Helped-by: brian m. carlson <sandals@crustytoothpaste.net>
Helped-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Similar to 09705696f7 (parse-options: introduce precision handling for
`OPTION_INTEGER`, 2025-04-17) support value variables of different sizes
for OPTION_COUNTUP. Do that by requiring their "precision" to be set,
casting their "value" pointer accordingly and checking whether the value
fits.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Similar to 09705696f7 (parse-options: introduce precision handling for
`OPTION_INTEGER`, 2025-04-17) support value variables of different sizes
for OPTION_SET_INT. Do that by requiring their "precision" to be set,
casting their "value" pointer accordingly and checking whether the value
fits.
Factor out the casting code from the part of do_get_value() that handles
OPTION_INTEGER to avoid code duplication. We're going to use it in the
next patches as well.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Build on 09705696f7 (parse-options: introduce precision handling for
`OPTION_INTEGER`, 2025-04-17) to support value variables of different
sizes for PARSE_OPT_CMDMODE options. Do that by requiring their
"precision" to be set and casting their "value" pointer accordingly.
Call the function that does the raw casting do_get_int_value() to
reserve the name get_int_value() for a more friendly wrapper we're
going to introduce in one of the next patches.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When two remotes collide in the destinations of their fetch refspecs,
the results can be confusing. For example, in this silly example:
git config remote.one.url [...]
git config remote.one.fetch +refs/heads/*:refs/remotes/collide/*
git config remote.two.url [...]
git config remote.two.fetch +refs/heads/*:refs/remotes/collide/*
git fetch --all
we may try to write to the same ref twice (once for each remote we're
fetching). There's also a more subtle version of this. If you have
remotes "outer/inner" and "outer", then the ref "inner/branch" on the
second remote will conflict with just "branch" on the former (they both
want to write to "refs/remotes/outer/inner/branch").
We probably don't want to forbid this kind of overlap completely. While
the results can be confusing, there are legitimate reasons to have
multiple refs write into the same namespace (e.g., if one is a "backup"
of the other that is rarely fetched from).
But it may be worth limiting the porcelain "git remote" command to avoid
this confusion. The example above cannot be done with "git remote",
because it always[1] matches the refspecs to the remote name, and you
can only have one instance of each remote name. But you can still
trigger the more subtle variant like this:
git remote add outer [...]
git remote add outer/inner [...]
So let's detect that kind of name collision (in both directions) and
forbid it. You can still do whatever you like by manipulating the config
directly, but this should prevent the most obvious foot-gun.
[1] Almost always. With the --mirror option, the resulting refspec will
just write into "refs/*"; the remote name does not appear in the ref
namespace at all.
Our new "names must not overlap" rule is not necessary for that
case, but it seems reasonable to enforce it consistently. We already
require all remote names to be valid in the ref namespace, even
though we won't ever use them in that context for --mirror remotes.
Likewise, our new rule doesn't help with overlap here. Any two
mirror remotes will always overlap (in fact, any mirror remote along
with any other single one, since refs/remotes/ is a subset of the
mirrored refs). I'm not sure this is worth worrying about, but if it
is, we'd want an additional rule like "mirror remotes must be the
only remote".
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
