Commit Graph

71680 Commits

Author SHA1 Message Date
8a5b2e1157 Merge branch 'hy/doc-show-is-like-log-not-diff-tree' into maint-2.42
Doc update.

* hy/doc-show-is-like-log-not-diff-tree:
  show doc: redirect user to git log manual instead of git diff-tree
2023-11-02 16:53:25 +09:00
965d445b2d Merge branch 'ch/clean-docfix' into maint-2.42
Typofix.

* ch/clean-docfix:
  git-clean doc: fix "without do cleaning" typo
2023-11-02 16:53:25 +09:00
905765bc5b Merge branch 'eg/config-type-path-docfix' into maint-2.42
Typofix.

* eg/config-type-path-docfix:
  git-config: fix misworded --type=path explanation
2023-11-02 16:53:25 +09:00
71c614b9a2 Merge branch 'ob/t3404-typofix' into maint-2.42
Code clean-up.

* ob/t3404-typofix:
  t3404-rebase-interactive.sh: fix typos in title of a rewording test
2023-11-02 16:53:24 +09:00
cd41f66b9d Merge branch 'ob/sequencer-remove-dead-code' into maint-2.42
Code clean-up.

* ob/sequencer-remove-dead-code:
  sequencer: remove unreachable exit condition in pick_commits()
2023-11-02 16:53:24 +09:00
f76827da0e Merge branch 'rs/name-rev-use-opt-hidden-bool' into maint-2.42
Simplify use of parse-options API a bit.

* rs/name-rev-use-opt-hidden-bool:
  name-rev: use OPT_HIDDEN_BOOL for --peel-tag
2023-11-02 16:53:24 +09:00
2fdfd7594f Merge branch 'rs/grep-parseopt-simplify' into maint-2.42
Simplify use of parse-options API a bit.

* rs/grep-parseopt-simplify:
  grep: use OPT_INTEGER_F for --max-depth
2023-11-02 16:53:24 +09:00
18e0648b9b Merge branch 'ob/sequencer-reword-error-message' into maint-2.42
Update an error message (which would probably never been seen).

* ob/sequencer-reword-error-message:
  sequencer: fix error message on failure to copy SQUASH_MSG
2023-11-02 16:53:23 +09:00
535b30eb58 Merge branch 'bc/more-git-var' into maint-2.42
Fix-up for a topic that already has graduated.

* bc/more-git-var:
  var: avoid a segmentation fault when `HOME` is unset
2023-11-02 16:53:23 +09:00
0510d06b56 Merge branch 'jk/ci-retire-allow-ref' into maint-2.42
CI update.

* jk/ci-retire-allow-ref:
  ci: deprecate ci/config/allow-ref script
  ci: allow branch selection through "vars"
2023-11-02 16:53:23 +09:00
1a3712f06b Merge branch 'ws/git-svn-retire-faketerm' into maint-2.42
Code clean-up.

* ws/git-svn-retire-faketerm:
  git-svn: drop FakeTerm hack
2023-11-02 16:53:22 +09:00
43af21409e Merge branch 'ch/t6300-verify-commit-test-cleanup' into maint-2.42
Test clean-up.

* ch/t6300-verify-commit-test-cleanup:
  t/t6300: drop magic filtering
  t/lib-gpg: forcibly run a trustdb update
2023-11-02 16:53:22 +09:00
7c7f6d828b Merge branch 'jc/mv-d-to-d-error-message-fix' into maint-2.42
Typofix in an error message.

* jc/mv-d-to-d-error-message-fix:
  mv: fix error for moving directory to another
2023-11-02 16:53:22 +09:00
9d4a69f852 Merge branch 'ja/worktree-orphan' into maint-2.42
Typofix in an error message.

* ja/worktree-orphan:
  builtin/worktree.c: fix typo in "forgot fetch" msg
2023-11-02 16:53:21 +09:00
8db7d2d6bd Merge branch 'ob/t9001-indent-fix' into maint-2.42
Test style fix.

* ob/t9001-indent-fix:
  t9001: fix indentation in test_no_confirm()
2023-11-02 16:53:21 +09:00
b50a670153 Merge branch 'jk/function-pointer-mismatches-fix' into maint-2.42
Code clean-up to please clang-18.

* jk/function-pointer-mismatches-fix:
  hashmap: use expected signatures for comparison functions
2023-11-02 16:53:21 +09:00
9ae84d2e7f Merge branch 'ds/upload-pack-error-sequence-fix' into maint-2.42
Error message generation fix.

* ds/upload-pack-error-sequence-fix:
  upload-pack: fix exit code when denying fetch of unreachable object ID
  upload-pack: fix race condition in error messages
2023-11-02 16:53:20 +09:00
c78718c4b3 Merge branch 'ws/git-push-doc-grammofix' into maint-2.42
Doc update.

* ws/git-push-doc-grammofix:
  git-push.txt: fix grammar
2023-11-02 16:53:20 +09:00
07011e1480 Merge branch 'jk/test-pass-ubsan-options-to-http-test' into maint-2.42
UBSAN options were not propagated through the test framework to git
run via the httpd, unlike ASAN options, which has been corrected.

* jk/test-pass-ubsan-options-to-http-test:
  test-lib: set UBSAN_OPTIONS to match ASan
2023-11-02 16:53:20 +09:00
584cde766b Merge branch 'tb/send-email-extract-valid-address-error-message-fix' into maint-2.42
An error message given by "git send-email" when given a malformed
address did not give correct information, which has been corrected.

* tb/send-email-extract-valid-address-error-message-fix:
  git-send-email.perl: avoid printing undef when validating addresses
2023-11-02 16:53:20 +09:00
2a6806140e Merge branch 'jk/redact-h2h3-headers-fix' into maint-2.42
HTTP Header redaction code has been adjusted for a newer version of
cURL library that shows its traces differently from earlier
versions.

* jk/redact-h2h3-headers-fix:
  http: update curl http/2 info matching for curl 8.3.0
  http: factor out matching of curl http/2 trace lines
2023-11-02 16:53:19 +09:00
83442ded89 Merge branch 'pb/completion-aliases-doc' into maint-2.42
Clarify how "alias.foo = : git cmd ; aliased-command-string" should
be spelled with necessary whitespaces around punctuation marks to
work.

* pb/completion-aliases-doc:
  completion: improve doc for complex aliases
2023-11-02 16:53:19 +09:00
2fd4378d64 Merge branch 'js/diff-cached-fsmonitor-fix' into maint-2.42
"git diff --cached" codepath did not fill the necessary stat
information for a file when fsmonitor knows it is clean and ended
up behaving as if it is not clean, which has been corrected.

* js/diff-cached-fsmonitor-fix:
  diff-lib: fix check_removed when fsmonitor is on
2023-11-02 16:53:19 +09:00
56ee4a3578 Merge branch 'js/systemd-timers-wsl-fix' into maint-2.42
Update "git maintainance" timers' implementation based on systemd
timers to work with WSL.

* js/systemd-timers-wsl-fix:
  maintenance(systemd): support the Windows Subsystem for Linux
2023-11-02 16:53:18 +09:00
bfb8376d68 Merge branch 'pw/diff-no-index-from-named-pipes' into maint-2.42
"git diff --no-index -R <(one) <(two)" did not work correctly,
which has been corrected.

* pw/diff-no-index-from-named-pipes:
  diff --no-index: fix -R with stdin
2023-11-02 16:53:18 +09:00
d12df942ba Merge branch 'js/complete-checkout-t' into maint-2.42
The completion script (in contrib/) has been taught to treat the
"-t" option to "git checkout" and "git switch" just like the
"--track" option, to complete remote-tracking branches.

* js/complete-checkout-t:
  completion(switch/checkout): treat --track and -t the same
2023-11-02 16:53:18 +09:00
17ab51ee8f Merge branch 'rs/grep-no-no-or' into maint-2.42
"git grep -e A --no-or -e B" is accepted, even though the negation
of "or" did not mean anything, which has been tightened.

* rs/grep-no-no-or:
  grep: reject --no-or
2023-11-02 16:53:18 +09:00
9a4ae43f0b Merge branch 'so/diff-doc-for-patch-update' into maint-2.42
References from description of the `--patch` option in various
manual pages have been simplified and improved.

* so/diff-doc-for-patch-update:
  doc/diff-options: fix link to generating patch section
2023-11-02 16:53:17 +09:00
a70f725c06 Merge branch 'pw/rebase-i-after-failure' into maint-2.42
Various fixes to the behaviour of "rebase -i" when the command got
interrupted by conflicting changes.
cf. <6b927687-cf6e-d73e-78fb-bd4f46736928@gmx.de>

* pw/rebase-i-after-failure:
  rebase -i: fix adding failed command to the todo list
  rebase --continue: refuse to commit after failed command
  rebase: fix rewritten list for failed pick
  sequencer: factor out part of pick_commits()
  sequencer: use rebase_path_message()
  rebase -i: remove patch file after conflict resolution
  rebase -i: move unlink() calls
2023-11-02 16:53:17 +09:00
d97034b0a1 Merge branch 'ks/ref-filter-sort-numerically' into maint-2.42
"git for-each-ref --sort='contents:size'" sorts the refs according
to size numerically, giving a ref that points at a blob twelve-byte
(12) long before showing a blob hundred-byte (100) long.

* ks/ref-filter-sort-numerically:
  ref-filter: sort numerically when ":size" is used
2023-11-02 16:53:17 +09:00
57b52cec46 Merge branch 'jk/diff-result-code-cleanup' into maint-2.42
"git diff --no-such-option" and other corner cases around the exit
status of the "diff" command has been corrected.

* jk/diff-result-code-cleanup:
  diff: drop useless "status" parameter from diff_result_code()
  diff: drop useless return values in git-diff helpers
  diff: drop useless return from run_diff_{files,index} functions
  diff: die when failing to read index in git-diff builtin
  diff: show usage for unknown builtin_diff_files() options
  diff-files: avoid negative exit value
  diff: spell DIFF_INDEX_CACHED out when calling run_diff_index()
2023-11-02 16:53:16 +09:00
a00b1127ce Merge branch 'ob/sequencer-empty-hint-fix' into maint-2.42
The use of API between two calls to require_clean_work_tree() from
the sequencer code has been cleaned up for consistency.

* ob/sequencer-empty-hint-fix:
  sequencer: rectify empty hint in call of require_clean_work_tree()
2023-11-02 16:53:16 +09:00
7f8314f277 Merge branch 'ts/unpacklimit-config-fix' into maint-2.42
transfer.unpackLimit ought to be used as a fallback, but overrode
fetch.unpackLimit and receive.unpackLimit instead.

* ts/unpacklimit-config-fix:
  transfer.unpackLimit: fetch/receive.unpackLimit takes precedence
2023-11-02 16:53:16 +09:00
8764491463 Merge branch 'jc/diff-exit-code-with-w-fixes' into maint-2.42
"git diff -w --exit-code" with various options did not work
correctly, which is being addressed.

* jc/diff-exit-code-with-w-fixes:
  diff: the -w option breaks --exit-code for --raw and other output modes
  t4040: remove test that succeeded for a wrong reason
  diff: teach "--stat -w --exit-code" to notice differences
  diff: mode-only change should be noticed by "--patch -w --exit-code"
  diff: move the fallback "--exit-code" code down
2023-11-02 16:53:15 +09:00
1ea39ad467 Merge branch 'tb/commit-graph-verify-fix' into maint-2.42
The commit-graph verification code that detects mixture of zero and
non-zero generation numbers has been updated.

* tb/commit-graph-verify-fix:
  commit-graph: avoid repeated mixed generation number warnings
  t/t5318-commit-graph.sh: test generation zero transitions during fsck
  commit-graph: verify swapped zero/non-zero generation cases
  commit-graph: introduce `commit_graph_generation_from_graph()`
2023-11-02 16:53:15 +09:00
ec7cc187d4 Merge branch 'jc/ci-skip-same-commit' into maint-2.42
Tweak GitHub Actions CI so that pushing the same commit to multiple
branch tips at the same time will not waste building and testing
the same thing twice.

* jc/ci-skip-same-commit:
  ci: avoid building from the same commit in parallel
2023-11-02 16:53:15 +09:00
50758312f2 Merge branch 'ds/scalar-updates' into maint-2.42
Scalar updates.

* ds/scalar-updates:
  scalar reconfigure: help users remove buggy repos
  setup: add discover_git_directory_reason()
  scalar: add --[no-]src option
2023-11-02 16:53:15 +09:00
396a167bd4 Merge branch 'mp/rebase-label-length-limit' into maint-2.42
Overly long label names used in the sequencer machinery are now
chopped to fit under filesystem limitation.

* mp/rebase-label-length-limit:
  rebase: allow overriding the maximal length of the generated labels
  sequencer: truncate labels to accommodate loose refs
2023-11-02 16:53:14 +09:00
31730a30a0 Merge branch 'js/ci-coverity' into maint-2.42
GitHub CI workflow has learned to trigger Coverity check.

* js/ci-coverity:
  coverity: detect and report when the token or project is incorrect
  coverity: allow running on macOS
  coverity: support building on Windows
  coverity: allow overriding the Coverity project
  coverity: cache the Coverity Build Tool
  ci: add a GitHub workflow to submit Coverity scans
2023-11-02 16:53:14 +09:00
6d68ab0819 Merge branch 'jk/test-lsan-denoise-output' into maint-2.42
Tests with LSan from time to time seem to emit harmless message
that makes our tests unnecessarily flakey; we work it around by
filtering the uninteresting output.

* jk/test-lsan-denoise-output:
  test-lib: ignore uninteresting LSan output
2023-11-02 16:53:14 +09:00
19ab8e8dd5 Merge branch 'js/ci-san-skip-p4-and-svn-tests' into maint-2.42
Flakey "git p4" tests, as well as "git svn" tests, are now skipped
in the (rather expensive) sanitizer CI job.

* js/ci-san-skip-p4-and-svn-tests:
  ci(linux-asan-ubsan): let's save some time
2023-11-02 16:53:13 +09:00
fc0269be63 Merge branch 'tb/mark-more-tests-as-leak-free' into maint-2.42
Tests that are known to pass with LSan are now marked as such.

* tb/mark-more-tests-as-leak-free:
  leak tests: mark t5583-push-branches.sh as leak-free
  leak tests: mark t3321-notes-stripspace.sh as leak-free
  leak tests: mark a handful of tests as leak-free
2023-11-02 16:53:13 +09:00
b64d78ad02 max_tree_depth: lower it for MSVC to avoid stack overflows
There seems to be some internal stack overflow detection in MSVC's
`malloc()` machinery that seems to be independent of the `stack reserve`
and `heap reserve` sizes specified in the executable (editable via
`EDITBIN /STACK:<n> <exe>` and `EDITBIN /HEAP:<n> <exe>`).

In the newly test cases added by `jk/tree-name-and-depth-limit`, this
stack overflow detection is unfortunately triggered before Git can print
out the error message about too-deep trees and exit gracefully. Instead,
it exits with `STATUS_STACK_OVERFLOW`. This corresponds to the numeric
value -1073741571, something the MSYS2 runtime we sadly need to use to
run Git's test suite cannot handle and which it internally maps to the
exit code 127. Git's test suite, in turn, mistakes this to mean that the
command was not found, and fails both test cases.

Here is an example stack trace from an example run:

    [0x0]   ntdll!RtlpAllocateHeap+0x31   0x4212603f50   0x7ff9d6d4cd49
    [0x1]   ntdll!RtlpAllocateHeapInternal+0x6c9   0x42126041b0   0x7ff9d6e14512
    [0x2]   ntdll!RtlDebugAllocateHeap+0x102   0x42126042b0   0x7ff9d6dcd8b0
    [0x3]   ntdll!RtlpAllocateHeap+0x7ec70   0x4212604350   0x7ff9d6d4cd49
    [0x4]   ntdll!RtlpAllocateHeapInternal+0x6c9   0x42126045b0   0x7ff9596ed480
    [0x5]   ucrtbased!heap_alloc_dbg_internal+0x210   0x42126046b0   0x7ff9596ed20d
    [0x6]   ucrtbased!heap_alloc_dbg+0x4d   0x4212604750   0x7ff9596f037f
    [0x7]   ucrtbased!_malloc_dbg+0x2f   0x42126047a0   0x7ff9596f0dee
    [0x8]   ucrtbased!malloc+0x1e   0x42126047d0   0x7ff730fcc1ef
    [0x9]   git!do_xmalloc+0x2f   0x4212604800   0x7ff730fcc2b9
    [0xa]   git!do_xmallocz+0x59   0x4212604840   0x7ff730fca779
    [0xb]   git!xmallocz_gently+0x19   0x4212604880   0x7ff7311b0883
    [0xc]   git!unpack_compressed_entry+0x43   0x42126048b0   0x7ff7311ac9a4
    [0xd]   git!unpack_entry+0x554   0x42126049a0   0x7ff7311b0628
    [0xe]   git!cache_or_unpack_entry+0x58   0x4212605250   0x7ff7311ad3a8
    [0xf]   git!packed_object_info+0x98   0x42126052a0   0x7ff7310a92da
    [0x10]   git!do_oid_object_info_extended+0x3fa   0x42126053b0   0x7ff7310a44e7
    [0x11]   git!oid_object_info_extended+0x37   0x4212605460   0x7ff7310a38ba
    [0x12]   git!repo_read_object_file+0x9a   0x42126054a0   0x7ff7310a6147
    [0x13]   git!read_object_with_reference+0x97   0x4212605560   0x7ff7310b4656
    [0x14]   git!fill_tree_descriptor+0x66   0x4212605620   0x7ff7310dc0a5
    [0x15]   git!traverse_trees_recursive+0x3f5   0x4212605680   0x7ff7310dd831
    [0x16]   git!unpack_callback+0x441   0x4212605790   0x7ff7310b4c95
    [0x17]   git!traverse_trees+0x5d5   0x42126058a0   0x7ff7310dc0f2
    [0x18]   git!traverse_trees_recursive+0x442   0x4212605980   0x7ff7310dd831
    [0x19]   git!unpack_callback+0x441   0x4212605a90   0x7ff7310b4c95
    [0x1a]   git!traverse_trees+0x5d5   0x4212605ba0   0x7ff7310dc0f2
    [0x1b]   git!traverse_trees_recursive+0x442   0x4212605c80   0x7ff7310dd831
    [0x1c]   git!unpack_callback+0x441   0x4212605d90   0x7ff7310b4c95
    [0x1d]   git!traverse_trees+0x5d5   0x4212605ea0   0x7ff7310dc0f2
    [0x1e]   git!traverse_trees_recursive+0x442   0x4212605f80   0x7ff7310dd831
    [0x1f]   git!unpack_callback+0x441   0x4212606090   0x7ff7310b4c95
    [0x20]   git!traverse_trees+0x5d5   0x42126061a0   0x7ff7310dc0f2
    [0x21]   git!traverse_trees_recursive+0x442   0x4212606280   0x7ff7310dd831
    [...]
    [0xfad]   git!cmd_main+0x2a2   0x42126ff740   0x7ff730fb6345
    [0xfae]   git!main+0xe5   0x42126ff7c0   0x7ff730fbff93
    [0xfaf]   git!wmain+0x2a3   0x42126ff830   0x7ff731318859
    [0xfb0]   git!invoke_main+0x39   0x42126ff8a0   0x7ff7313186fe
    [0xfb1]   git!__scrt_common_main_seh+0x12e   0x42126ff8f0   0x7ff7313185be
    [0xfb2]   git!__scrt_common_main+0xe   0x42126ff960   0x7ff7313188ee
    [0xfb3]   git!wmainCRTStartup+0xe   0x42126ff990   0x7ff9d5ed257d
    [0xfb4]   KERNEL32!BaseThreadInitThunk+0x1d   0x42126ff9c0   0x7ff9d6d6aa78
    [0xfb5]   ntdll!RtlUserThreadStart+0x28   0x42126ff9f0   0x0

I verified manually that `traverse_trees_cur_depth` was 562 when that
happened, which is far below the 2048 that were already accepted into
Git as a hard limit.

Despite many attempts to figure out which of the internals trigger this
`STATUS_STACK_OVERFLOW` and how to maybe increase certain sizes to avoid
running into this issue and let Git behave the same way as under Linux,
I failed to find any build-time/runtime knob we could turn to that
effect.

Note: even switching to using a different allocator (I used mimalloc
because that's what Git for Windows uses for its GCC builds) does not
help, as the zlib code used to unpack compressed pack entries _still_
uses the regular `malloc()`. And runs into the same issue.

Note also: switching to using a different allocator _also_ for zlib code
seems _also_ not to help. I tried that, and it still exited with
`STATUS_STACK_OVERFLOW` that seems to have been triggered by a
`mi_assert_internal()`, i.e. an internal assertion of mimalloc...

So the best bet to work around this for now seems to just lower the
maximum allowed tree depth _even further_ for MSVC builds.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-02 08:58:28 +09:00
e1068f0ad4 merge-file: add an option to process object IDs
git merge-file knows how to merge files on the file system already.  It
would be helpful, however, to allow it to also merge single blobs.
Teach it an `--object-id` option which means that its arguments are
object IDs and not files to allow it to do so.

We handle the empty blob specially since read_mmblob doesn't read it
directly and otherwise users cannot specify an empty ancestor.

Signed-off-by: brian m. carlson <bk2204@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-02 08:51:40 +09:00
8077612ea1 git-merge-file doc: drop "-file" from argument placeholders
`git merge-file` takes three positional arguments. Each of them is
documented as `<foo-file>`. In preparation for teaching this command to
alternatively take three object IDs, make these placeholders a bit more
generic by dropping the "-file" parts. Instead, clarify early that the
three arguments are filenames. Even after the next commit, we can afford
to present this file-centric view up front and in the general
discussion, since it will remain the default one.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: brian m. carlson <bk2204@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-02 08:51:38 +09:00
1bd809938a Documentation/gitformat-pack.txt: fix incorrect MIDX documentation
Back in 32f3c541e3 (multi-pack-index: write pack names in chunk,
2018-07-12) the MIDX's "Packfile Names" (or "PNAM", for short) chunk was
described as containing an array of string entries. e0d1bcf825 notes
that this is the only chunk in the MIDX format's specification that is
not guaranteed to be 4-byte aligned, and so should be placed last.

This isn't quite accurate: the entries within the PNAM chunk are not
guaranteed to be 4-byte aligned since they are arbitrary strings, but
the chunk itself is 4-byte aligned since the ending is padded with NUL
bytes.

That padding has always been there since 32f3c541e3 via
midx.c::write_midx_pack_names(), which ended with:

    i = MIDX_CHUNK_ALIGNMENT - (written % MIDX_CHUNK_ALIGNMENT)
    if (i < MIDX_CHUNK_ALIGNMENT) {
      unsigned char padding[MIDX_CHUNK_ALIGNMENT];
      memset(padding, 0, sizeof(padding))
      hashwrite(f, padding, i);
      written += i;
    }

In fact, 32f3c541e3's log message itself describes the chunk in its
first paragraph with:

    Since filenames are not well structured, add padding to keep good
    alignment in later chunks.

So these have always been externally aligned. Correct the corresponding
part of our documentation to reflect that.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-01 13:25:04 +09:00
530a9f183f Documentation/gitformat-pack.txt: fix typo
e0d1bcf825 (multi-pack-index: add format details, 2018-07-12) describes
the MIDX's "PNAM" chunk as having entries which are "null-terminated
strings".

This is a typo, as strings are terminated with a NUL character, which is
a distinct concept from "NULL" or "null", which we typically reserve for
the void pointer to address 0.

Correct the documentation accordingly.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-01 13:25:02 +09:00
8f81532599 clang-format: fix typo in comment
Signed-off-by: Aditya Neelamraju <adityanv97@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-01 12:24:19 +09:00
0497e6c611 t: use git-show-ref(1) to check for ref existence
Convert tests that use `test_path_is_file` and `test_path_is_missing` to
instead use a set of helpers `test_ref_exists` and `test_ref_missing`.
These helpers are implemented via the newly introduced `git show-ref
--exists` command. Thus, we can avoid intimate knowledge of how the ref
backend stores references on disk.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-01 12:09:01 +09:00
9080a7f178 builtin/show-ref: add new mode to check for reference existence
While we have multiple ways to show the value of a given reference, we
do not have any way to check whether a reference exists at all. While
commands like git-rev-parse(1) or git-show-ref(1) can be used to check
for reference existence in case the reference resolves to something
sane, neither of them can be used to check for existence in some other
scenarios where the reference does not resolve cleanly:

    - References which have an invalid name cannot be resolved.

    - References to nonexistent objects cannot be resolved.

    - Dangling symrefs can be resolved via git-symbolic-ref(1), but this
      requires the caller to special case existence checks depending on
      whether or not a reference is symbolic or direct.

Furthermore, git-rev-list(1) and other commands do not let the caller
distinguish easily between an actually missing reference and a generic
error.

Taken together, this seems like sufficient motivation to introduce a
separate plumbing command to explicitly check for the existence of a
reference without trying to resolve its contents.

This new command comes in the form of `git show-ref --exists`. This
new mode will exit successfully when the reference exists, with a
specific exit code of 2 when it does not exist, or with 1 when there
has been a generic error.

Note that the only way to properly implement this command is by using
the internal `refs_read_raw_ref()` function. While the public function
`refs_resolve_ref_unsafe()` can be made to behave in the same way by
passing various flags, it does not provide any way to obtain the errno
with which the reference backend failed when reading the reference. As
such, it becomes impossible for us to distinguish generic errors from
the explicit case where the reference wasn't found.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-01 12:09:01 +09:00