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2025-07-14Merge branch 'ps/perlless-test-fixes'Junio C Hamano1-2/+2
Test fixes. * ps/perlless-test-fixes: t5333: fix missing terminator for sed(1) 's' command t4150: fix warning printed by awk due to escaped '\@'
2025-07-07t5333: fix missing terminator for sed(1) 's' commandPatrick Steinhardt1-2/+2
In 6aec8d38fdd (t: refactor tests depending on Perl to print data, 2025-04-03) we have changed some of the tests in t4150 to use sed(1) instead of Perl. One of the conversions is broken though: sed: -e expression #1, char 41: unterminated `s' command Curiously enough, the test itself still passes. This is caused by a sequence of failures: 1. The output of sed(1) is piped into git-update-ref(1), and because sed(1) is the upstream command we don't notice that it fails. 2. git-update-ref(1) does not receive any input and thus won't create any references. 3. We then repack the repository with the configured pseudo merges pattern, but as we didn't create any references the pattern doesn't match anything. 4. We use `test_pseudo_merges()` to compute the list of pseudo-merges and write it into a file. This file is empty as there are none. 5. The loop over the pseudo-merges becomes a no-op. 6. The final test succeeds as well because the number of lines in an empty file is obviously the same as the number of unique lines, namely zero. Fix the issue by adding the terminating '|' to the sed(1) command. Furthermore, make the test a tiny bit more robust by not using it as part of a pipe. Reported-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-06-09pack-bitmap: remove checks before bitmap_freeLidong Yan1-0/+17
In pack-bitmap.c:find_boundary_objects(), the roots_bitmap is only freed if cascade_pseudo_merges_1() fails. However, cascade_pseudo_merges_1() uses roots_bitmap as a mutable reference without taking ownership of it. As a result, if cascade_pseudo_merges_1() succeeds, roots_bitmap is leaked. And this leak currently lacks a dedicated test to detect it. To fix this leak, remove if cascade_pseudo_merges_1() succeed check and always calling bitmap_free(roots_bitmap); To trigger this leak, we need roots_bitmap that contains at least one pseudo merge. So that we can use pseudo merge bitmap when we compute roots reachable bitmap. Here we create two commits: first A then B. Add A to the pseudo-merge and perform a traversal over the range A..B. In this scenario, the "haves" set will be {A}, and cascade_pseudo_merges_1 will succeed, thereby exposing the leak due to the missing roots_bitmap cleanup. Signed-off-by: Lidong Yan <502024330056@smail.nju.edu.cn> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-04-07t: refactor tests depending on Perl to print dataPatrick Steinhardt1-13/+5
A bunch of tests rely on Perl to print data in various different ways. These usages fall into the following categories: - Print data conditionally by matching patterns. These usecases can be converted to use awk(1) rather easily. - Print data repeatedly. These usecases can typically be converted to use a combination of `test-tool genzeros` and sed(1). - Print data in reverse. These usecases can be converted to use awk(1) or `sort -r`. Refactor the tests accordingly so that we can drop a couple of PERL_TEST_HELPERS prerequisites. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-04-07t: introduce PERL_TEST_HELPERS prerequisitePatrick Steinhardt1-0/+6
In the early days of Git, Perl was used quite prominently throughout the project. This has changed significantly as almost all of the executables we ship nowadays have eventually been rewritten in C. Only a handful of subsystems remain that require Perl: - gitweb, a read-only web interface. - A couple of scripts that allow importing repositories from GNU Arch, CVS and Subversion. - git-send-email(1), which can be used to send mails. - git-request-pull(1), which is used to request somebody to pull from a URL by sending an email. - git-filter-branch(1), which uses Perl with the `--state-branch` option. This command is typically recommended against nowadays in favor of git-filter-repo(1). - Our Perl bindings for Git. - The netrc Git credential helper. None of these subsystems can really be considered to be part of the "core" of Git, and an installation without them is fully functional. It is more likely than not that an end user wouldn't even notice that any features are missing if those tools weren't installed. But while Perl nowadays very much is an optional dependency of Git, there is a significant limitation when Perl isn't available: developers cannot run our test suite. Preceding commits have started to lift this restriction by removing the strict dependency on Perl in many central parts of the test library. But there are still many tests that rely on small Perl helpers to do various different things. Introduce a new PERL_TEST_HELPERS prerequisite that guards all tests that require Perl. This prerequisite is explicitly different than the preexisting PERL prerequisite: - PERL records whether or not features depending on the Perl interpreter are built. - PERL_TEST_HELPERS records whether or not a Perl interpreter is available for our tests. By having these two separate prerequisites we can thus distinguish between tests that inherently depend on Perl because the underlying feature does, and those tests that depend on Perl because the test itself is using Perl. Adapt all tests to set the PERL_TEST_HELPERS prerequisite as needed. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-02-12Merge branch 'ds/name-hash-tweaks'Junio C Hamano1-1/+2
"git pack-objects" and its wrapper "git repack" learned an option to use an alternative path-hash function to improve delta-base selection to produce a packfile with deeper history than window size. * ds/name-hash-tweaks: pack-objects: prevent name hash version change test-tool: add helper for name-hash values p5313: add size comparison test pack-objects: add GIT_TEST_NAME_HASH_VERSION repack: add --name-hash-version option pack-objects: add --name-hash-version option pack-objects: create new name-hash function version
2025-01-27pack-objects: add GIT_TEST_NAME_HASH_VERSIONDerrick Stolee1-1/+2
Add a new environment variable to opt-in to different values of the --name-hash-version=<n> option in 'git pack-objects'. This allows for extra testing of the feature without repeating all of the test scenarios. Unlike many GIT_TEST_* variables, we are choosing to not add this to the linux-TEST-vars CI build as that test run is already overloaded. The behavior exposed by this test variable is of low risk and should be sufficient to allow manual testing when an issue arises. But this option isn't free. There are a few tests that change behavior with the variable enabled. First, there are a few tests that are very sensitive to certain delta bases being picked. These are both involving the generation of thin bundles and then counting their objects via 'git index-pack --fix-thin' which pulls the delta base into the new packfile. For these tests, disable the option as a decent long-term option. Second, there are some tests that compare the exact output of a 'git pack-objects' process when using bitmaps. The warning that ignores the --name-hash-version=2 and forces version 1 causes these tests to fail. Disable the environment variable to get around this issue. Signed-off-by: Derrick Stolee <stolee@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-11-21t: remove TEST_PASSES_SANITIZE_LEAK annotationsPatrick Steinhardt1-1/+0
Now that the default value for TEST_PASSES_SANITIZE_LEAK is `true` there is no longer a need to have that variable declared in all of our tests. Drop it. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-09-30pack-bitmap-write: fix leaking OID arrayPatrick Steinhardt1-0/+1
Fix a leaking OID array in `write_pseudo_merges()`. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15pseudo-merge.c: ensure pseudo-merge groups are closedTaylor Blau1-0/+36
When generating pseudo-merge bitmaps, it's possible that concurrent reference updates may reveal some pseudo-merge candidates which reach objects that are not contained in the bitmap's pack or pseudo-pack order (in the case of MIDX bitmaps). The latter case is relatively easy to demonstrate: if we generate a MIDX bitmap with only half of the repository packed, then the unpacked contents are not part of the MIDX's object order. If we happen to select one or more commit(s) from the unpacked portion of the repository for inclusion in a pseudo-merge, we'll get the following message when trying to generate its bitmap: $ git multi-pack-index write --bitmap [...] Selecting pseudo-merge commits: 100% (1/1), done. warning: Failed to write bitmap index. Packfile doesn't have full closure (object ... is missing) Building bitmaps: 50% (1/2), done. error: could not write multi-pack bitmap , and the attempted bitmap write will fail, leaving the repository without a current bitmap. Rectify this by ensuring that the commits which are pseudo-merge candidates can only be so if they appear somewhere in the packing order. This is sufficient, since we know that the original packing order is closed under reachability, so if a commit appears in that list as a potential pseudo-merge candidate, we know that everything reachable from it also appears in the list (and thus the candidate is a good one). Noticed-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15pseudo-merge.c: do not generate empty pseudo-merge commitsTaylor Blau1-1/+1
The previous commit demonstrated it is possible to generate empty pseudo-merge commits, which is not useful as such pseudo-merges carry no information. Ensure that we only generate non-empty groups by not pushing a new commit onto the bitmap_writer when that commit has no parents. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-08-15t/t5333-pseudo-merge-bitmaps.sh: demonstrate empty pseudo-merge groupsTaylor Blau1-0/+20
Demonstrate that it is possible to generate empty pseudo-merge commits in certain cases. In the below instance, we generate one non-empty pseudo-merge (containing commit "base"), and one empty pseudo-merge group (corresponding to the unstable commits within that group). (In my testing, the pseudo-merge machinery seems to handle empty groups just fine, but generating them is pointless as they carry no information.) This commit (introducing a deliberate "test_expect_failure") is split out from the actual fix (which will appear in the following commit) to demonstrate that the failure is correctly induced. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24pseudo-merge: implement support for finding existing mergesTaylor Blau1-0/+65
This patch implements support for reusing existing pseudo-merge commits when writing bitmaps when there is an existing pseudo-merge bitmap which has exactly the same set of parents as one that we are about to write. Note that unstable pseudo-merges are likely to change between consecutive repacks, and so are generally poor candidates for reuse. However, stable pseudo-merges (see the configuration option 'bitmapPseudoMerge.<name>.stableThreshold') are by definition unlikely to change between runs (as they represent long-running branches). Because there is no index from a *set* of pseudo-merge parents to a matching pseudo-merge bitmap, we have to construct the bitmap corresponding to the set of parents for each pending pseudo-merge commit and see if a matching bitmap exists. This is technically quadratic in the number of pseudo-merges, but is OK in practice for a couple of reasons: - non-matching pseudo-merge bitmaps are rejected quickly as soon as they differ in a single bit - already-matched pseudo-merge bitmaps are discarded from subsequent rounds of search - the number of pseudo-merges is generally small, even for large repositories In order to do this, implement (a) a function that finds a matching pseudo-merge given some uncompressed bitset describing its parents, (b) a function that computes the bitset of parents for a given pseudo-merge commit, and (c) call that function before computing the set of reachable objects for some pending pseudo-merge. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-05-24pack-bitmap.c: use pseudo-merges during traversalTaylor Blau1-0/+328
Now that all of the groundwork has been laid to support reading and using pseudo-merges, make use of that work in this commit by teaching the pack-bitmap machinery to use pseudo-merge(s) when available during traversal. The basic operation is as follows: - When enumerating objects on either side of a reachability query, first see if any subset of the roots satisfies some pseudo-merge bitmap. If it does, apply that pseudo-merge bitmap. - If any pseudo-merge bitmap(s) were applied in the previous step, OR them into the result[^1]. Then repeat the process over all pseudo-merge bitmaps (we'll refer to this as "cascading" pseudo-merges). Once this is done, OR in the resulting bitmap. - If there is no fill-in traversal to be done, return the bitmap for that side of the reachability query. If there is fill-in traversal, then for each commit we encounter via show_commit(), check to see if any unsatisfied pseudo-merges containing that commit as one of its parents has been made satisfied by the presence of that commit. If so, OR in the object set from that pseudo-merge bitmap, and then cascade. If not, continue traversal. A similar implementation is present in the boundary-based bitmap traversal routines. [^1]: Importantly, we cannot OR in the entire set of roots along with the objects reachable from whatever pseudo-merge bitmaps were satisfied. This may leave some dangling bits corresponding to any unsatisfied root(s) getting OR'd into the resulting bitmap, tricking other parts of the traversal into thinking we already have a reachability closure over those commit(s) when we do not. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>