@matheusbsbs / matheus-bagliano / commits / 207c40e1e4

commit-reach(repo_in_merge_bases_many): optionally expect missing commits

Currently this function treats unrelated commit histories the same way as commit histories with missing commit objects. Typically, missing commit objects constitute a corrupt repository, though, and should be reported as such. The next commits will make it so, but there is one exception: In `git fetch --update-shallow` we _expect_ commit objects to be missing, and we do want to treat the now-incomplete commit histories as unrelated. To allow for that, let's introduce an additional parameter that is passed to `repo_in_merge_bases_many()` to trigger this behavior, and use it in the two callers in `shallow.c`. This commit changes behavior slightly: unless called from the `shallow.c` functions that set the `ignore_missing_commits` bit, any non-existing tip commit that is passed to `repo_in_merge_bases_many()` will now result in an error. Note: When encountering missing commits while traversing the commit history in search for merge bases, with this commit there won't be a change in behavior just yet, their children will still be interpreted as root commits. This bug will get fixed by follow-up commits. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Johannes Schindelin committed Feb 28, 2024 at 09:44 UTC 207c40e1e43c992a8b268a3395ca104566612c6e

5 files changed +12 -9

commit-reach.c

+5 -4

@@ -466,7 +466,7 @@ int repo_is_descendant_of(struct repository *r,

466

467 other = with_commit->item;

468 with_commit = with_commit->next;

469 - if (repo_in_merge_bases_many(r, other, 1, &commit))

469 + if (repo_in_merge_bases_many(r, other, 1, &commit, 0))

470 return 1;

471 }

472 return 0;

@@ -477,17 +477,18 @@ int repo_is_descendant_of(struct repository *r,

477 * Is "commit" an ancestor of one of the "references"?

478 */

479 int repo_in_merge_bases_many(struct repository *r, struct commit *commit,

480 - int nr_reference, struct commit **reference)

480 + int nr_reference, struct commit **reference,

481 + int ignore_missing_commits)

482 {

483 struct commit_list *bases;

484 int ret = 0, i;

485 timestamp_t generation, max_generation = GENERATION_NUMBER_ZERO;

486

487 if (repo_parse_commit(r, commit))

487 - return ret;

488 + return ignore_missing_commits ? 0 : -1;

489 for (i = 0; i < nr_reference; i++) {

490 if (repo_parse_commit(r, reference[i]))

490 - return ret;

491 + return ignore_missing_commits ? 0 : -1;

492

493 generation = commit_graph_generation(reference[i]);

494 if (generation > max_generation)

commit-reach.h

+2 -1

@@ -30,7 +30,8 @@ int repo_in_merge_bases(struct repository *r,

30 struct commit *reference);

31 int repo_in_merge_bases_many(struct repository *r,

32 struct commit *commit,

33 - int nr_reference, struct commit **reference);

33 + int nr_reference, struct commit **reference,

34 + int ignore_missing_commits);

36 /*

37 * Takes a list of commits and returns a new list where those

remote.c

+1 -1

@@ -2680,7 +2680,7 @@ static int is_reachable_in_reflog(const char *local, const struct ref *remote)

2680 if (MERGE_BASES_BATCH_SIZE < size)

2681 size = MERGE_BASES_BATCH_SIZE;

2682

2683 - if ((ret = repo_in_merge_bases_many(the_repository, commit, size, chunk)))

2683 + if ((ret = repo_in_merge_bases_many(the_repository, commit, size, chunk, 0)))

2684 break;

2685 }

2686

shallow.c

+3 -2

@@ -796,7 +796,7 @@ static void post_assign_shallow(struct shallow_info *info,

796 for (j = 0; j < bitmap_nr; j++)

797 if (bitmap[0][j] &&

798 /* Step 7, reachability test at commit level */

799 - !repo_in_merge_bases_many(the_repository, c, ca.nr, ca.commits)) {

799 + !repo_in_merge_bases_many(the_repository, c, ca.nr, ca.commits, 1)) {

800 update_refstatus(ref_status, info->ref->nr, *bitmap);

801 dst++;

802 break;

@@ -827,7 +827,8 @@ int delayed_reachability_test(struct shallow_info *si, int c)

827 si->reachable[c] = repo_in_merge_bases_many(the_repository,

828 commit,

829 si->nr_commits,

830 - si->commits);

830 + si->commits,

831 + 1);

832 si->need_reachability_test[c] = 0;

833 }

834 return si->reachable[c];

t/helper/test-reach.c

+1 -1

@@ -111,7 +111,7 @@ int cmd__reach(int ac, const char **av)

111 repo_in_merge_bases(the_repository, A, B));

112 else if (!strcmp(av[1], "in_merge_bases_many"))

113 printf("%s(A,X):%d\n", av[1],

114 - repo_in_merge_bases_many(the_repository, A, X_nr, X_array));

114 + repo_in_merge_bases_many(the_repository, A, X_nr, X_array, 0));

115 else if (!strcmp(av[1], "is_descendant_of"))

116 printf("%s(A,X):%d\n", av[1], repo_is_descendant_of(r, A, X));

117 else if (!strcmp(av[1], "get_merge_bases_many")) {