diff options
| -rw-r--r-- | Documentation/git-merge-base.txt | 19 | ||||
| -rw-r--r-- | builtin/merge-base.c | 35 | ||||
| -rwxr-xr-x | t/t6010-merge-base.sh | 2 |
3 files changed, 46 insertions, 10 deletions
diff --git a/Documentation/git-merge-base.txt b/Documentation/git-merge-base.txt index 09b34b0501..125207ef1e 100644 --- a/Documentation/git-merge-base.txt +++ b/Documentation/git-merge-base.txt @@ -8,7 +8,7 @@ git-merge-base - Find as good common ancestors as possible for a merge SYNOPSIS -------- -'git merge-base' [-a|--all] <commit> <commit>... +'git merge-base' [-a|--all] [--octopus] <commit> <commit>... DESCRIPTION ----------- @@ -20,12 +20,12 @@ that does not have any better common ancestor is a 'best common ancestor', i.e. a 'merge base'. Note that there can be more than one merge base for a pair of commits. -Among the two commits to compute the merge base from, one is specified by -the first commit argument on the command line; the other commit is a -(possibly hypothetical) commit that is a merge across all the remaining -commits on the command line. As the most common special case, specifying only -two commits on the command line means computing the merge base between -the given two commits. +Unless `--octopus` is given, among the two commits to compute the merge +base from, one is specified by the first commit argument on the command +line; the other commit is a (possibly hypothetical) commit that is a merge +across all the remaining commits on the command line. As the most common +special case, specifying only two commits on the command line means +computing the merge base between the given two commits. As a consequence, the 'merge base' is not necessarily contained in each of the commit arguments if more than two commits are specified. This is different @@ -37,6 +37,11 @@ OPTIONS --all:: Output all merge bases for the commits, instead of just one. +--octopus:: + Compute the best common ancestors of all supplied commits, + in preparation for an n-way merge. This mimics the behavior + of 'git show-branch --merge-base'. + DISCUSSION ---------- diff --git a/builtin/merge-base.c b/builtin/merge-base.c index 54e7ec2237..c30128659f 100644 --- a/builtin/merge-base.c +++ b/builtin/merge-base.c @@ -23,7 +23,7 @@ static int show_merge_base(struct commit **rev, int rev_nr, int show_all) } static const char * const merge_base_usage[] = { - "git merge-base [-a|--all] <commit> <commit>...", + "git merge-base [-a|--all] [--octopus] <commit> <commit>...", NULL }; @@ -41,21 +41,50 @@ static struct commit *get_commit_reference(const char *arg) return r; } +static int show_octopus_merge_bases(int count, const char **args, int show_all) +{ + struct commit_list *revs = NULL; + struct commit_list *result; + int i; + + for (i = count - 1; i >= 0; i++) + commit_list_insert(get_commit_reference(args[i]), &revs); + result = get_octopus_merge_bases(revs); + + if (!result) + return 1; + + while (result) { + printf("%s\n", sha1_to_hex(result->item->object.sha1)); + if (!show_all) + return 0; + result = result->next; + } + + return 0; +} + int cmd_merge_base(int argc, const char **argv, const char *prefix) { struct commit **rev; int rev_nr = 0; int show_all = 0; + int octopus = 0; struct option options[] = { - OPT_BOOLEAN('a', "all", &show_all, "outputs all common ancestors"), + OPT_BOOLEAN('a', "all", &show_all, "output all common ancestors"), + OPT_BOOLEAN(0, "octopus", &octopus, "find ancestors for a single n-way merge"), OPT_END() }; git_config(git_default_config, NULL); argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0); - if (argc < 2) + if (!octopus && argc < 2) usage_with_options(merge_base_usage, options); + + if (octopus) + return show_octopus_merge_bases(argc, argv, show_all); + rev = xmalloc(argc * sizeof(*rev)); while (argc-- > 0) rev[rev_nr++] = get_commit_reference(*argv++); diff --git a/t/t6010-merge-base.sh b/t/t6010-merge-base.sh index 4466e45790..001431b363 100755 --- a/t/t6010-merge-base.sh +++ b/t/t6010-merge-base.sh @@ -164,9 +164,11 @@ test_expect_success 'merge-base A B C' ' git rev-parse --verify MMR >expected.sb && git merge-base --all MMA MMB MMC >actual && + git merge-base --all --octopus MMA MMB MMC >actual.common && git show-branch --merge-base MMA MMB MMC >actual.sb && test_cmp expected actual && + test_cmp expected.sb actual.common && test_cmp expected.sb actual.sb ' |