From a1e0ad78b784fd7c47c7bc2847f4813aca4cebaf Mon Sep 17 00:00:00 2001 From: Jonathan Nieder Date: Tue, 17 Aug 2010 02:01:54 -0500 Subject: [PATCH] merge-base --independent to print reduced parent list in a merge While show-branch --independent does not support more than MAX_REVS revs, git internally supports more with a different algorithm. Expose that functionality as "git merge-base --independent". This should help scripts to catch up with builtin merge in supporting dodecapus. Signed-off-by: Jonathan Nieder Signed-off-by: Junio C Hamano --- Documentation/git-merge-base.txt | 9 ++++++++ builtin/merge-base.c | 21 ++++++++++++----- t/t6010-merge-base.sh | 39 +++++++++++++++++++++++++++++++- 3 files changed, 62 insertions(+), 7 deletions(-) diff --git a/Documentation/git-merge-base.txt b/Documentation/git-merge-base.txt index 125207ef1..eedef1bb1 100644 --- a/Documentation/git-merge-base.txt +++ b/Documentation/git-merge-base.txt @@ -8,7 +8,9 @@ git-merge-base - Find as good common ancestors as possible for a merge SYNOPSIS -------- +[verse] 'git merge-base' [-a|--all] [--octopus] ... +'git merge-base' --independent ... DESCRIPTION ----------- @@ -42,6 +44,13 @@ OPTIONS in preparation for an n-way merge. This mimics the behavior of 'git show-branch --merge-base'. +--independent:: + Instead of printing merge bases, print a minimal subset of + the supplied commits with the same ancestors. In other words, + among the commits given, list those which cannot be reached + from any other. This mimics the behavior of 'git show-branch + --independent'. + DISCUSSION ---------- diff --git a/builtin/merge-base.c b/builtin/merge-base.c index c30128659..96dd16073 100644 --- a/builtin/merge-base.c +++ b/builtin/merge-base.c @@ -24,6 +24,7 @@ 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] [--octopus] ...", + "git merge-base --independent ...", NULL }; @@ -41,15 +42,19 @@ 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) +static int handle_octopus(int count, const char **args, int reduce, int show_all) { struct commit_list *revs = NULL; struct commit_list *result; int i; - for (i = count - 1; i >= 0; i++) + if (reduce) + show_all = 1; + + for (i = count - 1; i >= 0; i--) commit_list_insert(get_commit_reference(args[i]), &revs); - result = get_octopus_merge_bases(revs); + + result = reduce ? reduce_heads(revs) : get_octopus_merge_bases(revs); if (!result) return 1; @@ -70,20 +75,24 @@ int cmd_merge_base(int argc, const char **argv, const char *prefix) int rev_nr = 0; int show_all = 0; int octopus = 0; + int reduce = 0; struct option options[] = { OPT_BOOLEAN('a', "all", &show_all, "output all common ancestors"), OPT_BOOLEAN(0, "octopus", &octopus, "find ancestors for a single n-way merge"), + OPT_BOOLEAN(0, "independent", &reduce, "list revs not reachable from others"), OPT_END() }; git_config(git_default_config, NULL); argc = parse_options(argc, argv, prefix, options, merge_base_usage, 0); - if (!octopus && argc < 2) + if (!octopus && !reduce && argc < 2) usage_with_options(merge_base_usage, options); + if (reduce && (show_all || octopus)) + die("--independent cannot be used with other options"); - if (octopus) - return show_octopus_merge_bases(argc, argv, show_all); + if (octopus || reduce) + return handle_octopus(argc, argv, reduce, show_all); rev = xmalloc(argc * sizeof(*rev)); while (argc-- > 0) diff --git a/t/t6010-merge-base.sh b/t/t6010-merge-base.sh index 001431b36..62197a3d3 100755 --- a/t/t6010-merge-base.sh +++ b/t/t6010-merge-base.sh @@ -3,7 +3,7 @@ # Copyright (c) 2005 Junio C Hamano # -test_description='Merge base computation. +test_description='Merge base and parent list computation. ' . ./test-lib.sh @@ -75,6 +75,26 @@ test_expect_success 'merge-base G H' ' test_cmp expected actual.sb ' +test_expect_success 'merge-base/show-branch --independent' ' + git name-rev "$H" >expected1 && + git name-rev "$H" "$G" >expected2 && + + parents=$(git merge-base --independent H) && + git name-rev $parents >actual1.mb && + parents=$(git merge-base --independent A H G) && + git name-rev $parents >actual2.mb && + + parents=$(git show-branch --independent H) && + git name-rev $parents >actual1.sb && + parents=$(git show-branch --independent A H G) && + git name-rev $parents >actual2.sb && + + test_cmp expected1 actual1.mb && + test_cmp expected2 actual2.mb && + test_cmp expected1 actual1.sb && + test_cmp expected2 actual2.sb +' + test_expect_success 'unsynchronized clocks' ' # This test is to demonstrate that relying on timestamps in a distributed # SCM to provide a _consistent_ partial ordering of commits leads to @@ -125,6 +145,23 @@ test_expect_success 'unsynchronized clocks' ' test_cmp expected actual.all ' +test_expect_success '--independent with unsynchronized clocks' ' + IB=$(doit 0 IB) && + I1=$(doit -10 I1 $IB) && + I2=$(doit -9 I2 $I1) && + I3=$(doit -8 I3 $I2) && + I4=$(doit -7 I4 $I3) && + I5=$(doit -6 I5 $I4) && + I6=$(doit -5 I6 $I5) && + I7=$(doit -4 I7 $I6) && + I8=$(doit -3 I8 $I7) && + IH=$(doit -2 IH $I8) && + + echo $IH >expected && + git merge-base --independent IB IH >actual && + test_cmp expected actual +' + test_expect_success 'merge-base for octopus-step (setup)' ' # Another set to demonstrate base between one commit and a merge # in the documentation. -- 2.30.2