From 4b7f53da7618e94985c9d9d5081b4bc44c45de2f Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Thu, 17 Jan 2013 14:23:03 -0800 Subject: [PATCH] simplify-merges: drop merge from irrelevant side branch The merge simplification rule stated in 6546b59 (revision traversal: show full history with merge simplification, 2008-07-31) still treated merge commits too specially. Namely, in a history with this shape: ---o---o---M / x---x---x where three 'x' were on a history completely unrelated to the main history 'o' and do not touch any of the paths we are following, we still said that after simplifying all of the parents of M, 'x' (which is the leftmost 'x' that rightmost 'x simplifies down to) and 'o' (which would be the last commit on the main history that touches the paths we are following) are independent from each other, and both need to be kept. That is incorrect; when the side branch 'x' never touches the paths, it should be removed to allow M to simplify down to the last commit on the main history that touches the paths. Signed-off-by: Junio C Hamano --- revision.c | 23 +++++++++++++++++++++++ t/t6012-rev-list-simplify.sh | 26 +++++++++++++++++++++----- 2 files changed, 44 insertions(+), 5 deletions(-) diff --git a/revision.c b/revision.c index 33cb207f28..3536635a88 100644 --- a/revision.c +++ b/revision.c @@ -1424,6 +1424,22 @@ static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, return st; } +static void remove_treesame_parents(struct commit *commit) +{ + struct commit_list **pp, *p; + + pp = &commit->parents; + while ((p = *pp) != NULL) { + struct commit *parent = p->item; + if (parent->object.flags & TREESAME) { + *pp = p->next; + free(p); + continue; + } + pp = &p->next; + } +} + static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail) { struct commit_list *p; @@ -1469,6 +1485,13 @@ static struct commit_list **simplify_one(struct rev_info *revs, struct commit *c pst = locate_simplify_state(revs, p->item); p->item = pst->simplified; } + + /* + * A merge with a tree-same parent is useless + */ + if (commit->parents && commit->parents->next) + remove_treesame_parents(commit); + cnt = remove_duplicate_parents(commit); /* diff --git a/t/t6012-rev-list-simplify.sh b/t/t6012-rev-list-simplify.sh index 510bb9679f..d6d79c467f 100755 --- a/t/t6012-rev-list-simplify.sh +++ b/t/t6012-rev-list-simplify.sh @@ -59,7 +59,23 @@ test_expect_success setup ' echo "Final change" >file && test_tick && git commit -a -m "Final change" && - note I + note I && + + git symbolic-ref HEAD refs/heads/unrelated && + git rm -f "*" && + echo "Unrelated branch" >side && + git add side && + test_tick && git commit -m "Side root" && + note J && + + git checkout master && + test_tick && git merge -m "Coolest" unrelated && + note K && + + echo "Immaterial" >elif && + git add elif && + test_tick && git commit -m "Last" && + note L ' FMT='tformat:%P %H | %s' @@ -82,10 +98,10 @@ check_result () { ' } -check_result 'I H G F E D C B A' --full-history -check_result 'I H E C B A' --full-history -- file -check_result 'I H E C B A' --full-history --topo-order -- file -check_result 'I H E C B A' --full-history --date-order -- file +check_result 'L K J I H G F E D C B A' --full-history +check_result 'K I H E C B A' --full-history -- file +check_result 'K I H E C B A' --full-history --topo-order -- file +check_result 'K I H E C B A' --full-history --date-order -- file check_result 'I E C B A' --simplify-merges -- file check_result 'I B A' -- file check_result 'I B A' --topo-order -- file