From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: Multi-ancestor read-tree notes Date: Tue, 06 Sep 2005 13:03:28 -0700 Message-ID: <7vbr36j75b.fsf@assigned-by-dhcp.cox.net> References: <7virxeycod.fsf@assigned-by-dhcp.cox.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: git@vger.kernel.org X-From: git-owner@vger.kernel.org Tue Sep 06 22:05:41 2005 Return-path: Received: from vger.kernel.org ([209.132.176.167]) by ciao.gmane.org with esmtp (Exim 4.43) id 1ECjfp-0004jG-K7 for gcvg-git@gmane.org; Tue, 06 Sep 2005 22:04:05 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750852AbVIFUDj (ORCPT ); Tue, 6 Sep 2005 16:03:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750858AbVIFUDj (ORCPT ); Tue, 6 Sep 2005 16:03:39 -0400 Received: from fed1rmmtao10.cox.net ([68.230.241.29]:29639 "EHLO fed1rmmtao10.cox.net") by vger.kernel.org with ESMTP id S1750857AbVIFUDi (ORCPT ); Tue, 6 Sep 2005 16:03:38 -0400 Received: from assigned-by-dhcp.cox.net ([68.4.9.127]) by fed1rmmtao10.cox.net (InterMail vM.6.01.05.02 201-2131-123-102-20050715) with ESMTP id <20050906200330.DHYN3414.fed1rmmtao10.cox.net@assigned-by-dhcp.cox.net>; Tue, 6 Sep 2005 16:03:30 -0400 To: Daniel Barkalow User-Agent: Gnus/5.110004 (No Gnus v0.4) Emacs/21.4 (gnu/linux) Sender: git-owner@vger.kernel.org Precedence: bulk X-Mailing-List: git@vger.kernel.org Archived-At: Daniel Barkalow writes: > Do you know if there's anything like case #16 in there? I'd be interested > to know if there's anything that gets handled automatically in different > ways depending on which single base is used, and doesn't require manual > intervention with multiple bases, because that's probably wrong. Re-running the tests with the attached patch shows there weren't any. > I didn't want to break the assumption of only one entry per stage in the > initial version. I'm also not sure that listing the ancestors is > particularly useful in this case. They have to be exactly the contents of > stages 2 and 3, plus possibly more stuff that's not been kept by either > side. Ah, I see, that's true. > Great. Want me to send the patches with better organization, or are you > set with what I've sent? That's up to you. If you are content with what I have in the pu branch, there is no need to bother resending. OTOH if you have further clean-ups in mind, i.e. "better organization" above, I do not mind dropping the current ones from "pu" and replace them with another set from you. ------------ [PATCH] Add debugging help for case #16 to read-tree.c This will help us detect if real-world example merges have multiple merge-base candidates and one of them matches one head while another matches the other head. Signed-off-by: Junio C Hamano --- read-tree.c | 36 ++++++++++++++++++++++++++++-------- t/t1000-read-tree-m-3way.sh | 16 ++++++++++++++++ 2 files changed, 44 insertions(+), 8 deletions(-) 6405d0aa729f4b060123e1235b3ddc074fdd01b7 diff --git a/read-tree.c b/read-tree.c --- a/read-tree.c +++ b/read-tree.c @@ -3,6 +3,8 @@ * * Copyright (C) Linus Torvalds, 2005 */ +#define DBRT_DEBUG 1 + #include "cache.h" #include "object.h" @@ -47,8 +49,6 @@ static int entcmp(char *name1, int dir1, return ret; } -#define DBRT_DEBUG 0 - static int unpack_trees_rec(struct tree_entry_list **posns, int len, const char *base, merge_fn_t fn, int *indpos) { @@ -101,14 +101,14 @@ static int unpack_trees_rec(struct tree_ } } -#if DBRT_DEBUG +#if DBRT_DEBUG > 1 if (first) printf("index %s\n", first); #endif for (i = 0; i < len; i++) { if (!posns[i] || posns[i] == &df_conflict_list) continue; -#if DBRT_DEBUG +#if DBRT_DEBUG > 1 printf("%d %s\n", i + 1, posns[i]->name); #endif if (!first || entcmp(first, firstdir, @@ -188,7 +188,7 @@ static int unpack_trees_rec(struct tree_ if (merge) { int ret; -#if DBRT_DEBUG +#if DBRT_DEBUG > 1 printf("%s:\n", first); for (i = 0; i < src_size; i++) { printf(" %d ", i); @@ -200,7 +200,7 @@ static int unpack_trees_rec(struct tree_ #endif ret = fn(src); -#if DBRT_DEBUG +#if DBRT_DEBUG > 1 printf("Added %d entries\n", ret); #endif *indpos += ret; @@ -353,6 +353,19 @@ static int keep_entry(struct cache_entry return 1; } +#if DBRT_DEBUG +static void show_stage_entry(FILE *o, + const char *label, const struct cache_entry *ce) +{ + fprintf(stderr, "%s%06o %s %d\t%s\n", + label, + ntohl(ce->ce_mode), + sha1_to_hex(ce->sha1), + ce_stage(ce), + ce->name); +} +#endif + static int threeway_merge(struct cache_entry **stages) { struct cache_entry *index; @@ -392,10 +405,10 @@ static int threeway_merge(struct cache_e if (!same(remote, head)) { for (i = 1; i < head_idx; i++) { if (same(stages[i], head)) { - head_match = 1; + head_match = i; } if (same(stages[i], remote)) { - remote_match = 1; + remote_match = i; } } } @@ -450,6 +463,13 @@ static int threeway_merge(struct cache_e } } } +#if DBRT_DEBUG + else { + fprintf(stderr, "read-tree: warning #16 detected\n"); + show_stage_entry(stderr, "head ", stages[head_match]); + show_stage_entry(stderr, "remote ", stages[remote_match]); + } +#endif if (head) { count += keep_entry(head); } if (remote) { count += keep_entry(remote); } return count; diff --git a/t/t1000-read-tree-m-3way.sh b/t/t1000-read-tree-m-3way.sh --- a/t/t1000-read-tree-m-3way.sh +++ b/t/t1000-read-tree-m-3way.sh @@ -218,6 +218,9 @@ currently implemented. or (2) match B. ------------------------------------------------------------------ 15 exists O==A O==B take B must match A if exists. + ------------------------------------------------------------------ + 16 exists O==A O==B barf must match A if exists. + *multi* in one in another ------------------------------------------------------------------- Note: if we want to implement 2ALT and 3ALT we need to be careful. @@ -514,4 +517,17 @@ test_expect_failure \ git-update-cache --add NN && git-read-tree -m $tree_O $tree_A $tree_B" +# #16 +test_expect_success \ + '16 - A matches in one and B matches in another.' \ + 'rm -f .git/index F16 && + echo F16 >F16 && + git-update-cache --add F16 && + tree0=`git-write-tree` && + echo E16 >F16 && + git-update-cache F16 && + tree1=`git-write-tree` && + git-read-tree -m $tree0 $tree1 $tree1 $tree0 && + git-ls-files --stage' + test_done