From patchwork Fri Jan 21 19:12:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elijah Newren X-Patchwork-Id: 12720141 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A088EC433EF for ; Fri, 21 Jan 2022 19:12:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231264AbiAUTM0 (ORCPT ); Fri, 21 Jan 2022 14:12:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231163AbiAUTMZ (ORCPT ); Fri, 21 Jan 2022 14:12:25 -0500 Received: from mail-wr1-x42c.google.com (mail-wr1-x42c.google.com [IPv6:2a00:1450:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E106C06173B for ; Fri, 21 Jan 2022 11:12:25 -0800 (PST) Received: by mail-wr1-x42c.google.com with SMTP id v13so1391940wrv.10 for ; Fri, 21 Jan 2022 11:12:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=tUcb2x3r3ORBLBUjMIsmMGcF0qH+Yuzwxzo0uPqByYM=; b=FrYeIJZ2HQowTSJnl02mziaMfBephZ1q0JlP29TPu0sNcU5XqM5Nhmf7znPwZ6XkuN bEhwrFSeApkM355C4ba2Dvl+756uCbr4/62GhN317pwKj4pmIPi0F7z29u5ZbZaCfSU1 kj/taGrDkBTivEz3ouJpoMxGxjsH2tu9AVBYadb2o+LacOnlTalJIzyDm/Kxsgv4GEDV +426CoxzCVqm+rdizdqcpnHYn07rePpS/QBonfzX/BdjBUa93rL1r7qd0ngK+8CM/R4f Zo7ATdBX2SLzTaNJKts2ao/L7z3BPuFTUtuB8HSn9vwRa7Rhq8UpZjMvh0XUTexvbazB Jx9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=tUcb2x3r3ORBLBUjMIsmMGcF0qH+Yuzwxzo0uPqByYM=; b=3xa3cZ4c5mibXycvX0aUZGwfBugwhABJgOO2umPhThNyAPzpelQcOGNYrC8KcuUXRG OrH/dV8ghaVytQBT0dSnlYqPWNOAuSMu2IJHBaAKzYpmDhI/PXRvwWY0hbqSBpIpw4TO ijixvqCH6FNkiJEZxOnAEXy83vTg7C566+l+/cL78DYZAiEMdiEM7ZGefYrAsEzF2qmP 96BGR1TgnStAFERUbncHd9CH3UCUVePUSXBCAHcRR5zuA0+sWUKgd+U1EtuGC2QmBQzV +hphSpFpzJUu6CCgJ9qgMKTfG5TGdC8lfIpjCN8QHXOJfpG8+6fFEcKlgTEsiWyyfn4G 82Zg== X-Gm-Message-State: AOAM531hBTlPuXIBAglhoF1oTVNpWWspYQcucgRxF03uWaNhnuAjJBgx apqT6yZmRfo4cR12s1HIXchjEU4lL40= X-Google-Smtp-Source: ABdhPJxbkC2gF3oR7FXyMv9sbgli4hJyPCFnhSuijYV8WxV1mJyIDe055secU3LBJw3M49nMFQdvgw== X-Received: by 2002:adf:e8c3:: with SMTP id k3mr4908790wrn.597.1642792343727; Fri, 21 Jan 2022 11:12:23 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id h9sm6576046wmq.8.2022.01.21.11.12.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Jan 2022 11:12:23 -0800 (PST) Message-Id: <0b94724311df34dd10debd43c466695ed406d790.1642792341.git.gitgitgadget@gmail.com> In-Reply-To: References: Date: Fri, 21 Jan 2022 19:12:11 +0000 Subject: [PATCH v4 01/10] show, log: provide a --remerge-diff capability Fcc: Sent MIME-Version: 1.0 To: git@vger.kernel.org Cc: Jeff King , Jonathan Nieder , Sergey Organov , Bagas Sanjaya , Elijah Newren , =?utf-8?b?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason , Neeraj Singh , Johannes Altmanninger , Elijah Newren , Elijah Newren Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Elijah Newren From: Elijah Newren When this option is specified, we remerge all (two parent) merge commits and diff the actual merge commit to the automatically created version, in order to show how users removed conflict markers, resolved the different conflict versions, and potentially added new changes outside of conflict regions in order to resolve semantic merge problems (or, possibly, just to hide other random changes). This capability works by creating a temporary object directory and marking it as the primary object store. This makes it so that any blobs or trees created during the automatic merge are easily removable afterwards by just deleting all objects from the temporary object directory. There are a few ways that this implementation is suboptimal: * `log --remerge-diff` becomes slow, because the temporary object directory can fill with many loose objects while running * the log output can be muddied with misplaced "warning: cannot merge binary files" messages, since ll-merge.c unconditionally writes those messages to stderr while running instead of allowing callers to manage them. * important conflict and warning messages are simply dropped; thus for conflicts like modify/delete or rename/rename or file/directory which are not representable with content conflict markers, there may be no way for a user of --remerge-diff to know that there had been a conflict which was resolved (and which possibly motivated other changes in the merge commit). * when fixing the previous issue, note that some unimportant conflict and warning messages might start being included. We should instead make sure these remain dropped. Subsequent commits will address these issues. Signed-off-by: Elijah Newren --- Documentation/diff-options.txt | 10 +++- builtin/log.c | 14 ++++++ diff-merges.c | 12 +++++ log-tree.c | 59 ++++++++++++++++++++++ revision.h | 3 +- t/t4069-remerge-diff.sh | 90 ++++++++++++++++++++++++++++++++++ 6 files changed, 186 insertions(+), 2 deletions(-) create mode 100755 t/t4069-remerge-diff.sh diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index c89d530d3d1..6b8175defe6 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -34,7 +34,7 @@ endif::git-diff[] endif::git-format-patch[] ifdef::git-log[] ---diff-merges=(off|none|on|first-parent|1|separate|m|combined|c|dense-combined|cc):: +--diff-merges=(off|none|on|first-parent|1|separate|m|combined|c|dense-combined|cc|remerge|r):: --no-diff-merges:: Specify diff format to be used for merge commits. Default is {diff-merges-default} unless `--first-parent` is in use, in which case @@ -64,6 +64,14 @@ ifdef::git-log[] each of the parents. Separate log entry and diff is generated for each parent. + +--diff-merges=remerge::: +--diff-merges=r::: +--remerge-diff::: + With this option, two-parent merge commits are remerged to + create a temporary tree object -- potentially containing files + with conflict markers and such. A diff is then shown between + that temporary tree and the actual merge commit. ++ --diff-merges=combined::: --diff-merges=c::: -c::: diff --git a/builtin/log.c b/builtin/log.c index f75d87e8d7f..846ba0f995a 100644 --- a/builtin/log.c +++ b/builtin/log.c @@ -35,6 +35,7 @@ #include "repository.h" #include "commit-reach.h" #include "range-diff.h" +#include "tmp-objdir.h" #define MAIL_DEFAULT_WRAP 72 #define COVER_FROM_AUTO_MAX_SUBJECT_LEN 100 @@ -406,6 +407,14 @@ static int cmd_log_walk(struct rev_info *rev) struct commit *commit; int saved_nrl = 0; int saved_dcctc = 0; + struct tmp_objdir *remerge_objdir = NULL; + + if (rev->remerge_diff) { + remerge_objdir = tmp_objdir_create("remerge-diff"); + if (!remerge_objdir) + die(_("unable to create temporary object directory")); + tmp_objdir_replace_primary_odb(remerge_objdir, 1); + } if (rev->early_output) setup_early_output(); @@ -449,6 +458,9 @@ static int cmd_log_walk(struct rev_info *rev) rev->diffopt.no_free = 0; diff_free(&rev->diffopt); + if (rev->remerge_diff) + tmp_objdir_destroy(remerge_objdir); + if (rev->diffopt.output_format & DIFF_FORMAT_CHECKDIFF && rev->diffopt.flags.check_failed) { return 02; @@ -1943,6 +1955,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix) die(_("--name-status does not make sense")); if (rev.diffopt.output_format & DIFF_FORMAT_CHECKDIFF) die(_("--check does not make sense")); + if (rev.remerge_diff) + die(_("--remerge-diff does not make sense")); if (!use_patch_format && (!rev.diffopt.output_format || diff --git a/diff-merges.c b/diff-merges.c index 5060ccd890b..0af4b3f9191 100644 --- a/diff-merges.c +++ b/diff-merges.c @@ -17,6 +17,7 @@ static void suppress(struct rev_info *revs) revs->combined_all_paths = 0; revs->merges_imply_patch = 0; revs->merges_need_diff = 0; + revs->remerge_diff = 0; } static void set_separate(struct rev_info *revs) @@ -45,6 +46,12 @@ static void set_dense_combined(struct rev_info *revs) revs->dense_combined_merges = 1; } +static void set_remerge_diff(struct rev_info *revs) +{ + suppress(revs); + revs->remerge_diff = 1; +} + static diff_merges_setup_func_t func_by_opt(const char *optarg) { if (!strcmp(optarg, "off") || !strcmp(optarg, "none")) @@ -57,6 +64,8 @@ static diff_merges_setup_func_t func_by_opt(const char *optarg) return set_combined; else if (!strcmp(optarg, "cc") || !strcmp(optarg, "dense-combined")) return set_dense_combined; + else if (!strcmp(optarg, "r") || !strcmp(optarg, "remerge")) + return set_remerge_diff; else if (!strcmp(optarg, "m") || !strcmp(optarg, "on")) return set_to_default; return NULL; @@ -110,6 +119,9 @@ int diff_merges_parse_opts(struct rev_info *revs, const char **argv) } else if (!strcmp(arg, "--cc")) { set_dense_combined(revs); revs->merges_imply_patch = 1; + } else if (!strcmp(arg, "--remerge-diff")) { + set_remerge_diff(revs); + revs->merges_imply_patch = 1; } else if (!strcmp(arg, "--no-diff-merges")) { suppress(revs); } else if (!strcmp(arg, "--combined-all-paths")) { diff --git a/log-tree.c b/log-tree.c index 644893fd8cf..84ed864fc81 100644 --- a/log-tree.c +++ b/log-tree.c @@ -1,4 +1,5 @@ #include "cache.h" +#include "commit-reach.h" #include "config.h" #include "diff.h" #include "object-store.h" @@ -7,6 +8,7 @@ #include "tag.h" #include "graph.h" #include "log-tree.h" +#include "merge-ort.h" #include "reflog-walk.h" #include "refs.h" #include "string-list.h" @@ -902,6 +904,51 @@ static int do_diff_combined(struct rev_info *opt, struct commit *commit) return !opt->loginfo; } +static int do_remerge_diff(struct rev_info *opt, + struct commit_list *parents, + struct object_id *oid, + struct commit *commit) +{ + struct merge_options o; + struct commit_list *bases; + struct merge_result res = {0}; + struct pretty_print_context ctx = {0}; + struct commit *parent1 = parents->item; + struct commit *parent2 = parents->next->item; + struct strbuf parent1_desc = STRBUF_INIT; + struct strbuf parent2_desc = STRBUF_INIT; + + /* Setup merge options */ + init_merge_options(&o, the_repository); + o.show_rename_progress = 0; + + ctx.abbrev = DEFAULT_ABBREV; + format_commit_message(parent1, "%h (%s)", &parent1_desc, &ctx); + format_commit_message(parent2, "%h (%s)", &parent2_desc, &ctx); + o.branch1 = parent1_desc.buf; + o.branch2 = parent2_desc.buf; + + /* Parse the relevant commits and get the merge bases */ + parse_commit_or_die(parent1); + parse_commit_or_die(parent2); + bases = get_merge_bases(parent1, parent2); + + /* Re-merge the parents */ + merge_incore_recursive(&o, bases, parent1, parent2, &res); + + /* Show the diff */ + diff_tree_oid(&res.tree->object.oid, oid, "", &opt->diffopt); + log_tree_diff_flush(opt); + + /* Cleanup */ + strbuf_release(&parent1_desc); + strbuf_release(&parent2_desc); + merge_finalize(&o, &res); + /* TODO: clean up the temporary object directory */ + + return !opt->loginfo; +} + /* * Show the diff of a commit. * @@ -936,6 +983,18 @@ static int log_tree_diff(struct rev_info *opt, struct commit *commit, struct log } if (is_merge) { + int octopus = (parents->next->next != NULL); + + if (opt->remerge_diff) { + if (octopus) { + show_log(opt); + fprintf(opt->diffopt.file, + "diff: warning: Skipping remerge-diff " + "for octopus merges.\n"); + return 1; + } + return do_remerge_diff(opt, parents, oid, commit); + } if (opt->combine_merges) return do_diff_combined(opt, commit); if (opt->separate_merges) { diff --git a/revision.h b/revision.h index 5578bb4720a..13178e6b8f3 100644 --- a/revision.h +++ b/revision.h @@ -195,7 +195,8 @@ struct rev_info { combine_merges:1, combined_all_paths:1, dense_combined_merges:1, - first_parent_merges:1; + first_parent_merges:1, + remerge_diff:1; /* Format info */ int show_notes; diff --git a/t/t4069-remerge-diff.sh b/t/t4069-remerge-diff.sh new file mode 100755 index 00000000000..5ef191f4fc9 --- /dev/null +++ b/t/t4069-remerge-diff.sh @@ -0,0 +1,90 @@ +#!/bin/sh + +test_description='remerge-diff handling' + +. ./test-lib.sh + +# This test is ort-specific +test "${GIT_TEST_MERGE_ALGORITHM:-ort}" = ort || { + skip_all="GIT_TEST_MERGE_ALGORITHM != ort" + test_done +} + +test_expect_success 'setup basic merges' ' + test_write_lines 1 2 3 4 5 6 7 8 9 >numbers && + git add numbers && + git commit -m base && + + git branch feature_a && + git branch feature_b && + git branch feature_c && + + git branch ab_resolution && + git branch bc_resolution && + + git checkout feature_a && + test_write_lines 1 2 three 4 5 6 7 eight 9 >numbers && + git commit -a -m change_a && + + git checkout feature_b && + test_write_lines 1 2 tres 4 5 6 7 8 9 >numbers && + git commit -a -m change_b && + + git checkout feature_c && + test_write_lines 1 2 3 4 5 6 7 8 9 10 >numbers && + git commit -a -m change_c && + + git checkout bc_resolution && + git merge --ff-only feature_b && + # no conflict + git merge feature_c && + + git checkout ab_resolution && + git merge --ff-only feature_a && + # conflicts! + test_must_fail git merge feature_b && + # Resolve conflict...and make another change elsewhere + test_write_lines 1 2 drei 4 5 6 7 acht 9 >numbers && + git add numbers && + git merge --continue +' + +test_expect_success 'remerge-diff on a clean merge' ' + git log -1 --oneline bc_resolution >expect && + git show --oneline --remerge-diff bc_resolution >actual && + test_cmp expect actual +' + +test_expect_success 'remerge-diff with both a resolved conflict and an unrelated change' ' + git log -1 --oneline ab_resolution >tmp && + cat <<-EOF >>tmp && + diff --git a/numbers b/numbers + index a1fb731..6875544 100644 + --- a/numbers + +++ b/numbers + @@ -1,13 +1,9 @@ + 1 + 2 + -<<<<<<< b0ed5cb (change_a) + -three + -======= + -tres + ->>>>>>> 6cd3f82 (change_b) + +drei + 4 + 5 + 6 + 7 + -eight + +acht + 9 + EOF + # Hashes above are sha1; rip them out so test works with sha256 + sed -e "s/[0-9a-f]\{7,\}/HASH/g" tmp >expect && + + git show --oneline --remerge-diff ab_resolution >tmp && + sed -e "s/[0-9a-f]\{7,\}/HASH/g" tmp >actual && + test_cmp expect actual +' + +test_done