From 70176b70156f02bf4345ee091e664430f58ab32b Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:44 +0000 Subject: [PATCH 01/17] merge-tree: rename merge_trees() to trivial_merge_trees() merge-recursive.h defined its own merge_trees() function, different than the one found in builtin/merge-tree.c. That was okay in the past, but we want merge-tree to be able to use the merge-ort functions, which will end up including merge-recursive.h. Rename the function found in builtin/merge-tree.c to avoid the conflict. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- builtin/merge-tree.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 5dc94d6f88..06f9eee9f7 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -28,7 +28,7 @@ static void add_merge_entry(struct merge_list *entry) merge_result_end = &entry->next; } -static void merge_trees(struct tree_desc t[3], const char *base); +static void trivial_merge_trees(struct tree_desc t[3], const char *base); static const char *explanation(struct merge_list *entry) { @@ -225,7 +225,7 @@ static void unresolved_directory(const struct traverse_info *info, buf2 = fill_tree_descriptor(r, t + 2, ENTRY_OID(n + 2)); #undef ENTRY_OID - merge_trees(t, newbase); + trivial_merge_trees(t, newbase); free(buf0); free(buf1); @@ -342,7 +342,7 @@ static int threeway_callback(int n, unsigned long mask, unsigned long dirmask, s return mask; } -static void merge_trees(struct tree_desc t[3], const char *base) +static void trivial_merge_trees(struct tree_desc t[3], const char *base) { struct traverse_info info; @@ -378,7 +378,7 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) buf1 = get_tree_descriptor(r, t+0, argv[1]); buf2 = get_tree_descriptor(r, t+1, argv[2]); buf3 = get_tree_descriptor(r, t+2, argv[3]); - merge_trees(t, ""); + trivial_merge_trees(t, ""); free(buf1); free(buf2); free(buf3); From 55e48f6bf76f9038eef1a6926533a7c30a53c923 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:45 +0000 Subject: [PATCH 02/17] merge-tree: move logic for existing merge into new function In preparation for adding a non-trivial merge capability to merge-tree, move the existing merge logic for trivial merges into a new function. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- builtin/merge-tree.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 06f9eee9f7..914ec960b7 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -366,15 +366,12 @@ static void *get_tree_descriptor(struct repository *r, return buf; } -int cmd_merge_tree(int argc, const char **argv, const char *prefix) +static int trivial_merge(int argc, const char **argv) { struct repository *r = the_repository; struct tree_desc t[3]; void *buf1, *buf2, *buf3; - if (argc != 4) - usage(merge_tree_usage); - buf1 = get_tree_descriptor(r, t+0, argv[1]); buf2 = get_tree_descriptor(r, t+1, argv[2]); buf3 = get_tree_descriptor(r, t+2, argv[3]); @@ -386,3 +383,10 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) show_result(); return 0; } + +int cmd_merge_tree(int argc, const char **argv, const char *prefix) +{ + if (argc != 4) + usage(merge_tree_usage); + return trivial_merge(argc, argv); +} From 6ec755a0e152dfb0ed6bffa70b511c45a1f29ebd Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:46 +0000 Subject: [PATCH 03/17] merge-tree: add option parsing and initial shell for real merge function Let merge-tree accept a `--write-tree` parameter for choosing real merges instead of trivial merges, and accept an optional `--trivial-merge` option to get the traditional behavior. Note that these accept different numbers of arguments, though, so these names need not actually be used. Note that real merges differ from trivial merges in that they handle: - three way content merges - recursive ancestor consolidation - renames - proper directory/file conflict handling - etc. Basically all the stuff you'd expect from `git merge`, just without updating the index and working tree. The initial shell added here does nothing more than die with "real merges are not yet implemented", but that will be fixed in subsequent commits. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- builtin/merge-tree.c | 84 +++++++++++++++++++++++++++++++++++++++----- git.c | 2 +- 2 files changed, 76 insertions(+), 10 deletions(-) diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 914ec960b7..0f9d928e86 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -3,13 +3,12 @@ #include "tree-walk.h" #include "xdiff-interface.h" #include "object-store.h" +#include "parse-options.h" #include "repository.h" #include "blob.h" #include "exec-cmd.h" #include "merge-blobs.h" -static const char merge_tree_usage[] = "git merge-tree "; - struct merge_list { struct merge_list *next; struct merge_list *link; /* other stages for this object */ @@ -366,15 +365,17 @@ static void *get_tree_descriptor(struct repository *r, return buf; } -static int trivial_merge(int argc, const char **argv) +static int trivial_merge(const char *base, + const char *branch1, + const char *branch2) { struct repository *r = the_repository; struct tree_desc t[3]; void *buf1, *buf2, *buf3; - buf1 = get_tree_descriptor(r, t+0, argv[1]); - buf2 = get_tree_descriptor(r, t+1, argv[2]); - buf3 = get_tree_descriptor(r, t+2, argv[3]); + buf1 = get_tree_descriptor(r, t+0, base); + buf2 = get_tree_descriptor(r, t+1, branch1); + buf3 = get_tree_descriptor(r, t+2, branch2); trivial_merge_trees(t, ""); free(buf1); free(buf2); @@ -384,9 +385,74 @@ static int trivial_merge(int argc, const char **argv) return 0; } +enum mode { + MODE_UNKNOWN, + MODE_TRIVIAL, + MODE_REAL, +}; + +struct merge_tree_options { + int mode; +}; + +static int real_merge(struct merge_tree_options *o, + const char *branch1, const char *branch2) +{ + die(_("real merges are not yet implemented")); +} + int cmd_merge_tree(int argc, const char **argv, const char *prefix) { - if (argc != 4) - usage(merge_tree_usage); - return trivial_merge(argc, argv); + struct merge_tree_options o = { 0 }; + int expected_remaining_argc; + + const char * const merge_tree_usage[] = { + N_("git merge-tree [--write-tree] "), + N_("git merge-tree [--trivial-merge] "), + NULL + }; + struct option mt_options[] = { + OPT_CMDMODE(0, "write-tree", &o.mode, + N_("do a real merge instead of a trivial merge"), + MODE_REAL), + OPT_CMDMODE(0, "trivial-merge", &o.mode, + N_("do a trivial merge only"), MODE_TRIVIAL), + OPT_END() + }; + + /* Parse arguments */ + argc = parse_options(argc, argv, prefix, mt_options, + merge_tree_usage, PARSE_OPT_STOP_AT_NON_OPTION); + switch (o.mode) { + default: + BUG("unexpected command mode %d", o.mode); + case MODE_UNKNOWN: + switch (argc) { + default: + usage_with_options(merge_tree_usage, mt_options); + case 2: + o.mode = MODE_REAL; + break; + case 3: + o.mode = MODE_TRIVIAL; + break; + } + expected_remaining_argc = argc; + break; + case MODE_REAL: + expected_remaining_argc = 2; + break; + case MODE_TRIVIAL: + expected_remaining_argc = 3; + break; + } + + if (argc != expected_remaining_argc) + usage_with_options(merge_tree_usage, mt_options); + + /* Do the relevant type of merge */ + if (o.mode == MODE_REAL) + return real_merge(&o, argv[0], argv[1]); + else + return trivial_merge(argv[0], argv[1], argv[2]); } diff --git a/git.c b/git.c index d7a7a82008..e5d62fa5a9 100644 --- a/git.c +++ b/git.c @@ -565,7 +565,7 @@ static struct cmd_struct commands[] = { { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT }, { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT }, { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT }, - { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT }, + { "merge-tree", cmd_merge_tree, RUN_SETUP }, { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT }, { "mktree", cmd_mktree, RUN_SETUP }, { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP }, From 1f0c3a29da3515d88537902cd267cc726020eea5 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:47 +0000 Subject: [PATCH 04/17] merge-tree: implement real merges This adds the ability to perform real merges rather than just trivial merges (meaning handling three way content merges, recursive ancestor consolidation, renames, proper directory/file conflict handling, and so forth). However, unlike `git merge`, the working tree and index are left alone and no branch is updated. The only output is: - the toplevel resulting tree printed on stdout - exit status of 0 (clean), 1 (conflicts present), anything else (merge could not be performed; unknown if clean or conflicted) This output is meant to be used by some higher level script, perhaps in a sequence of steps like this: NEWTREE=$(git merge-tree --write-tree $BRANCH1 $BRANCH2) test $? -eq 0 || die "There were conflicts..." NEWCOMMIT=$(git commit-tree $NEWTREE -p $BRANCH1 -p $BRANCH2) git update-ref $BRANCH1 $NEWCOMMIT Note that higher level scripts may also want to access the conflict/warning messages normally output during a merge, or have quick access to a list of files with conflicts. That is not available in this preliminary implementation, but subsequent commits will add that ability (meaning that NEWTREE would be a lot more than a tree in the case of conflicts). This also marks the traditional trivial merge of merge-tree as deprecated. The trivial merge not only had limited applicability, the output format was also difficult to work with (and its format undocumented), and will generally be less performant than real merges. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- Documentation/git-merge-tree.txt | 96 ++++++++++++++++++++++++---- builtin/merge-tree.c | 41 +++++++++++- t/t4301-merge-tree-write-tree.sh | 106 +++++++++++++++++++++++++++++++ 3 files changed, 231 insertions(+), 12 deletions(-) create mode 100755 t/t4301-merge-tree-write-tree.sh diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt index 58731c1942..2a9c91328d 100644 --- a/Documentation/git-merge-tree.txt +++ b/Documentation/git-merge-tree.txt @@ -3,26 +3,100 @@ git-merge-tree(1) NAME ---- -git-merge-tree - Show three-way merge without touching index +git-merge-tree - Perform merge without touching index or working tree SYNOPSIS -------- [verse] -'git merge-tree' +'git merge-tree' [--write-tree] +'git merge-tree' [--trivial-merge] (deprecated) +[[NEWMERGE]] DESCRIPTION ----------- -Reads three tree-ish, and output trivial merge results and -conflicting stages to the standard output. This is similar to -what three-way 'git read-tree -m' does, but instead of storing the -results in the index, the command outputs the entries to the -standard output. -This is meant to be used by higher level scripts to compute -merge results outside of the index, and stuff the results back into the -index. For this reason, the output from the command omits -entries that match the tree. +This command has a modern `--write-tree` mode and a deprecated +`--trivial-merge` mode. With the exception of the +<> section at the end, the rest of +this documentation describes modern `--write-tree` mode. + +Performs a merge, but does not make any new commits and does not read +from or write to either the working tree or index. + +The performed merge will use the same feature as the "real" +linkgit:git-merge[1], including: + + * three way content merges of individual files + * rename detection + * proper directory/file conflict handling + * recursive ancestor consolidation (i.e. when there is more than one + merge base, creating a virtual merge base by merging the merge bases) + * etc. + +After the merge completes, a new toplevel tree object is created. See +`OUTPUT` below for details. + +[[OUTPUT]] +OUTPUT +------ + +For either a successful or conflicted merge, the output from +git-merge-tree is simply one line: + + + +The printed tree object corresponds to what would be checked out in +the working tree at the end of `git merge`, and thus may have files +with conflict markers in them. + +EXIT STATUS +----------- + +For a successful, non-conflicted merge, the exit status is 0. When the +merge has conflicts, the exit status is 1. If the merge is not able to +complete (or start) due to some kind of error, the exit status is +something other than 0 or 1 (and the output is unspecified). + +USAGE NOTES +----------- + +This command is intended as low-level plumbing, similar to +linkgit:git-hash-object[1], linkgit:git-mktree[1], +linkgit:git-commit-tree[1], linkgit:git-write-tree[1], +linkgit:git-update-ref[1], and linkgit:git-mktag[1]. Thus, it can be +used as a part of a series of steps such as: + + NEWTREE=$(git merge-tree --write-tree $BRANCH1 $BRANCH2) + test $? -eq 0 || die "There were conflicts..." + NEWCOMMIT=$(git commit-tree $NEWTREE -p $BRANCH1 -p $BRANCH2) + git update-ref $BRANCH1 $NEWCOMMIT + +[[DEPMERGE]] +DEPRECATED DESCRIPTION +---------------------- + +Per the <> and unlike the rest of this +documentation, this section describes the deprecated `--trivial-merge` +mode. + +Other than the optional `--trivial-merge`, this mode accepts no +options. + +This mode reads three tree-ish, and outputs trivial merge results and +conflicting stages to the standard output in a semi-diff format. +Since this was designed for higher level scripts to consume and merge +the results back into the index, it omits entries that match +. The result of this second form is similar to what +three-way 'git read-tree -m' does, but instead of storing the results +in the index, the command outputs the entries to the standard output. + +This form not only has limited applicability (a trivial merge cannot +handle content merges of individual files, rename detection, proper +directory/file conflict handling, etc.), the output format is also +difficult to work with, and it will generally be less performant than +the first form even on successful merges (especially if working in +large repositories). GIT --- diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 0f9d928e86..2332525d8b 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -2,6 +2,9 @@ #include "builtin.h" #include "tree-walk.h" #include "xdiff-interface.h" +#include "help.h" +#include "commit-reach.h" +#include "merge-ort.h" #include "object-store.h" #include "parse-options.h" #include "repository.h" @@ -398,7 +401,43 @@ struct merge_tree_options { static int real_merge(struct merge_tree_options *o, const char *branch1, const char *branch2) { - die(_("real merges are not yet implemented")); + struct commit *parent1, *parent2; + struct commit_list *merge_bases = NULL; + struct merge_options opt; + struct merge_result result = { 0 }; + + parent1 = get_merge_parent(branch1); + if (!parent1) + help_unknown_ref(branch1, "merge-tree", + _("not something we can merge")); + + parent2 = get_merge_parent(branch2); + if (!parent2) + help_unknown_ref(branch2, "merge-tree", + _("not something we can merge")); + + init_merge_options(&opt, the_repository); + + opt.show_rename_progress = 0; + + opt.branch1 = branch1; + opt.branch2 = branch2; + + /* + * Get the merge bases, in reverse order; see comment above + * merge_incore_recursive in merge-ort.h + */ + merge_bases = get_merge_bases(parent1, parent2); + if (!merge_bases) + die(_("refusing to merge unrelated histories")); + merge_bases = reverse_commit_list(merge_bases); + + merge_incore_recursive(&opt, merge_bases, parent1, parent2, &result); + if (result.clean < 0) + die(_("failure to merge")); + puts(oid_to_hex(&result.tree->object.oid)); + merge_finalize(&opt, &result); + return !result.clean; /* result.clean < 0 handled above */ } int cmd_merge_tree(int argc, const char **argv, const char *prefix) diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh new file mode 100755 index 0000000000..6d321652e2 --- /dev/null +++ b/t/t4301-merge-tree-write-tree.sh @@ -0,0 +1,106 @@ +#!/bin/sh + +test_description='git merge-tree --write-tree' + +. ./test-lib.sh + +# This test is ort-specific +if test "$GIT_TEST_MERGE_ALGORITHM" != "ort" +then + skip_all="GIT_TEST_MERGE_ALGORITHM != ort" + test_done +fi + +test_expect_success setup ' + test_write_lines 1 2 3 4 5 >numbers && + echo hello >greeting && + echo foo >whatever && + git add numbers greeting whatever && + test_tick && + git commit -m initial && + + git branch side1 && + git branch side2 && + git branch side3 && + + git checkout side1 && + test_write_lines 1 2 3 4 5 6 >numbers && + echo hi >greeting && + echo bar >whatever && + git add numbers greeting whatever && + test_tick && + git commit -m modify-stuff && + + git checkout side2 && + test_write_lines 0 1 2 3 4 5 >numbers && + echo yo >greeting && + git rm whatever && + mkdir whatever && + >whatever/empty && + git add numbers greeting whatever/empty && + test_tick && + git commit -m other-modifications && + + git checkout side3 && + git mv numbers sequence && + test_tick && + git commit -m rename-numbers +' + +test_expect_success 'Clean merge' ' + TREE_OID=$(git merge-tree --write-tree side1 side3) && + q_to_tab <<-EOF >expect && + 100644 blob $(git rev-parse side1:greeting)Qgreeting + 100644 blob $(git rev-parse side1:numbers)Qsequence + 100644 blob $(git rev-parse side1:whatever)Qwhatever + EOF + + git ls-tree $TREE_OID >actual && + test_cmp expect actual +' + +test_expect_success 'Content merge and a few conflicts' ' + git checkout side1^0 && + test_must_fail git merge side2 && + expected_tree=$(git rev-parse AUTO_MERGE) && + + # We will redo the merge, while we are still in a conflicted state! + test_when_finished "git reset --hard" && + + test_expect_code 1 git merge-tree --write-tree side1 side2 >RESULT && + actual_tree=$(head -n 1 RESULT) && + + # Due to differences of e.g. "HEAD" vs "side1", the results will not + # exactly match. Dig into individual files. + + # Numbers should have three-way merged cleanly + test_write_lines 0 1 2 3 4 5 6 >expect && + git show ${actual_tree}:numbers >actual && + test_cmp expect actual && + + # whatever and whatever~ should have same HASHES + git rev-parse ${expected_tree}:whatever ${expected_tree}:whatever~HEAD >expect && + git rev-parse ${actual_tree}:whatever ${actual_tree}:whatever~side1 >actual && + test_cmp expect actual && + + # greeting should have a merge conflict + git show ${expected_tree}:greeting >tmp && + sed -e s/HEAD/side1/ tmp >expect && + git show ${actual_tree}:greeting >actual && + test_cmp expect actual +' + +test_expect_success 'Barf on misspelled option, with exit code other than 0 or 1' ' + # Mis-spell with single "s" instead of double "s" + test_expect_code 129 git merge-tree --write-tree --mesages FOOBAR side1 side2 2>expect && + + grep "error: unknown option.*mesages" expect +' + +test_expect_success 'Barf on too many arguments' ' + test_expect_code 129 git merge-tree --write-tree side1 side2 invalid 2>expect && + + grep "^usage: git merge-tree" expect +' + +test_done From a34edae68a26f8f97f6ba69f408abbd3480ed90c Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:48 +0000 Subject: [PATCH 05/17] merge-ort: split out a separate display_update_messages() function This patch includes no new code; it simply moves a bunch of lines into a new function. As such, there are no functional changes. This is just a preparatory step to allow the printed messages to be handled differently by other callers, such as in `git merge-tree --write-tree`. (Patch best viewed with --color-moved --color-moved-ws=allow-indentation-change to see that it is a simple code movement.) Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- merge-ort.c | 78 ++++++++++++++++++++++++++++------------------------- merge-ort.h | 8 ++++++ 2 files changed, 49 insertions(+), 37 deletions(-) diff --git a/merge-ort.c b/merge-ort.c index b5015b9afd..3c6d0577de 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -4257,6 +4257,45 @@ static int record_conflicted_index_entries(struct merge_options *opt) return errs; } +void merge_display_update_messages(struct merge_options *opt, + struct merge_result *result) +{ + struct merge_options_internal *opti = result->priv; + struct hashmap_iter iter; + struct strmap_entry *e; + struct string_list olist = STRING_LIST_INIT_NODUP; + int i; + + if (opt->record_conflict_msgs_as_headers) + BUG("Either display conflict messages or record them as headers, not both"); + + trace2_region_enter("merge", "display messages", opt->repo); + + /* Hack to pre-allocate olist to the desired size */ + ALLOC_GROW(olist.items, strmap_get_size(&opti->output), + olist.alloc); + + /* Put every entry from output into olist, then sort */ + strmap_for_each_entry(&opti->output, &iter, e) { + string_list_append(&olist, e->key)->util = e->value; + } + string_list_sort(&olist); + + /* Iterate over the items, printing them */ + for (i = 0; i < olist.nr; ++i) { + struct strbuf *sb = olist.items[i].util; + + printf("%s", sb->buf); + } + string_list_clear(&olist, 0); + + /* Also include needed rename limit adjustment now */ + diff_warn_rename_limit("merge.renamelimit", + opti->renames.needed_limit, 0); + + trace2_region_leave("merge", "display messages", opt->repo); +} + void merge_switch_to_result(struct merge_options *opt, struct tree *head, struct merge_result *result, @@ -4294,43 +4333,8 @@ void merge_switch_to_result(struct merge_options *opt, fclose(fp); trace2_region_leave("merge", "write_auto_merge", opt->repo); } - - if (display_update_msgs) { - struct merge_options_internal *opti = result->priv; - struct hashmap_iter iter; - struct strmap_entry *e; - struct string_list olist = STRING_LIST_INIT_NODUP; - int i; - - if (opt->record_conflict_msgs_as_headers) - BUG("Either display conflict messages or record them as headers, not both"); - - trace2_region_enter("merge", "display messages", opt->repo); - - /* Hack to pre-allocate olist to the desired size */ - ALLOC_GROW(olist.items, strmap_get_size(&opti->output), - olist.alloc); - - /* Put every entry from output into olist, then sort */ - strmap_for_each_entry(&opti->output, &iter, e) { - string_list_append(&olist, e->key)->util = e->value; - } - string_list_sort(&olist); - - /* Iterate over the items, printing them */ - for (i = 0; i < olist.nr; ++i) { - struct strbuf *sb = olist.items[i].util; - - printf("%s", sb->buf); - } - string_list_clear(&olist, 0); - - /* Also include needed rename limit adjustment now */ - diff_warn_rename_limit("merge.renamelimit", - opti->renames.needed_limit, 0); - - trace2_region_leave("merge", "display messages", opt->repo); - } + if (display_update_msgs) + merge_display_update_messages(opt, result); merge_finalize(opt, result); } diff --git a/merge-ort.h b/merge-ort.h index fe599b8786..e5aec45b18 100644 --- a/merge-ort.h +++ b/merge-ort.h @@ -80,6 +80,14 @@ void merge_switch_to_result(struct merge_options *opt, int update_worktree_and_index, int display_update_msgs); +/* + * Display messages about conflicts and which files were 3-way merged. + * Automatically called by merge_switch_to_result() with stream == stdout, + * so only call this when bypassing merge_switch_to_result(). + */ +void merge_display_update_messages(struct merge_options *opt, + struct merge_result *result); + /* Do needed cleanup when not calling merge_switch_to_result() */ void merge_finalize(struct merge_options *opt, struct merge_result *result); From a1a7811975e4e3d872379ab03acab9506933de9c Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:49 +0000 Subject: [PATCH 06/17] merge-tree: support including merge messages in output When running `git merge-tree --write-tree`, we previously would only return an exit status reflecting the cleanness of a merge, and print out the toplevel tree of the resulting merge. Merges also have informational messages, such as: * "Auto-merging " * "CONFLICT (content): ..." * "CONFLICT (file/directory)" * etc. In fact, when non-content conflicts occur (such as file/directory, modify/delete, add/add with differing modes, rename/rename (1to2), etc.), these informational messages may be the only notification the user gets since these conflicts are not representable in the contents of the file. Add a --[no-]messages option so that callers can request these messages be included at the end of the output. Include such messages by default when there are conflicts, and omit them by default when the merge is clean. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- Documentation/git-merge-tree.txt | 47 ++++++++++++++++++++++++++++---- builtin/merge-tree.c | 21 ++++++++++++-- t/t4301-merge-tree-write-tree.sh | 37 +++++++++++++++++++++++++ 3 files changed, 97 insertions(+), 8 deletions(-) diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt index 2a9c91328d..25b462be14 100644 --- a/Documentation/git-merge-tree.txt +++ b/Documentation/git-merge-tree.txt @@ -9,7 +9,7 @@ git-merge-tree - Perform merge without touching index or working tree SYNOPSIS -------- [verse] -'git merge-tree' [--write-tree] +'git merge-tree' [--write-tree] [] 'git merge-tree' [--trivial-merge] (deprecated) [[NEWMERGE]] @@ -37,18 +37,50 @@ linkgit:git-merge[1], including: After the merge completes, a new toplevel tree object is created. See `OUTPUT` below for details. +OPTIONS +------- + +--[no-]messages:: + Write any informational messages such as "Auto-merging " + or CONFLICT notices to the end of stdout. If unspecified, the + default is to include these messages if there are merge + conflicts, and to omit them otherwise. + [[OUTPUT]] OUTPUT ------ -For either a successful or conflicted merge, the output from -git-merge-tree is simply one line: +For a successful merge, the output from git-merge-tree is simply one +line: -The printed tree object corresponds to what would be checked out in -the working tree at the end of `git merge`, and thus may have files -with conflict markers in them. +Whereas for a conflicted merge, the output is by default of the form: + + + + +These are discussed individually below. + +[[OIDTLT]] +OID of toplevel tree +~~~~~~~~~~~~~~~~~~~~ + +This is a tree object that represents what would be checked out in the +working tree at the end of `git merge`. If there were conflicts, then +files within this tree may have embedded conflict markers. + +[[IM]] +Informational messages +~~~~~~~~~~~~~~~~~~~~~~ + +This always starts with a blank line to separate it from the previous +section, and then has free-form messages about the merge, such as: + + * "Auto-merging " + * "CONFLICT (rename/delete): renamed...but deleted in..." + * "Failed to merge submodule ()" + * "Warning: cannot merge binary files: " EXIT STATUS ----------- @@ -72,6 +104,9 @@ used as a part of a series of steps such as: NEWCOMMIT=$(git commit-tree $NEWTREE -p $BRANCH1 -p $BRANCH2) git update-ref $BRANCH1 $NEWCOMMIT +Note that when the exit status is non-zero, `NEWTREE` in this sequence +will contain a lot more output than just a tree. + [[DEPMERGE]] DEPRECATED DESCRIPTION ---------------------- diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 2332525d8b..831d9c7758 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -396,6 +396,7 @@ enum mode { struct merge_tree_options { int mode; + int show_messages; }; static int real_merge(struct merge_tree_options *o, @@ -435,18 +436,27 @@ static int real_merge(struct merge_tree_options *o, merge_incore_recursive(&opt, merge_bases, parent1, parent2, &result); if (result.clean < 0) die(_("failure to merge")); + + if (o->show_messages == -1) + o->show_messages = !result.clean; + puts(oid_to_hex(&result.tree->object.oid)); + if (o->show_messages) { + printf("\n"); + merge_display_update_messages(&opt, &result); + } merge_finalize(&opt, &result); return !result.clean; /* result.clean < 0 handled above */ } int cmd_merge_tree(int argc, const char **argv, const char *prefix) { - struct merge_tree_options o = { 0 }; + struct merge_tree_options o = { .show_messages = -1 }; int expected_remaining_argc; + int original_argc; const char * const merge_tree_usage[] = { - N_("git merge-tree [--write-tree] "), + N_("git merge-tree [--write-tree] [] "), N_("git merge-tree [--trivial-merge] "), NULL }; @@ -456,10 +466,13 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) MODE_REAL), OPT_CMDMODE(0, "trivial-merge", &o.mode, N_("do a trivial merge only"), MODE_TRIVIAL), + OPT_BOOL(0, "messages", &o.show_messages, + N_("also show informational/conflict messages")), OPT_END() }; /* Parse arguments */ + original_argc = argc - 1; /* ignoring argv[0] */ argc = parse_options(argc, argv, prefix, mt_options, merge_tree_usage, PARSE_OPT_STOP_AT_NON_OPTION); switch (o.mode) { @@ -483,8 +496,12 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) break; case MODE_TRIVIAL: expected_remaining_argc = 3; + /* Removal of `--trivial-merge` is expected */ + original_argc--; break; } + if (o.mode == MODE_TRIVIAL && argc < original_argc) + die(_("--trivial-merge is incompatible with all other options")); if (argc != expected_remaining_argc) usage_with_options(merge_tree_usage, mt_options); diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh index 6d321652e2..719d81e717 100755 --- a/t/t4301-merge-tree-write-tree.sh +++ b/t/t4301-merge-tree-write-tree.sh @@ -103,4 +103,41 @@ test_expect_success 'Barf on too many arguments' ' grep "^usage: git merge-tree" expect ' +anonymize_hash() { + sed -e "s/[0-9a-f]\{40,\}/HASH/g" "$@" +} + +test_expect_success 'test conflict notices and such' ' + test_expect_code 1 git merge-tree --write-tree side1 side2 >out && + anonymize_hash out >actual && + + # Expected results: + # "greeting" should merge with conflicts + # "numbers" should merge cleanly + # "whatever" has *both* a modify/delete and a file/directory conflict + cat <<-EOF >expect && + HASH + + Auto-merging greeting + CONFLICT (content): Merge conflict in greeting + Auto-merging numbers + CONFLICT (file/directory): directory in the way of whatever from side1; moving it to whatever~side1 instead. + CONFLICT (modify/delete): whatever~side1 deleted in side2 and modified in side1. Version side1 of whatever~side1 left in tree. + EOF + + test_cmp expect actual +' + +for opt in $(git merge-tree --git-completion-helper-all) +do + if test $opt = "--trivial-merge" || test $opt = "--write-tree" + then + continue + fi + + test_expect_success "usage: --trivial-merge is incompatible with $opt" ' + test_expect_code 128 git merge-tree --trivial-merge $opt side1 side2 side3 + ' +done + test_done From fae26ce79cad6d290e296e40f2d46eb783e91110 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:50 +0000 Subject: [PATCH 07/17] merge-ort: provide a merge_get_conflicted_files() helper function After a merge, this function allows the user to extract the same information that would be printed by `ls-files -u`, which means files with their mode, oid, and stage. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- merge-ort.c | 31 +++++++++++++++++++++++++++++++ merge-ort.h | 21 +++++++++++++++++++++ 2 files changed, 52 insertions(+) diff --git a/merge-ort.c b/merge-ort.c index 3c6d0577de..bc1fcad8b4 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -4296,6 +4296,37 @@ void merge_display_update_messages(struct merge_options *opt, trace2_region_leave("merge", "display messages", opt->repo); } +void merge_get_conflicted_files(struct merge_result *result, + struct string_list *conflicted_files) +{ + struct hashmap_iter iter; + struct strmap_entry *e; + struct merge_options_internal *opti = result->priv; + + strmap_for_each_entry(&opti->conflicted, &iter, e) { + const char *path = e->key; + struct conflict_info *ci = e->value; + int i; + + VERIFY_CI(ci); + + for (i = MERGE_BASE; i <= MERGE_SIDE2; i++) { + struct stage_info *si; + + if (!(ci->filemask & (1ul << i))) + continue; + + si = xmalloc(sizeof(*si)); + si->stage = i+1; + si->mode = ci->stages[i].mode; + oidcpy(&si->oid, &ci->stages[i].oid); + string_list_append(conflicted_files, path)->util = si; + } + } + /* string_list_sort() uses a stable sort, so we're good */ + string_list_sort(conflicted_files); +} + void merge_switch_to_result(struct merge_options *opt, struct tree *head, struct merge_result *result, diff --git a/merge-ort.h b/merge-ort.h index e5aec45b18..ddcc39d727 100644 --- a/merge-ort.h +++ b/merge-ort.h @@ -2,6 +2,7 @@ #define MERGE_ORT_H #include "merge-recursive.h" +#include "hash.h" struct commit; struct tree; @@ -88,6 +89,26 @@ void merge_switch_to_result(struct merge_options *opt, void merge_display_update_messages(struct merge_options *opt, struct merge_result *result); +struct stage_info { + struct object_id oid; + int mode; + int stage; +}; + +/* + * Provide a list of path -> {struct stage_info*} mappings for + * all conflicted files. Note that each path could appear up to three + * times in the list, corresponding to 3 different stage entries. In short, + * this basically provides the info that would be printed by `ls-files -u`. + * + * result should have been populated by a call to + * one of the merge_incore_[non]recursive() functions. + * + * conflicted_files should be empty before calling this function. + */ +void merge_get_conflicted_files(struct merge_result *result, + struct string_list *conflicted_files); + /* Do needed cleanup when not calling merge_switch_to_result() */ void merge_finalize(struct merge_options *opt, struct merge_result *result); From a4040cfa35d8781df3e994380d1b559be8b22bd2 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:51 +0000 Subject: [PATCH 08/17] merge-ort: remove command-line-centric submodule message from merge-ort There was one case in merge-ort that would call path_msg() multiple times for the same logical conflict, and it was in order to give advice about how to resolve a conflict. This advice does not make as much sense with remerge-diff, or with merge-tree being invoked by a GitHub GUI for resolution of messages, and is making it hard to provide which-logical-conflict-affects-which-paths information in a machine parseable way to a higher level caller of merge-tree. Let's simply remove this informational message. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- merge-ort.c | 9 +-------- t/t6437-submodule-merge.sh | 2 +- 2 files changed, 2 insertions(+), 9 deletions(-) diff --git a/merge-ort.c b/merge-ort.c index bc1fcad8b4..3432efcacd 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -1694,15 +1694,8 @@ static int merge_submodule(struct merge_options *opt, (struct commit *)merges.objects[0].item); path_msg(opt, path, 0, _("Failed to merge submodule %s, but a possible merge " - "resolution exists:\n%s\n"), + "resolution exists: %s"), path, sb.buf); - path_msg(opt, path, 1, - _("If this is correct simply add it to the index " - "for example\n" - "by using:\n\n" - " git update-index --cacheinfo 160000 %s \"%s\"\n\n" - "which will accept this suggestion.\n"), - oid_to_hex(&merges.objects[0].item->oid), path); strbuf_release(&sb); break; default: diff --git a/t/t6437-submodule-merge.sh b/t/t6437-submodule-merge.sh index 178413c22f..c253bf759a 100755 --- a/t/t6437-submodule-merge.sh +++ b/t/t6437-submodule-merge.sh @@ -133,7 +133,7 @@ test_expect_success 'merging should conflict for non fast-forward' ' (cd merge-search && git checkout -b test-nonforward b && (cd sub && - git rev-parse sub-d > ../expect) && + git rev-parse --short sub-d > ../expect) && if test "$GIT_TEST_MERGE_ALGORITHM" = ort then test_must_fail git merge c >actual From 7fa3338870d66dd3946c5c3a0bd09dadb798893d Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:52 +0000 Subject: [PATCH 09/17] merge-tree: provide a list of which files have conflicts Callers of `git merge-tree --write-tree` will often want to know which files had conflicts. While they could potentially attempt to parse the CONFLICT notices printed, those messages are not meant to be machine readable. Provide a simpler mechanism of just printing the files (in the same format as `git ls-files` with quoting, but restricted to unmerged files) in the output before the free-form messages. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- Documentation/git-merge-tree.txt | 9 +++++++++ builtin/merge-tree.c | 26 +++++++++++++++++++++++--- t/t4301-merge-tree-write-tree.sh | 11 +++++++++++ 3 files changed, 43 insertions(+), 3 deletions(-) diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt index 25b462be14..68a51c8261 100644 --- a/Documentation/git-merge-tree.txt +++ b/Documentation/git-merge-tree.txt @@ -58,6 +58,7 @@ line: Whereas for a conflicted merge, the output is by default of the form: + These are discussed individually below. @@ -70,6 +71,14 @@ This is a tree object that represents what would be checked out in the working tree at the end of `git merge`. If there were conflicts, then files within this tree may have embedded conflict markers. +[[CFI]] +Conflicted file list +~~~~~~~~~~~~~~~~~~~~ + +This is a sequence of lines containing a filename on each line, quoted +as explained for the configuration variable `core.quotePath` (see +linkgit:git-config[1]). + [[IM]] Informational messages ~~~~~~~~~~~~~~~~~~~~~~ diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 831d9c7758..13a9536f7c 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -11,6 +11,9 @@ #include "blob.h" #include "exec-cmd.h" #include "merge-blobs.h" +#include "quote.h" + +static int line_termination = '\n'; struct merge_list { struct merge_list *next; @@ -400,7 +403,8 @@ struct merge_tree_options { }; static int real_merge(struct merge_tree_options *o, - const char *branch1, const char *branch2) + const char *branch1, const char *branch2, + const char *prefix) { struct commit *parent1, *parent2; struct commit_list *merge_bases = NULL; @@ -441,8 +445,24 @@ static int real_merge(struct merge_tree_options *o, o->show_messages = !result.clean; puts(oid_to_hex(&result.tree->object.oid)); + if (!result.clean) { + struct string_list conflicted_files = STRING_LIST_INIT_NODUP; + const char *last = NULL; + int i; + + merge_get_conflicted_files(&result, &conflicted_files); + for (i = 0; i < conflicted_files.nr; i++) { + const char *name = conflicted_files.items[i].string; + if (last && !strcmp(last, name)) + continue; + write_name_quoted_relative( + name, prefix, stdout, line_termination); + last = name; + } + string_list_clear(&conflicted_files, 1); + } if (o->show_messages) { - printf("\n"); + putchar(line_termination); merge_display_update_messages(&opt, &result); } merge_finalize(&opt, &result); @@ -508,7 +528,7 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) /* Do the relevant type of merge */ if (o.mode == MODE_REAL) - return real_merge(&o, argv[0], argv[1]); + return real_merge(&o, argv[0], argv[1], prefix); else return trivial_merge(argv[0], argv[1], argv[2]); } diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh index 719d81e717..8e6dba4428 100755 --- a/t/t4301-merge-tree-write-tree.sh +++ b/t/t4301-merge-tree-write-tree.sh @@ -117,6 +117,8 @@ test_expect_success 'test conflict notices and such' ' # "whatever" has *both* a modify/delete and a file/directory conflict cat <<-EOF >expect && HASH + greeting + whatever~side1 Auto-merging greeting CONFLICT (content): Merge conflict in greeting @@ -140,4 +142,13 @@ do ' done +test_expect_success 'Just the conflicted files without the messages' ' + test_expect_code 1 git merge-tree --write-tree --no-messages side1 side2 >out && + anonymize_hash out >actual && + + test_write_lines HASH greeting whatever~side1 >expect && + + test_cmp expect actual +' + test_done From b520bc6caa35e621396dd69ae4d84314615cf7ac Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:53 +0000 Subject: [PATCH 10/17] merge-tree: provide easy access to `ls-files -u` style info Much like `git merge` updates the index with information of the form (mode, oid, stage, name) provide this output for conflicted files for merge-tree as well. Provide a --name-only option for users to exclude the mode, oid, and stage and only get the list of conflicted filenames. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- Documentation/git-merge-tree.txt | 34 ++++++++++++++++++++++++++------ builtin/merge-tree.c | 11 ++++++++++- t/t4301-merge-tree-write-tree.sh | 26 ++++++++++++++++++++++-- 3 files changed, 62 insertions(+), 9 deletions(-) diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt index 68a51c8261..b89aabdb98 100644 --- a/Documentation/git-merge-tree.txt +++ b/Documentation/git-merge-tree.txt @@ -40,6 +40,13 @@ After the merge completes, a new toplevel tree object is created. See OPTIONS ------- +--name-only:: + In the Conflicted file info section, instead of writing a list + of (mode, oid, stage, path) tuples to output for conflicted + files, just provide a list of filenames with conflicts (and + do not list filenames multiple times if they have multiple + conflicting stages). + --[no-]messages:: Write any informational messages such as "Auto-merging " or CONFLICT notices to the end of stdout. If unspecified, the @@ -58,7 +65,7 @@ line: Whereas for a conflicted merge, the output is by default of the form: - + These are discussed individually below. @@ -72,19 +79,24 @@ working tree at the end of `git merge`. If there were conflicts, then files within this tree may have embedded conflict markers. [[CFI]] -Conflicted file list +Conflicted file info ~~~~~~~~~~~~~~~~~~~~ -This is a sequence of lines containing a filename on each line, quoted -as explained for the configuration variable `core.quotePath` (see -linkgit:git-config[1]). +This is a sequence of lines with the format + + + +The filename will be quoted as explained for the configuration +variable `core.quotePath` (see linkgit:git-config[1]). However, if +the `--name-only` option is passed, the mode, object, and stage will +be omitted. [[IM]] Informational messages ~~~~~~~~~~~~~~~~~~~~~~ This always starts with a blank line to separate it from the previous -section, and then has free-form messages about the merge, such as: +sections, and then has free-form messages about the merge, such as: * "Auto-merging " * "CONFLICT (rename/delete): renamed...but deleted in..." @@ -116,6 +128,16 @@ used as a part of a series of steps such as: Note that when the exit status is non-zero, `NEWTREE` in this sequence will contain a lot more output than just a tree. +For conflicts, the output includes the same information that you'd get +with linkgit:git-merge[1]: + + * what would be written to the working tree (the + <>) + * the higher order stages that would be written to the index (the + <>) + * any messages that would have been printed to stdout (the + <>) + [[DEPMERGE]] DEPRECATED DESCRIPTION ---------------------- diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index 13a9536f7c..c61b5b4a10 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -400,6 +400,7 @@ enum mode { struct merge_tree_options { int mode; int show_messages; + int name_only; }; static int real_merge(struct merge_tree_options *o, @@ -453,7 +454,11 @@ static int real_merge(struct merge_tree_options *o, merge_get_conflicted_files(&result, &conflicted_files); for (i = 0; i < conflicted_files.nr; i++) { const char *name = conflicted_files.items[i].string; - if (last && !strcmp(last, name)) + struct stage_info *c = conflicted_files.items[i].util; + if (!o->name_only) + printf("%06o %s %d\t", + c->mode, oid_to_hex(&c->oid), c->stage); + else if (last && !strcmp(last, name)) continue; write_name_quoted_relative( name, prefix, stdout, line_termination); @@ -488,6 +493,10 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) N_("do a trivial merge only"), MODE_TRIVIAL), OPT_BOOL(0, "messages", &o.show_messages, N_("also show informational/conflict messages")), + OPT_BOOL_F(0, "name-only", + &o.name_only, + N_("list filenames without modes/oids/stages"), + PARSE_OPT_NONEG), OPT_END() }; diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh index 8e6dba4428..0ec5f0d3f7 100755 --- a/t/t4301-merge-tree-write-tree.sh +++ b/t/t4301-merge-tree-write-tree.sh @@ -65,6 +65,7 @@ test_expect_success 'Content merge and a few conflicts' ' expected_tree=$(git rev-parse AUTO_MERGE) && # We will redo the merge, while we are still in a conflicted state! + git ls-files -u >conflicted-file-info && test_when_finished "git reset --hard" && test_expect_code 1 git merge-tree --write-tree side1 side2 >RESULT && @@ -108,7 +109,7 @@ anonymize_hash() { } test_expect_success 'test conflict notices and such' ' - test_expect_code 1 git merge-tree --write-tree side1 side2 >out && + test_expect_code 1 git merge-tree --write-tree --name-only side1 side2 >out && anonymize_hash out >actual && # Expected results: @@ -143,7 +144,7 @@ do done test_expect_success 'Just the conflicted files without the messages' ' - test_expect_code 1 git merge-tree --write-tree --no-messages side1 side2 >out && + test_expect_code 1 git merge-tree --write-tree --no-messages --name-only side1 side2 >out && anonymize_hash out >actual && test_write_lines HASH greeting whatever~side1 >expect && @@ -151,4 +152,25 @@ test_expect_success 'Just the conflicted files without the messages' ' test_cmp expect actual ' +test_expect_success 'Check conflicted oids and modes without messages' ' + test_expect_code 1 git merge-tree --write-tree --no-messages side1 side2 >out && + anonymize_hash out >actual && + + # Compare the basic output format + q_to_tab >expect <<-\EOF && + HASH + 100644 HASH 1Qgreeting + 100644 HASH 2Qgreeting + 100644 HASH 3Qgreeting + 100644 HASH 1Qwhatever~side1 + 100644 HASH 2Qwhatever~side1 + EOF + + test_cmp expect actual && + + # Check the actual hashes against the `ls-files -u` output too + tail -n +2 out | sed -e s/side1/HEAD/ >actual && + test_cmp conflicted-file-info actual +' + test_done From 6debb7527b0e2f791256a216394503899b0488ee Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Sat, 18 Jun 2022 00:20:54 +0000 Subject: [PATCH 11/17] merge-ort: store messages in a list, not in a single strbuf To prepare for using the `merge-ort` machinery in server operations, we cannot simply produce a free-form string that combines a variable-length list of messages. Instead, we need to list them one by one. The natural fit for this is a `string_list`. We will subsequently add even more information in the `util` attribute of the string list items. Based-on-a-patch-by: Elijah Newren Signed-off-by: Johannes Schindelin Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- merge-ort.c | 123 ++++++++++++++++++++++++++++++++++------------------ merge-ort.h | 2 +- 2 files changed, 81 insertions(+), 44 deletions(-) diff --git a/merge-ort.c b/merge-ort.c index 3432efcacd..9e9f2fc674 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -349,13 +349,15 @@ struct merge_options_internal { struct mem_pool pool; /* - * output: special messages and conflict notices for various paths + * conflicts: logical conflicts and messages stored by _primary_ path * * This is a map of pathnames (a subset of the keys in "paths" above) - * to strbufs. It gathers various warning/conflict/notice messages - * for later processing. + * to struct string_list, with each item's `util` containing a + * `struct logical_conflict_info`. Note, though, that for each path, + * it only stores the logical conflicts for which that path is the + * primary path; the path might be part of additional conflicts. */ - struct strmap output; + struct strmap conflicts; /* * renames: various data relating to rename detection @@ -567,20 +569,20 @@ static void clear_or_reinit_internal_opts(struct merge_options_internal *opti, struct strmap_entry *e; /* Release and free each strbuf found in output */ - strmap_for_each_entry(&opti->output, &iter, e) { - struct strbuf *sb = e->value; - strbuf_release(sb); + strmap_for_each_entry(&opti->conflicts, &iter, e) { + struct string_list *list = e->value; /* - * While strictly speaking we don't need to free(sb) - * here because we could pass free_values=1 when - * calling strmap_clear() on opti->output, that would - * require strmap_clear to do another - * strmap_for_each_entry() loop, so we just free it - * while we're iterating anyway. + * While strictly speaking we don't need to + * free(conflicts) here because we could pass + * free_values=1 when calling strmap_clear() on + * opti->conflicts, that would require strmap_clear + * to do another strmap_for_each_entry() loop, so we + * just free it while we're iterating anyway. */ - free(sb); + string_list_clear(list, 1); + free(list); } - strmap_clear(&opti->output, 0); + strmap_clear(&opti->conflicts, 0); } mem_pool_discard(&opti->pool, 0); @@ -634,7 +636,9 @@ static void path_msg(struct merge_options *opt, const char *fmt, ...) { va_list ap; - struct strbuf *sb, *dest; + struct string_list *path_conflicts; + struct strbuf buf = STRBUF_INIT; + struct strbuf *dest; struct strbuf tmp = STRBUF_INIT; if (opt->record_conflict_msgs_as_headers && omittable_hint) @@ -642,14 +646,16 @@ static void path_msg(struct merge_options *opt, if (opt->priv->call_depth && opt->verbosity < 5) return; /* Ignore messages from inner merges */ - sb = strmap_get(&opt->priv->output, path); - if (!sb) { - sb = xmalloc(sizeof(*sb)); - strbuf_init(sb, 0); - strmap_put(&opt->priv->output, path, sb); + /* Ensure path_conflicts (ptr to array of logical_conflict) allocated */ + path_conflicts = strmap_get(&opt->priv->conflicts, path); + if (!path_conflicts) { + path_conflicts = xmalloc(sizeof(*path_conflicts)); + string_list_init_dup(path_conflicts); + strmap_put(&opt->priv->conflicts, path, path_conflicts); } - dest = (opt->record_conflict_msgs_as_headers ? &tmp : sb); + /* Handle message and its format, in normal case */ + dest = (opt->record_conflict_msgs_as_headers ? &tmp : &buf); va_start(ap, fmt); if (opt->priv->call_depth) { @@ -660,32 +666,31 @@ static void path_msg(struct merge_options *opt, strbuf_vaddf(dest, fmt, ap); va_end(ap); + /* Handle specialized formatting of message under --remerge-diff */ if (opt->record_conflict_msgs_as_headers) { int i_sb = 0, i_tmp = 0; /* Start with the specified prefix */ if (opt->msg_header_prefix) - strbuf_addf(sb, "%s ", opt->msg_header_prefix); + strbuf_addf(&buf, "%s ", opt->msg_header_prefix); /* Copy tmp to sb, adding spaces after newlines */ - strbuf_grow(sb, sb->len + 2*tmp.len); /* more than sufficient */ + strbuf_grow(&buf, buf.len + 2*tmp.len); /* more than sufficient */ for (; i_tmp < tmp.len; i_tmp++, i_sb++) { /* Copy next character from tmp to sb */ - sb->buf[sb->len + i_sb] = tmp.buf[i_tmp]; + buf.buf[buf.len + i_sb] = tmp.buf[i_tmp]; /* If we copied a newline, add a space */ if (tmp.buf[i_tmp] == '\n') - sb->buf[++i_sb] = ' '; + buf.buf[++i_sb] = ' '; } /* Update length and ensure it's NUL-terminated */ - sb->len += i_sb; - sb->buf[sb->len] = '\0'; + buf.len += i_sb; + buf.buf[buf.len] = '\0'; strbuf_release(&tmp); } - - /* Add final newline character to sb */ - strbuf_addch(sb, '\n'); + string_list_append_nodup(path_conflicts, strbuf_detach(&buf, NULL)); } static struct diff_filespec *pool_alloc_filespec(struct mem_pool *pool, @@ -4257,7 +4262,6 @@ void merge_display_update_messages(struct merge_options *opt, struct hashmap_iter iter; struct strmap_entry *e; struct string_list olist = STRING_LIST_INIT_NODUP; - int i; if (opt->record_conflict_msgs_as_headers) BUG("Either display conflict messages or record them as headers, not both"); @@ -4265,20 +4269,20 @@ void merge_display_update_messages(struct merge_options *opt, trace2_region_enter("merge", "display messages", opt->repo); /* Hack to pre-allocate olist to the desired size */ - ALLOC_GROW(olist.items, strmap_get_size(&opti->output), + ALLOC_GROW(olist.items, strmap_get_size(&opti->conflicts), olist.alloc); /* Put every entry from output into olist, then sort */ - strmap_for_each_entry(&opti->output, &iter, e) { + strmap_for_each_entry(&opti->conflicts, &iter, e) { string_list_append(&olist, e->key)->util = e->value; } string_list_sort(&olist); /* Iterate over the items, printing them */ - for (i = 0; i < olist.nr; ++i) { - struct strbuf *sb = olist.items[i].util; - - printf("%s", sb->buf); + for (int path_nr = 0; path_nr < olist.nr; ++path_nr) { + struct string_list *conflicts = olist.items[path_nr].util; + for (int i = 0; i < conflicts->nr; i++) + puts(conflicts->items[i].string); } string_list_clear(&olist, 0); @@ -4367,6 +4371,8 @@ void merge_finalize(struct merge_options *opt, struct merge_result *result) { struct merge_options_internal *opti = result->priv; + struct hashmap_iter iter; + struct strmap_entry *e; if (opt->renormalize) git_attr_set_direction(GIT_ATTR_CHECKIN); @@ -4374,6 +4380,15 @@ void merge_finalize(struct merge_options *opt, clear_or_reinit_internal_opts(opti, 0); FREE_AND_NULL(opti); + + /* Release and free each strbuf found in path_messages */ + strmap_for_each_entry(result->path_messages, &iter, e) { + struct strbuf *buf = e->value; + + strbuf_release(buf); + } + strmap_clear(result->path_messages, 1); + FREE_AND_NULL(result->path_messages); } /*** Function Grouping: helper functions for merge_incore_*() ***/ @@ -4532,11 +4547,11 @@ static void merge_start(struct merge_options *opt, struct merge_result *result) strmap_init_with_options(&opt->priv->conflicted, pool, 0); /* - * keys & strbufs in output will sometimes need to outlive "paths", - * so it will have a copy of relevant keys. It's probably a small - * subset of the overall paths that have special output. + * keys & string_lists in conflicts will sometimes need to outlive + * "paths", so it will have a copy of relevant keys. It's probably + * a small subset of the overall paths that have special output. */ - strmap_init(&opt->priv->output); + strmap_init(&opt->priv->conflicts); trace2_region_leave("merge", "allocate/init", opt->repo); } @@ -4597,6 +4612,8 @@ static void merge_ort_nonrecursive_internal(struct merge_options *opt, struct merge_result *result) { struct object_id working_tree_oid; + struct hashmap_iter iter; + struct strmap_entry *e; if (opt->subtree_shift) { side2 = shift_tree_object(opt->repo, side1, side2, @@ -4637,7 +4654,27 @@ redo: trace2_region_leave("merge", "process_entries", opt->repo); /* Set return values */ - result->path_messages = &opt->priv->output; + result->path_messages = xcalloc(1, sizeof(*result->path_messages)); + strmap_init_with_options(result->path_messages, NULL, 0); + strmap_for_each_entry(&opt->priv->conflicts, &iter, e) { + const char *path = e->key; + struct strbuf *buf = strmap_get(result->path_messages, path); + struct string_list *conflicts = e->value; + + if (!buf) { + buf = xcalloc(1, sizeof(*buf)); + strbuf_init(buf, 0); + strmap_put(result->path_messages, path, buf); + } + + for (int i = 0; i < conflicts->nr; i++) { + if (buf->len) + strbuf_addch(buf, '\n'); + strbuf_addstr(buf, conflicts->items[i].string); + strbuf_trim_trailing_newline(buf); + } + } + result->tree = parse_tree_indirect(&working_tree_oid); /* existence of conflicted entries implies unclean */ result->clean &= strmap_empty(&opt->priv->conflicted); diff --git a/merge-ort.h b/merge-ort.h index ddcc39d727..f9c536ed8c 100644 --- a/merge-ort.h +++ b/merge-ort.h @@ -28,7 +28,7 @@ struct merge_result { /* * Special messages and conflict notices for various paths * - * This is a map of pathnames to strbufs. It contains various + * This is a map of pathnames to strbufs. It contains various * warning/conflict/notice messages (possibly multiple per path) * that callers may want to use. */ From 2715e8a931ce1ad3a7bcffbdc6c0e556ae87d158 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Sat, 18 Jun 2022 00:20:55 +0000 Subject: [PATCH 12/17] merge-ort: make `path_messages` a strmap to a string_list This allows us once again to get away with less data copying. Signed-off-by: Johannes Schindelin Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- diff.c | 27 ++++++++++++++++++++------- merge-ort.c | 34 +--------------------------------- merge-ort.h | 2 +- 3 files changed, 22 insertions(+), 41 deletions(-) diff --git a/diff.c b/diff.c index e71cf75886..2214ae49e4 100644 --- a/diff.c +++ b/diff.c @@ -3362,23 +3362,23 @@ struct userdiff_driver *get_textconv(struct repository *r, return userdiff_get_textconv(r, one->driver); } -static struct strbuf *additional_headers(struct diff_options *o, - const char *path) +static struct string_list *additional_headers(struct diff_options *o, + const char *path) { if (!o->additional_path_headers) return NULL; return strmap_get(o->additional_path_headers, path); } -static void add_formatted_headers(struct strbuf *msg, - struct strbuf *more_headers, +static void add_formatted_header(struct strbuf *msg, + const char *header, const char *line_prefix, const char *meta, const char *reset) { - char *next, *newline; + const char *next, *newline; - for (next = more_headers->buf; *next; next = newline) { + for (next = header; *next; next = newline) { newline = strchrnul(next, '\n'); strbuf_addf(msg, "%s%s%.*s%s\n", line_prefix, meta, (int)(newline - next), next, reset); @@ -3387,6 +3387,19 @@ static void add_formatted_headers(struct strbuf *msg, } } +static void add_formatted_headers(struct strbuf *msg, + struct string_list *more_headers, + const char *line_prefix, + const char *meta, + const char *reset) +{ + int i; + + for (i = 0; i < more_headers->nr; i++) + add_formatted_header(msg, more_headers->items[i].string, + line_prefix, meta, reset); +} + static void builtin_diff(const char *name_a, const char *name_b, struct diff_filespec *one, @@ -4314,7 +4327,7 @@ static void fill_metainfo(struct strbuf *msg, const char *set = diff_get_color(use_color, DIFF_METAINFO); const char *reset = diff_get_color(use_color, DIFF_RESET); const char *line_prefix = diff_line_prefix(o); - struct strbuf *more_headers = NULL; + struct string_list *more_headers = NULL; *must_show_header = 1; strbuf_init(msg, PATH_MAX * 2 + 300); diff --git a/merge-ort.c b/merge-ort.c index 9e9f2fc674..f31c7029ce 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -4371,8 +4371,6 @@ void merge_finalize(struct merge_options *opt, struct merge_result *result) { struct merge_options_internal *opti = result->priv; - struct hashmap_iter iter; - struct strmap_entry *e; if (opt->renormalize) git_attr_set_direction(GIT_ATTR_CHECKIN); @@ -4380,15 +4378,6 @@ void merge_finalize(struct merge_options *opt, clear_or_reinit_internal_opts(opti, 0); FREE_AND_NULL(opti); - - /* Release and free each strbuf found in path_messages */ - strmap_for_each_entry(result->path_messages, &iter, e) { - struct strbuf *buf = e->value; - - strbuf_release(buf); - } - strmap_clear(result->path_messages, 1); - FREE_AND_NULL(result->path_messages); } /*** Function Grouping: helper functions for merge_incore_*() ***/ @@ -4612,8 +4601,6 @@ static void merge_ort_nonrecursive_internal(struct merge_options *opt, struct merge_result *result) { struct object_id working_tree_oid; - struct hashmap_iter iter; - struct strmap_entry *e; if (opt->subtree_shift) { side2 = shift_tree_object(opt->repo, side1, side2, @@ -4654,26 +4641,7 @@ redo: trace2_region_leave("merge", "process_entries", opt->repo); /* Set return values */ - result->path_messages = xcalloc(1, sizeof(*result->path_messages)); - strmap_init_with_options(result->path_messages, NULL, 0); - strmap_for_each_entry(&opt->priv->conflicts, &iter, e) { - const char *path = e->key; - struct strbuf *buf = strmap_get(result->path_messages, path); - struct string_list *conflicts = e->value; - - if (!buf) { - buf = xcalloc(1, sizeof(*buf)); - strbuf_init(buf, 0); - strmap_put(result->path_messages, path, buf); - } - - for (int i = 0; i < conflicts->nr; i++) { - if (buf->len) - strbuf_addch(buf, '\n'); - strbuf_addstr(buf, conflicts->items[i].string); - strbuf_trim_trailing_newline(buf); - } - } + result->path_messages = &opt->priv->conflicts; result->tree = parse_tree_indirect(&working_tree_oid); /* existence of conflicted entries implies unclean */ diff --git a/merge-ort.h b/merge-ort.h index f9c536ed8c..c4909bcbf9 100644 --- a/merge-ort.h +++ b/merge-ort.h @@ -28,7 +28,7 @@ struct merge_result { /* * Special messages and conflict notices for various paths * - * This is a map of pathnames to strbufs. It contains various + * This is a map of pathnames to a string_list. It contains various * warning/conflict/notice messages (possibly multiple per path) * that callers may want to use. */ From cb2607759e27627aca614726dc50e98ac0ba6d19 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:56 +0000 Subject: [PATCH 13/17] merge-ort: store more specific conflict information It is all fine and dandy for a regular Git command that is intended to be run interactively to produce a bunch of messages upon an error. However, in `merge-ort`'s case, we want to call the command e.g. in server-side software, where the actual error messages are not quite as interesting as machine-readable, immutable terms that describe the exact nature of any given conflict. With this patch, the `merge-ort` machinery records the exact type (as specified via an `enum` value) as well as the involved path(s) together with the conflict's message. Signed-off-by: Elijah Newren Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- merge-ort.c | 267 +++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 212 insertions(+), 55 deletions(-) diff --git a/merge-ort.c b/merge-ort.c index f31c7029ce..6081b29705 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -483,6 +483,100 @@ struct conflict_info { unsigned match_mask:3; }; +enum conflict_and_info_types { + /* "Simple" conflicts and informational messages */ + INFO_AUTO_MERGING = 0, + CONFLICT_CONTENTS, /* text file that failed to merge */ + CONFLICT_BINARY, + CONFLICT_FILE_DIRECTORY, + CONFLICT_DISTINCT_MODES, + CONFLICT_MODIFY_DELETE, + CONFLICT_PRESENT_DESPITE_SKIPPED, + + /* Regular rename */ + CONFLICT_RENAME_RENAME, /* same file renamed differently */ + CONFLICT_RENAME_COLLIDES, /* rename/add or two files renamed to 1 */ + CONFLICT_RENAME_DELETE, + + /* Basic directory rename */ + CONFLICT_DIR_RENAME_SUGGESTED, + INFO_DIR_RENAME_APPLIED, + + /* Special directory rename cases */ + INFO_DIR_RENAME_SKIPPED_DUE_TO_RERENAME, + CONFLICT_DIR_RENAME_FILE_IN_WAY, + CONFLICT_DIR_RENAME_COLLISION, + CONFLICT_DIR_RENAME_SPLIT, + + /* Basic submodule */ + INFO_SUBMODULE_FAST_FORWARDING, + CONFLICT_SUBMODULE_FAILED_TO_MERGE, + + /* Special submodule cases broken out from FAILED_TO_MERGE */ + CONFLICT_SUBMODULE_FAILED_TO_MERGE_BUT_POSSIBLE_RESOLUTION, + CONFLICT_SUBMODULE_NOT_INITIALIZED, + CONFLICT_SUBMODULE_HISTORY_NOT_AVAILABLE, + CONFLICT_SUBMODULE_MAY_HAVE_REWINDS, + + /* Keep this entry _last_ in the list */ + NB_CONFLICT_TYPES, +}; + +/* + * Short description of conflict type, relied upon by external tools. + * + * We can add more entries, but DO NOT change any of these strings. Also, + * Order MUST match conflict_info_and_types. + */ +static const char *type_short_descriptions[] = { + /*** "Simple" conflicts and informational messages ***/ + [INFO_AUTO_MERGING] = "Auto-merging", + [CONFLICT_CONTENTS] = "CONFLICT (contents)", + [CONFLICT_BINARY] = "CONFLICT (binary)", + [CONFLICT_FILE_DIRECTORY] = "CONFLICT (file/directory)", + [CONFLICT_DISTINCT_MODES] = "CONFLICT (distinct modes)", + [CONFLICT_MODIFY_DELETE] = "CONFLICT (modify/delete)", + [CONFLICT_PRESENT_DESPITE_SKIPPED] = + "CONFLICT (upgrade your version of git)", + + /*** Regular rename ***/ + [CONFLICT_RENAME_RENAME] = "CONFLICT (rename/rename)", + [CONFLICT_RENAME_COLLIDES] = "CONFLICT (rename involved in collision)", + [CONFLICT_RENAME_DELETE] = "CONFLICT (rename/delete)", + + /*** Basic directory rename ***/ + [CONFLICT_DIR_RENAME_SUGGESTED] = + "CONFLICT (directory rename suggested)", + [INFO_DIR_RENAME_APPLIED] = "Path updated due to directory rename", + + /*** Special directory rename cases ***/ + [INFO_DIR_RENAME_SKIPPED_DUE_TO_RERENAME] = + "Directory rename skipped since directory was renamed on both sides", + [CONFLICT_DIR_RENAME_FILE_IN_WAY] = + "CONFLICT (file in way of directory rename)", + [CONFLICT_DIR_RENAME_COLLISION] = "CONFLICT(directory rename collision)", + [CONFLICT_DIR_RENAME_SPLIT] = "CONFLICT(directory rename unclear split)", + + /*** Basic submodule ***/ + [INFO_SUBMODULE_FAST_FORWARDING] = "Fast forwarding submodule", + [CONFLICT_SUBMODULE_FAILED_TO_MERGE] = "CONFLICT (submodule)", + + /*** Special submodule cases broken out from FAILED_TO_MERGE ***/ + [CONFLICT_SUBMODULE_FAILED_TO_MERGE_BUT_POSSIBLE_RESOLUTION] = + "CONFLICT (submodule with possible resolution)", + [CONFLICT_SUBMODULE_NOT_INITIALIZED] = + "CONFLICT (submodule not initialized)", + [CONFLICT_SUBMODULE_HISTORY_NOT_AVAILABLE] = + "CONFLICT (submodule history not available)", + [CONFLICT_SUBMODULE_MAY_HAVE_REWINDS] = + "CONFLICT (submodule may have rewinds)", +}; + +struct logical_conflict_info { + enum conflict_and_info_types type; + struct strvec paths; +}; + /*** Function Grouping: various utility functions ***/ /* @@ -571,6 +665,11 @@ static void clear_or_reinit_internal_opts(struct merge_options_internal *opti, /* Release and free each strbuf found in output */ strmap_for_each_entry(&opti->conflicts, &iter, e) { struct string_list *list = e->value; + for (int i = 0; i < list->nr; i++) { + struct logical_conflict_info *info = + list->items[i].util; + strvec_clear(&info->paths); + } /* * While strictly speaking we don't need to * free(conflicts) here because we could pass @@ -629,31 +728,56 @@ static void format_commit(struct strbuf *sb, strbuf_addch(sb, '\n'); } -__attribute__((format (printf, 4, 5))) +__attribute__((format (printf, 8, 9))) static void path_msg(struct merge_options *opt, - const char *path, + enum conflict_and_info_types type, int omittable_hint, /* skippable under --remerge-diff */ + const char *primary_path, + const char *other_path_1, /* may be NULL */ + const char *other_path_2, /* may be NULL */ + struct string_list *other_paths, /* may be NULL */ const char *fmt, ...) { va_list ap; struct string_list *path_conflicts; + struct logical_conflict_info *info; struct strbuf buf = STRBUF_INIT; struct strbuf *dest; struct strbuf tmp = STRBUF_INIT; + /* Sanity checks */ + assert(omittable_hint == + !starts_with(type_short_descriptions[type], "CONFLICT") || + type == CONFLICT_DIR_RENAME_SUGGESTED || + type == CONFLICT_PRESENT_DESPITE_SKIPPED); if (opt->record_conflict_msgs_as_headers && omittable_hint) return; /* Do not record mere hints in headers */ if (opt->priv->call_depth && opt->verbosity < 5) return; /* Ignore messages from inner merges */ /* Ensure path_conflicts (ptr to array of logical_conflict) allocated */ - path_conflicts = strmap_get(&opt->priv->conflicts, path); + path_conflicts = strmap_get(&opt->priv->conflicts, primary_path); if (!path_conflicts) { path_conflicts = xmalloc(sizeof(*path_conflicts)); string_list_init_dup(path_conflicts); - strmap_put(&opt->priv->conflicts, path, path_conflicts); + strmap_put(&opt->priv->conflicts, primary_path, path_conflicts); } + /* Add a logical_conflict at the end to store info from this call */ + info = xcalloc(1, sizeof(*info)); + info->type = type; + strvec_init(&info->paths); + + /* Handle the list of paths */ + strvec_push(&info->paths, primary_path); + if (other_path_1) + strvec_push(&info->paths, other_path_1); + if (other_path_2) + strvec_push(&info->paths, other_path_2); + if (other_paths) + for (int i = 0; i < other_paths->nr; i++) + strvec_push(&info->paths, other_paths->items[i].string); + /* Handle message and its format, in normal case */ dest = (opt->record_conflict_msgs_as_headers ? &tmp : &buf); @@ -690,7 +814,8 @@ static void path_msg(struct merge_options *opt, strbuf_release(&tmp); } - string_list_append_nodup(path_conflicts, strbuf_detach(&buf, NULL)); + string_list_append_nodup(path_conflicts, strbuf_detach(&buf, NULL)) + ->util = info; } static struct diff_filespec *pool_alloc_filespec(struct mem_pool *pool, @@ -1632,16 +1757,18 @@ static int merge_submodule(struct merge_options *opt, return 0; if (repo_submodule_init(&subrepo, opt->repo, path, null_oid())) { - path_msg(opt, path, 0, - _("Failed to merge submodule %s (not checked out)"), - path); + path_msg(opt, CONFLICT_SUBMODULE_NOT_INITIALIZED, 0, + path, NULL, NULL, NULL, + _("Failed to merge submodule %s (not checked out)"), + path); return 0; } if (!(commit_o = lookup_commit_reference(&subrepo, o)) || !(commit_a = lookup_commit_reference(&subrepo, a)) || !(commit_b = lookup_commit_reference(&subrepo, b))) { - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_SUBMODULE_HISTORY_NOT_AVAILABLE, 0, + path, NULL, NULL, NULL, _("Failed to merge submodule %s (commits not present)"), path); goto cleanup; @@ -1650,7 +1777,8 @@ static int merge_submodule(struct merge_options *opt, /* check whether both changes are forward */ if (!repo_in_merge_bases(&subrepo, commit_o, commit_a) || !repo_in_merge_bases(&subrepo, commit_o, commit_b)) { - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_SUBMODULE_MAY_HAVE_REWINDS, 0, + path, NULL, NULL, NULL, _("Failed to merge submodule %s " "(commits don't follow merge-base)"), path); @@ -1660,7 +1788,8 @@ static int merge_submodule(struct merge_options *opt, /* Case #1: a is contained in b or vice versa */ if (repo_in_merge_bases(&subrepo, commit_a, commit_b)) { oidcpy(result, b); - path_msg(opt, path, 1, + path_msg(opt, INFO_SUBMODULE_FAST_FORWARDING, 1, + path, NULL, NULL, NULL, _("Note: Fast-forwarding submodule %s to %s"), path, oid_to_hex(b)); ret = 1; @@ -1668,7 +1797,8 @@ static int merge_submodule(struct merge_options *opt, } if (repo_in_merge_bases(&subrepo, commit_b, commit_a)) { oidcpy(result, a); - path_msg(opt, path, 1, + path_msg(opt, INFO_SUBMODULE_FAST_FORWARDING, 1, + path, NULL, NULL, NULL, _("Note: Fast-forwarding submodule %s to %s"), path, oid_to_hex(a)); ret = 1; @@ -1691,13 +1821,16 @@ static int merge_submodule(struct merge_options *opt, &merges); switch (parent_count) { case 0: - path_msg(opt, path, 0, _("Failed to merge submodule %s"), path); + path_msg(opt, CONFLICT_SUBMODULE_FAILED_TO_MERGE, 0, + path, NULL, NULL, NULL, + _("Failed to merge submodule %s"), path); break; case 1: format_commit(&sb, 4, &subrepo, (struct commit *)merges.objects[0].item); - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_SUBMODULE_FAILED_TO_MERGE_BUT_POSSIBLE_RESOLUTION, 0, + path, NULL, NULL, NULL, _("Failed to merge submodule %s, but a possible merge " "resolution exists: %s"), path, sb.buf); @@ -1707,7 +1840,8 @@ static int merge_submodule(struct merge_options *opt, for (i = 0; i < merges.nr; i++) format_commit(&sb, 4, &subrepo, (struct commit *)merges.objects[i].item); - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_SUBMODULE_FAILED_TO_MERGE_BUT_POSSIBLE_RESOLUTION, 0, + path, NULL, NULL, NULL, _("Failed to merge submodule %s, but multiple " "possible merges exist:\n%s"), path, sb.buf); strbuf_release(&sb); @@ -1833,7 +1967,8 @@ static int merge_3way(struct merge_options *opt, &src1, name1, &src2, name2, &opt->priv->attr_index, &ll_opts); if (merge_status == LL_MERGE_BINARY_CONFLICT) - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_BINARY, 0, + path, NULL, NULL, NULL, "warning: Cannot merge binary files: %s (%s vs. %s)", path, name1, name2); @@ -1945,7 +2080,8 @@ static int handle_content_merge(struct merge_options *opt, if (ret) return -1; clean &= (merge_status == 0); - path_msg(opt, path, 1, _("Auto-merging %s"), path); + path_msg(opt, INFO_AUTO_MERGING, 1, path, NULL, NULL, NULL, + _("Auto-merging %s"), path); } else if (S_ISGITLINK(a->mode)) { int two_way = ((S_IFMT & o->mode) != (S_IFMT & a->mode)); clean = merge_submodule(opt, pathnames[0], @@ -2083,21 +2219,24 @@ static char *handle_path_level_conflicts(struct merge_options *opt, c_info->reported_already = 1; strbuf_add_separated_string_list(&collision_paths, ", ", &c_info->source_files); - path_msg(opt, new_path, 0, - _("CONFLICT (implicit dir rename): Existing file/dir " - "at %s in the way of implicit directory rename(s) " - "putting the following path(s) there: %s."), - new_path, collision_paths.buf); + path_msg(opt, CONFLICT_DIR_RENAME_FILE_IN_WAY, 0, + new_path, NULL, NULL, &c_info->source_files, + _("CONFLICT (implicit dir rename): Existing " + "file/dir at %s in the way of implicit " + "directory rename(s) putting the following " + "path(s) there: %s."), + new_path, collision_paths.buf); clean = 0; } else if (c_info->source_files.nr > 1) { c_info->reported_already = 1; strbuf_add_separated_string_list(&collision_paths, ", ", &c_info->source_files); - path_msg(opt, new_path, 0, - _("CONFLICT (implicit dir rename): Cannot map more " - "than one path to %s; implicit directory renames " - "tried to put these paths there: %s"), - new_path, collision_paths.buf); + path_msg(opt, CONFLICT_DIR_RENAME_COLLISION, 0, + new_path, NULL, NULL, &c_info->source_files, + _("CONFLICT (implicit dir rename): Cannot map " + "more than one path to %s; implicit directory " + "renames tried to put these paths there: %s"), + new_path, collision_paths.buf); clean = 0; } @@ -2151,13 +2290,14 @@ static void get_provisional_directory_renames(struct merge_options *opt, continue; if (bad_max == max) { - path_msg(opt, source_dir, 0, - _("CONFLICT (directory rename split): " - "Unclear where to rename %s to; it was " - "renamed to multiple other directories, with " - "no destination getting a majority of the " - "files."), - source_dir); + path_msg(opt, CONFLICT_DIR_RENAME_SPLIT, 0, + source_dir, NULL, NULL, NULL, + _("CONFLICT (directory rename split): " + "Unclear where to rename %s to; it was " + "renamed to multiple other directories, " + "with no destination getting a majority of " + "the files."), + source_dir); *clean = 0; } else { strmap_put(&renames->dir_renames[side], @@ -2305,7 +2445,8 @@ static char *check_for_directory_rename(struct merge_options *opt, */ otherinfo = strmap_get_entry(dir_rename_exclusions, new_dir); if (otherinfo) { - path_msg(opt, rename_info->key, 1, + path_msg(opt, INFO_DIR_RENAME_SKIPPED_DUE_TO_RERENAME, 1, + rename_info->key, path, new_dir, NULL, _("WARNING: Avoiding applying %s -> %s rename " "to %s, because %s itself was renamed."), rename_info->key, new_dir, path, new_dir); @@ -2445,14 +2586,16 @@ static void apply_directory_rename_modifications(struct merge_options *opt, if (opt->detect_directory_renames == MERGE_DIRECTORY_RENAMES_TRUE) { /* Notify user of updated path */ if (pair->status == 'A') - path_msg(opt, new_path, 1, + path_msg(opt, INFO_DIR_RENAME_APPLIED, 1, + new_path, old_path, NULL, NULL, _("Path updated: %s added in %s inside a " "directory that was renamed in %s; moving " "it to %s."), old_path, branch_with_new_path, branch_with_dir_rename, new_path); else - path_msg(opt, new_path, 1, + path_msg(opt, INFO_DIR_RENAME_APPLIED, 1, + new_path, old_path, NULL, NULL, _("Path updated: %s renamed to %s in %s, " "inside a directory that was renamed in %s; " "moving it to %s."), @@ -2465,7 +2608,8 @@ static void apply_directory_rename_modifications(struct merge_options *opt, */ ci->path_conflict = 1; if (pair->status == 'A') - path_msg(opt, new_path, 1, + path_msg(opt, CONFLICT_DIR_RENAME_SUGGESTED, 1, + new_path, old_path, NULL, NULL, _("CONFLICT (file location): %s added in %s " "inside a directory that was renamed in %s, " "suggesting it should perhaps be moved to " @@ -2473,7 +2617,8 @@ static void apply_directory_rename_modifications(struct merge_options *opt, old_path, branch_with_new_path, branch_with_dir_rename, new_path); else - path_msg(opt, new_path, 1, + path_msg(opt, CONFLICT_DIR_RENAME_SUGGESTED, 1, + new_path, old_path, NULL, NULL, _("CONFLICT (file location): %s renamed to %s " "in %s, inside a directory that was renamed " "in %s, suggesting it should perhaps be " @@ -2629,7 +2774,8 @@ static int process_renames(struct merge_options *opt, * and remove the setting of base->path_conflict to 1. */ base->path_conflict = 1; - path_msg(opt, oldpath, 0, + path_msg(opt, CONFLICT_RENAME_RENAME, 0, + pathnames[0], pathnames[1], pathnames[2], NULL, _("CONFLICT (rename/rename): %s renamed to " "%s in %s and to %s in %s."), pathnames[0], @@ -2724,7 +2870,8 @@ static int process_renames(struct merge_options *opt, memcpy(&newinfo->stages[target_index], &merged, sizeof(merged)); if (!clean) { - path_msg(opt, newpath, 0, + path_msg(opt, CONFLICT_RENAME_COLLIDES, 0, + newpath, oldpath, NULL, NULL, _("CONFLICT (rename involved in " "collision): rename of %s -> %s has " "content conflicts AND collides " @@ -2743,7 +2890,8 @@ static int process_renames(struct merge_options *opt, */ newinfo->path_conflict = 1; - path_msg(opt, newpath, 0, + path_msg(opt, CONFLICT_RENAME_DELETE, 0, + newpath, oldpath, NULL, NULL, _("CONFLICT (rename/delete): %s renamed " "to %s in %s, but deleted in %s."), oldpath, newpath, rename_branch, delete_branch); @@ -2767,7 +2915,8 @@ static int process_renames(struct merge_options *opt, } else if (source_deleted) { /* rename/delete */ newinfo->path_conflict = 1; - path_msg(opt, newpath, 0, + path_msg(opt, CONFLICT_RENAME_DELETE, 0, + newpath, oldpath, NULL, NULL, _("CONFLICT (rename/delete): %s renamed" " to %s in %s, but deleted in %s."), oldpath, newpath, @@ -3688,7 +3837,8 @@ static void process_entry(struct merge_options *opt, path = unique_path(opt, path, branch); strmap_put(&opt->priv->paths, path, new_ci); - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_FILE_DIRECTORY, 0, + path, old_path, NULL, NULL, _("CONFLICT (file/directory): directory in the way " "of %s from %s; moving it to %s instead."), old_path, branch, path); @@ -3764,15 +3914,23 @@ static void process_entry(struct merge_options *opt, rename_b = 1; } + if (rename_a) + a_path = unique_path(opt, path, opt->branch1); + if (rename_b) + b_path = unique_path(opt, path, opt->branch2); + if (rename_a && rename_b) { - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_DISTINCT_MODES, 0, + path, a_path, b_path, NULL, _("CONFLICT (distinct types): %s had " "different types on each side; " "renamed both of them so each can " "be recorded somewhere."), path); } else { - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_DISTINCT_MODES, 0, + path, rename_a ? a_path : b_path, + NULL, NULL, _("CONFLICT (distinct types): %s had " "different types on each side; " "renamed one of them so each can be " @@ -3809,14 +3967,10 @@ static void process_entry(struct merge_options *opt, /* Insert entries into opt->priv_paths */ assert(rename_a || rename_b); - if (rename_a) { - a_path = unique_path(opt, path, opt->branch1); + if (rename_a) strmap_put(&opt->priv->paths, a_path, ci); - } - if (rename_b) - b_path = unique_path(opt, path, opt->branch2); - else + if (!rename_b) b_path = path; strmap_put(&opt->priv->paths, b_path, new_ci); @@ -3867,7 +4021,8 @@ static void process_entry(struct merge_options *opt, reason = _("add/add"); if (S_ISGITLINK(merged_file.mode)) reason = _("submodule"); - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_CONTENTS, 0, + path, NULL, NULL, NULL, _("CONFLICT (%s): Merge conflict in %s"), reason, path); } @@ -3911,7 +4066,8 @@ static void process_entry(struct merge_options *opt, * since the contents were not modified. */ } else { - path_msg(opt, path, 0, + path_msg(opt, CONFLICT_MODIFY_DELETE, 0, + path, NULL, NULL, NULL, _("CONFLICT (modify/delete): %s deleted in %s " "and modified in %s. Version %s of %s left " "in tree."), @@ -4207,7 +4363,8 @@ static int record_conflicted_index_entries(struct merge_options *opt) path, "cruft"); - path_msg(opt, path, 1, + path_msg(opt, CONFLICT_PRESENT_DESPITE_SKIPPED, 1, + path, NULL, NULL, NULL, _("Note: %s not up to date and in way of checking out conflicted version; old copy renamed to %s"), path, new_name); errs |= rename(path, new_name); From de90581141a886a79cccd0d9adb76814f3e1ab2c Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:57 +0000 Subject: [PATCH 14/17] merge-ort: optionally produce machine-readable output With the new `detailed` parameter, a new mode can be triggered when displaying the merge messages: The `detailed` mode prints NUL-delimited fields of the following form: NUL ... NUL NUL The `` field determines how many `` fields there are. The intention of this mode is to support server-side operations, where worktree-less merges can lead to conflicts and depending on the type and/or path count, the caller might know how to handle said conflict. Signed-off-by: Elijah Newren Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- builtin/merge-tree.c | 3 ++- merge-ort.c | 22 ++++++++++++++++++++-- merge-ort.h | 1 + 3 files changed, 23 insertions(+), 3 deletions(-) diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index c61b5b4a10..b3c5692498 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -468,7 +468,8 @@ static int real_merge(struct merge_tree_options *o, } if (o->show_messages) { putchar(line_termination); - merge_display_update_messages(&opt, &result); + merge_display_update_messages(&opt, line_termination == '\0', + &result); } merge_finalize(&opt, &result); return !result.clean; /* result.clean < 0 handled above */ diff --git a/merge-ort.c b/merge-ort.c index 6081b29705..01f150ef3b 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -4413,6 +4413,7 @@ static int record_conflicted_index_entries(struct merge_options *opt) } void merge_display_update_messages(struct merge_options *opt, + int detailed, struct merge_result *result) { struct merge_options_internal *opti = result->priv; @@ -4438,8 +4439,25 @@ void merge_display_update_messages(struct merge_options *opt, /* Iterate over the items, printing them */ for (int path_nr = 0; path_nr < olist.nr; ++path_nr) { struct string_list *conflicts = olist.items[path_nr].util; - for (int i = 0; i < conflicts->nr; i++) + for (int i = 0; i < conflicts->nr; i++) { + struct logical_conflict_info *info = + conflicts->items[i].util; + + if (detailed) { + printf("%lu", (unsigned long)info->paths.nr); + putchar('\0'); + for (int n = 0; n < info->paths.nr; n++) { + fputs(info->paths.v[n], stdout); + putchar('\0'); + } + fputs(type_short_descriptions[info->type], + stdout); + putchar('\0'); + } puts(conflicts->items[i].string); + if (detailed) + putchar('\0'); + } } string_list_clear(&olist, 0); @@ -4519,7 +4537,7 @@ void merge_switch_to_result(struct merge_options *opt, trace2_region_leave("merge", "write_auto_merge", opt->repo); } if (display_update_msgs) - merge_display_update_messages(opt, result); + merge_display_update_messages(opt, /* detailed */ 0, result); merge_finalize(opt, result); } diff --git a/merge-ort.h b/merge-ort.h index c4909bcbf9..a994c9a5fc 100644 --- a/merge-ort.h +++ b/merge-ort.h @@ -87,6 +87,7 @@ void merge_switch_to_result(struct merge_options *opt, * so only call this when bypassing merge_switch_to_result(). */ void merge_display_update_messages(struct merge_options *opt, + int detailed, struct merge_result *result); struct stage_info { From 7c48b27822b280222be1df7ec9f9e98d688f933b Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:58 +0000 Subject: [PATCH 15/17] merge-tree: allow `ls-files -u` style info to be NUL terminated Much as `git ls-files` has a -z option, let's add one to merge-tree so that the conflict-info section can be NUL terminated (and avoid quoting of unusual filenames). Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- Documentation/git-merge-tree.txt | 21 +++++++++++++--- builtin/merge-tree.c | 4 ++- t/t4301-merge-tree-write-tree.sh | 42 ++++++++++++++++++++++++++++++++ 3 files changed, 62 insertions(+), 5 deletions(-) diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt index b89aabdb98..75b57f8aba 100644 --- a/Documentation/git-merge-tree.txt +++ b/Documentation/git-merge-tree.txt @@ -40,6 +40,12 @@ After the merge completes, a new toplevel tree object is created. See OPTIONS ------- +-z:: + Do not quote filenames in the section, + and end each filename with a NUL character rather than + newline. Also begin the messages section with a NUL character + instead of a newline. See <> below for more information. + --name-only:: In the Conflicted file info section, instead of writing a list of (mode, oid, stage, path) tuples to output for conflicted @@ -76,7 +82,8 @@ OID of toplevel tree This is a tree object that represents what would be checked out in the working tree at the end of `git merge`. If there were conflicts, then -files within this tree may have embedded conflict markers. +files within this tree may have embedded conflict markers. This section +is always followed by a newline (or NUL if `-z` is passed). [[CFI]] Conflicted file info @@ -89,20 +96,26 @@ This is a sequence of lines with the format The filename will be quoted as explained for the configuration variable `core.quotePath` (see linkgit:git-config[1]). However, if the `--name-only` option is passed, the mode, object, and stage will -be omitted. +be omitted. If `-z` is passed, the "lines" are terminated by a NUL +character instead of a newline character. [[IM]] Informational messages ~~~~~~~~~~~~~~~~~~~~~~ -This always starts with a blank line to separate it from the previous -sections, and then has free-form messages about the merge, such as: +This always starts with a blank line (or NUL if `-z` is passed) to +separate it from the previous sections, and then has free-form +messages about the merge, such as: * "Auto-merging " * "CONFLICT (rename/delete): renamed...but deleted in..." * "Failed to merge submodule ()" * "Warning: cannot merge binary files: " +Note that these free-form messages will never have a NUL character +in or between them, even if -z is passed. It is simply a large block +of text taking up the remainder of the output. + EXIT STATUS ----------- diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index b3c5692498..c159e31774 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -445,7 +445,7 @@ static int real_merge(struct merge_tree_options *o, if (o->show_messages == -1) o->show_messages = !result.clean; - puts(oid_to_hex(&result.tree->object.oid)); + printf("%s%c", oid_to_hex(&result.tree->object.oid), line_termination); if (!result.clean) { struct string_list conflicted_files = STRING_LIST_INIT_NODUP; const char *last = NULL; @@ -494,6 +494,8 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) N_("do a trivial merge only"), MODE_TRIVIAL), OPT_BOOL(0, "messages", &o.show_messages, N_("also show informational/conflict messages")), + OPT_SET_INT('z', NULL, &line_termination, + N_("separate paths with the NUL character"), '\0'), OPT_BOOL_F(0, "name-only", &o.name_only, N_("list filenames without modes/oids/stages"), diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh index 0ec5f0d3f7..88e75b18cc 100755 --- a/t/t4301-merge-tree-write-tree.sh +++ b/t/t4301-merge-tree-write-tree.sh @@ -173,4 +173,46 @@ test_expect_success 'Check conflicted oids and modes without messages' ' test_cmp conflicted-file-info actual ' +test_expect_success 'NUL terminated conflicted file "lines"' ' + git checkout -b tweak1 side1 && + test_write_lines zero 1 2 3 4 5 6 >numbers && + git add numbers && + git mv numbers "Αυτά μου φαίνονται κινέζικα" && + git commit -m "Renamed numbers" && + + test_expect_code 1 git merge-tree --write-tree -z tweak1 side2 >out && + anonymize_hash out >actual && + printf "\\n" >>actual && + + # Expected results: + # "greeting" should merge with conflicts + # "whatever" has *both* a modify/delete and a file/directory conflict + # "Αυτά μου φαίνονται κινέζικα" should have a conflict + echo HASH | lf_to_nul >expect && + + q_to_tab <<-EOF | lf_to_nul >>expect && + 100644 HASH 1Qgreeting + 100644 HASH 2Qgreeting + 100644 HASH 3Qgreeting + 100644 HASH 1Qwhatever~tweak1 + 100644 HASH 2Qwhatever~tweak1 + 100644 HASH 1QΑυτά μου φαίνονται κινέζικα + 100644 HASH 2QΑυτά μου φαίνονται κινέζικα + 100644 HASH 3QΑυτά μου φαίνονται κινέζικα + + EOF + + q_to_nul <<-EOF >>expect && + 1QgreetingQAuto-mergingQAuto-merging greeting + Q1QgreetingQCONFLICT (contents)QCONFLICT (content): Merge conflict in greeting + Q2Qwhatever~tweak1QwhateverQCONFLICT (file/directory)QCONFLICT (file/directory): directory in the way of whatever from tweak1; moving it to whatever~tweak1 instead. + Q1Qwhatever~tweak1QCONFLICT (modify/delete)QCONFLICT (modify/delete): whatever~tweak1 deleted in side2 and modified in tweak1. Version tweak1 of whatever~tweak1 left in tree. + Q1QΑυτά μου φαίνονται κινέζικαQAuto-mergingQAuto-merging Αυτά μου φαίνονται κινέζικα + Q1QΑυτά μου φαίνονται κινέζικαQCONFLICT (contents)QCONFLICT (content): Merge conflict in Αυτά μου φαίνονται κινέζικα + Q + EOF + + test_cmp expect actual +' + test_done From 7976721d171e17330486b403e868b594cd238295 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:20:59 +0000 Subject: [PATCH 16/17] merge-tree: add a --allow-unrelated-histories flag Folks may want to merge histories that have no common ancestry; provide a flag with the same name as used by `git merge` to allow this. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- Documentation/git-merge-tree.txt | 5 +++++ builtin/merge-tree.c | 7 ++++++- t/t4301-merge-tree-write-tree.sh | 24 +++++++++++++++++++++++- 3 files changed, 34 insertions(+), 2 deletions(-) diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt index 75b57f8aba..628324646d 100644 --- a/Documentation/git-merge-tree.txt +++ b/Documentation/git-merge-tree.txt @@ -59,6 +59,11 @@ OPTIONS default is to include these messages if there are merge conflicts, and to omit them otherwise. +--allow-unrelated-histories:: + merge-tree will by default error out if the two branches specified + share no common history. This flag can be given to override that + check and make the merge proceed anyway. + [[OUTPUT]] OUTPUT ------ diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c index c159e31774..ae5782917b 100644 --- a/builtin/merge-tree.c +++ b/builtin/merge-tree.c @@ -399,6 +399,7 @@ enum mode { struct merge_tree_options { int mode; + int allow_unrelated_histories; int show_messages; int name_only; }; @@ -434,7 +435,7 @@ static int real_merge(struct merge_tree_options *o, * merge_incore_recursive in merge-ort.h */ merge_bases = get_merge_bases(parent1, parent2); - if (!merge_bases) + if (!merge_bases && !o->allow_unrelated_histories) die(_("refusing to merge unrelated histories")); merge_bases = reverse_commit_list(merge_bases); @@ -500,6 +501,10 @@ int cmd_merge_tree(int argc, const char **argv, const char *prefix) &o.name_only, N_("list filenames without modes/oids/stages"), PARSE_OPT_NONEG), + OPT_BOOL_F(0, "allow-unrelated-histories", + &o.allow_unrelated_histories, + N_("allow merging unrelated histories"), + PARSE_OPT_NONEG), OPT_END() }; diff --git a/t/t4301-merge-tree-write-tree.sh b/t/t4301-merge-tree-write-tree.sh index 88e75b18cc..f091259a55 100755 --- a/t/t4301-merge-tree-write-tree.sh +++ b/t/t4301-merge-tree-write-tree.sh @@ -44,7 +44,13 @@ test_expect_success setup ' git checkout side3 && git mv numbers sequence && test_tick && - git commit -m rename-numbers + git commit -m rename-numbers && + + git switch --orphan unrelated && + >something-else && + git add something-else && + test_tick && + git commit -m first-commit ' test_expect_success 'Clean merge' ' @@ -215,4 +221,20 @@ test_expect_success 'NUL terminated conflicted file "lines"' ' test_cmp expect actual ' +test_expect_success 'error out by default for unrelated histories' ' + test_expect_code 128 git merge-tree --write-tree side1 unrelated 2>error && + + grep "refusing to merge unrelated histories" error +' + +test_expect_success 'can override merge of unrelated histories' ' + git merge-tree --write-tree --allow-unrelated-histories side1 unrelated >tree && + TREE=$(cat tree) && + + git rev-parse side1:numbers side1:greeting side1:whatever unrelated:something-else >expect && + git rev-parse $TREE:numbers $TREE:greeting $TREE:whatever $TREE:something-else >actual && + + test_cmp expect actual +' + test_done From 7260e87248e743b197d34c1caf3949ae4fa3bc12 Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 18 Jun 2022 00:21:00 +0000 Subject: [PATCH 17/17] git-merge-tree.txt: add a section on potentional usage mistakes Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- Documentation/git-merge-tree.txt | 53 ++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/Documentation/git-merge-tree.txt b/Documentation/git-merge-tree.txt index 628324646d..d6c356740e 100644 --- a/Documentation/git-merge-tree.txt +++ b/Documentation/git-merge-tree.txt @@ -156,6 +156,59 @@ with linkgit:git-merge[1]: * any messages that would have been printed to stdout (the <>) +MISTAKES TO AVOID +----------------- + +Do NOT look through the resulting toplevel tree to try to find which +files conflict; parse the <> section instead. +Not only would parsing an entire tree be horrendously slow in large +repositories, there are numerous types of conflicts not representable by +conflict markers (modify/delete, mode conflict, binary file changed on +both sides, file/directory conflicts, various rename conflict +permutations, etc.) + +Do NOT interpret an empty <> list as a clean +merge; check the exit status. A merge can have conflicts without having +individual files conflict (there are a few types of directory rename +conflicts that fall into this category, and others might also be added +in the future). + +Do NOT attempt to guess or make the user guess the conflict types from +the <> list. The information there is +insufficient to do so. For example: Rename/rename(1to2) conflicts (both +sides renamed the same file differently) will result in three different +file having higher order stages (but each only has one higher order +stage), with no way (short of the <> section) +to determine which three files are related. File/directory conflicts +also result in a file with exactly one higher order stage. +Possibly-involved-in-directory-rename conflicts (when +"merge.directoryRenames" is unset or set to "conflicts") also result in +a file with exactly one higher order stage. In all cases, the +<> section has the necessary info, though it +is not designed to be machine parseable. + +Do NOT assume that each paths from <>, and +the logical conflicts in the <> have a +one-to-one mapping, nor that there is a one-to-many mapping, nor a +many-to-one mapping. Many-to-many mappings exist, meaning that each +path can have many logical conflict types in a single merge, and each +logical conflict type can affect many paths. + +Do NOT assume all filenames listed in the <> +section had conflicts. Messages can be included for files that have no +conflicts, such as "Auto-merging ". + +AVOID taking the OIDS from the <> and +re-merging them to present the conflicts to the user. This will lose +information. Instead, look up the version of the file found within the +<> and show that instead. In particular, +the latter will have conflict markers annotated with the original +branch/commit being merged and, if renames were involved, the original +filename. While you could include the original branch/commit in the +conflict marker annotations when re-merging, the original filename is +not available from the <> and thus you would +be losing information that might help the user resolve the conflict. + [[DEPMERGE]] DEPRECATED DESCRIPTION ----------------------