[PATCHv4 10/21] git notes merge: Initial implementation handling trivial merges only
- From
Johan Herland <johan@herland.net>
- Date
- Oct 21, 2010, 02:08 UTC
- Message-ID
- <1287626936-32232-11-git-send-email-johan@herland.net>
- In-Reply-To
- <1287626936-32232-1-git-send-email-johan@herland.net>
This initial implementation of 'git notes merge' only handles the trivial merge cases (i.e. where the merge is either a no-op, or a fast-forward).
The patch includes testcases for these trivial merge cases.
Future patches will extend the functionality of 'git notes merge'.
This patch has been improved by the following contributions: - Stephen Boyd: Simplify argc logic - Stephen Boyd: Use test_commit - Ævar Arnfjörð Bjarmason: Don't use C99 comments. - Jonathan Nieder: Add constants for common verbosity values - Jonathan Nieder: Use trace_printf(...) instead of OUTPUT(o, 5, ...) - Jonathan Nieder: Remove extraneous show() function - Jonathan Nieder: Clarify handling of empty/missing notes ref in notes_merge()
Thanks-to: Stephen Boyd <bebarino@gmail.com> Thanks-to: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Thanks-to: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Johan Herland <johan@herland.net> --- Makefile | 2 + builtin/notes.c | 54 ++++++++++++++ notes-merge.c | 120 ++++++++++++++++++++++++++++++++ notes-merge.h | 36 ++++++++++ t/t3308-notes-merge.sh | 180 ++++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 392 insertions(+), 0 deletions(-) create mode 100644 notes-merge.c create mode 100644 notes-merge.h create mode 100755 t/t3308-notes-merge.sh
diff --git a/Makefile b/Makefile index f33648d..14c0ff1 100644 --- a/Makefile +++ b/Makefile @@ -503,6 +503,7 @@ LIB_H += mailmap.h LIB_H += merge-recursive.h LIB_H += notes.h LIB_H += notes-cache.h +LIB_H += notes-merge.h LIB_H += object.h LIB_H += pack.h LIB_H += pack-refs.h @@ -593,6 +594,7 @@ LIB_OBJS += merge-recursive.o LIB_OBJS += name-hash.o LIB_OBJS += notes.o LIB_OBJS += notes-cache.o +LIB_OBJS += notes-merge.o LIB_OBJS += object.o LIB_OBJS += pack-check.o LIB_OBJS += pack-refs.o diff --git a/builtin/notes.c b/builtin/notes.c index 9c91c59..fbabdc7 100644 --- a/builtin/notes.c +++ b/builtin/notes.c @@ -17,6 +17,7 @@ #include "run-command.h" #include "parse-options.h" #include "string-list.h" +#include "notes-merge.h" static const char * const git_notes_usage[] = { "git notes [--ref <notes_ref>] [list [<object>]]", @@ -25,6 +26,7 @@ static const char * const git_notes_usage[] = { "git notes [--ref <notes_ref>] append [-m <msg> | -F <file> | (-c | -C) <object>] [<object>]", "git notes [--ref <notes_ref>] edit [<object>]", "git notes [--ref <notes_ref>] show [<object>]", + "git notes [--ref <notes_ref>] merge [-v | -q] <notes_ref>", "git notes [--ref <notes_ref>] remove [<object>]", "git notes [--ref <notes_ref>] prune [-n | -v]", NULL @@ -61,6 +63,11 @@ static const char * const git_notes_show_usage[] = { NULL }; +static const char * const git_notes_merge_usage[] = { + "git notes merge [<options>] <notes_ref>", + NULL +}; + static const char * const git_notes_remove_usage[] = { "git notes remove [<object>]", NULL @@ -772,6 +779,51 @@ static int show(int argc, const char **argv, const char *prefix) return retval; } +static int merge(int argc, const char **argv, const char *prefix) +{ + struct strbuf remote_ref = STRBUF_INIT, msg = STRBUF_INIT; + unsigned char result_sha1[20]; + struct notes_merge_options o; + int verbosity = 0, result; + struct option options[] = { + OPT__VERBOSITY(&verbosity), + OPT_END() + }; + + argc = parse_options(argc, argv, prefix, options, + git_notes_merge_usage, 0); + + if (argc != 1) { + error("Must specify a notes ref to merge"); + usage_with_options(git_notes_merge_usage, options); + } + + init_notes_merge_options(&o); + o.verbosity = verbosity + NOTES_MERGE_VERBOSITY_DEFAULT; + + o.local_ref = default_notes_ref(); + strbuf_addstr(&remote_ref, argv[0]); + expand_notes_ref(&remote_ref); + o.remote_ref = remote_ref.buf; + + result = notes_merge(&o, result_sha1); + + strbuf_addf(&msg, "notes: Merged notes from %s into %s", + remote_ref.buf, default_notes_ref()); + if (result == 0) { /* Merge resulted (trivially) in result_sha1 */ + /* Update default notes ref with new commit */ + update_ref(msg.buf, default_notes_ref(), result_sha1, NULL, + 0, DIE_ON_ERR); + } else { + /* TODO: */ + die("'git notes merge' cannot yet handle non-trivial merges!"); + } + + strbuf_release(&remote_ref); + strbuf_release(&msg); + return 0; +} + static int remove_cmd(int argc, const char **argv, const char *prefix) { struct option options[] = { @@ -865,6 +917,8 @@ int cmd_notes(int argc, const char **argv, const char *prefix) result = append_edit(argc, argv, prefix); else if (!strcmp(argv[0], "show")) result = show(argc, argv, prefix); + else if (!strcmp(argv[0], "merge")) + result = merge(argc, argv, prefix); else if (!strcmp(argv[0], "remove")) result = remove_cmd(argc, argv, prefix); else if (!strcmp(argv[0], "prune")) diff --git a/notes-merge.c b/notes-merge.c new file mode 100644 index 0000000..cd917f9 --- /dev/null +++ b/notes-merge.c @@ -0,0 +1,120 @@ +#include "cache.h" +#include "commit.h" +#include "refs.h" +#include "notes-merge.h" + +void init_notes_merge_options(struct notes_merge_options *o) +{ + memset(o, 0, sizeof(struct notes_merge_options)); + o->verbosity = NOTES_MERGE_VERBOSITY_DEFAULT; +} + +#define OUTPUT(o, v, ...) \ + do { \ + if ((o)->verbosity >= (v)) { \ + printf(__VA_ARGS__); \ + puts(""); \ + } \ + } while (0) + +int notes_merge(struct notes_merge_options *o, + unsigned char *result_sha1) +{ + unsigned char local_sha1[20], remote_sha1[20]; + struct commit *local, *remote; + struct commit_list *bases = NULL; + const unsigned char *base_sha1; + int result = 0; + + assert(o->local_ref && o->remote_ref); + hashclr(result_sha1); + + trace_printf("notes_merge(o->local_ref = %s, o->remote_ref = %s)\n", + o->local_ref, o->remote_ref); + + /* Dereference o->local_ref into local_sha1 */ + if (!resolve_ref(o->local_ref, local_sha1, 0, NULL)) + die("Failed to resolve local notes ref '%s'", o->local_ref); + else if (!check_ref_format(o->local_ref) && is_null_sha1(local_sha1)) + local = NULL; /* local_sha1 == null_sha1 indicates unborn ref */ + else if (!(local = lookup_commit_reference(local_sha1))) + die("Could not parse local commit %s (%s)", + sha1_to_hex(local_sha1), o->local_ref); + trace_printf("\tlocal commit: %.7s\n", sha1_to_hex(local_sha1)); + + /* Dereference o->remote_ref into remote_sha1 */ + if (get_sha1(o->remote_ref, remote_sha1)) { + /* + * Failed to get remote_sha1. If o->remote_ref looks like an + * unborn ref, perform the merge using an empty notes tree. + */ + if (!check_ref_format(o->remote_ref)) { + hashclr(remote_sha1); + remote = NULL; + } + else + die("Failed to resolve remote notes ref '%s'", + o->remote_ref); + } + else if (!(remote = lookup_commit_reference(remote_sha1))) + die("Could not parse remote commit %s (%s)", + sha1_to_hex(remote_sha1), o->remote_ref); + trace_printf("\tremote commit: %.7s\n", sha1_to_hex(remote_sha1)); + + if (!local && !remote) + die("Cannot merge empty notes ref (%s) into empty notes ref " + "(%s)", o->remote_ref, o->local_ref); + if (!local) { + /* result == remote commit */ + hashcpy(result_sha1, remote_sha1); + goto found_result; + } + if (!remote) { + /* result == local commit */ + hashcpy(result_sha1, local_sha1); + goto found_result; + } + assert(local && remote); + + /* Find merge bases */ + bases = get_merge_bases(local, remote, 1); + if (!bases) { + base_sha1 = null_sha1; + OUTPUT(o, 4, "No merge base found; doing history-less merge"); + } else if (!bases->next) { + base_sha1 = bases->item->object.sha1; + OUTPUT(o, 4, "One merge base found (%.7s)", + sha1_to_hex(base_sha1)); + } else { + /* TODO: How to handle multiple merge-bases? */ + base_sha1 = bases->item->object.sha1; + OUTPUT(o, 3, "Multiple merge bases found. Using the first " + "(%.7s)", sha1_to_hex(base_sha1)); + } + + OUTPUT(o, 4, "Merging remote commit %.7s into local commit %.7s with " + "merge-base %.7s", sha1_to_hex(remote->object.sha1), + sha1_to_hex(local->object.sha1), sha1_to_hex(base_sha1)); + + if (!hashcmp(remote->object.sha1, base_sha1)) { + /* Already merged; result == local commit */ + OUTPUT(o, 2, "Already up-to-date!"); + hashcpy(result_sha1, local->object.sha1); + goto found_result; + } + if (!hashcmp(local->object.sha1, base_sha1)) { + /* Fast-forward; result == remote commit */ + OUTPUT(o, 2, "Fast-forward"); + hashcpy(result_sha1, remote->object.sha1); + goto found_result; + } + + /* TODO: */ + result = error("notes_merge() cannot yet handle real merges."); + +found_result: + free_commit_list(bases); + trace_printf("notes_merge(): result = %i, result_sha1 = %.7s\n", + result, sha1_to_hex(result_sha1)); + return result; +} diff --git a/notes-merge.h b/notes-merge.h new file mode 100644 index 0000000..fd572ac --- /dev/null +++ b/notes-merge.h @@ -0,0 +1,36 @@ +#ifndef NOTES_MERGE_H +#define NOTES_MERGE_H + +enum notes_merge_verbosity { + NOTES_MERGE_VERBOSITY_DEFAULT = 2, + NOTES_MERGE_VERBOSITY_MAX = 5 +}; + +struct notes_merge_options { + const char *local_ref; + const char *remote_ref; + int verbosity; +}; + +void init_notes_merge_options(struct notes_merge_options *o); + +/* + * Merge notes from o->remote_ref into o->local_ref + * + * The commits given by the two refs are merged, producing one of the following + * outcomes: + * + * 1. The merge trivially results in an existing commit (e.g. fast-forward or + * already-up-to-date). The SHA1 of the result is written into 'result_sha1' + * and 0 is returned. + * 2. The merge fails. result_sha1 is set to null_sha1, and non-zero returned. + * + * Both o->local_ref and o->remote_ref must be given (non-NULL), but either ref + * (although not both) may refer to a non-existing notes ref, in which case + * that notes ref is interpreted as an empty notes tree, and the merge + * trivially results in what the other ref points to. + */ +int notes_merge(struct notes_merge_options *o, + unsigned char *result_sha1); + +#endif diff --git a/t/t3308-notes-merge.sh b/t/t3308-notes-merge.sh new file mode 100755 index 0000000..9acb684 --- /dev/null +++ b/t/t3308-notes-merge.sh @@ -0,0 +1,180 @@ +#!/bin/sh +# +# Copyright (c) 2010 Johan Herland +# + +test_description='Test merging of notes trees' + +. ./test-lib.sh + +test_expect_success setup ' + test_commit 1st && + test_commit 2nd && + test_commit 3rd && + test_commit 4th && + test_commit 5th && + # Create notes on 4 first commits + git config core.notesRef refs/notes/x && + git notes add -m "Notes on 1st commit" 1st && + git notes add -m "Notes on 2nd commit" 2nd && + git notes add -m "Notes on 3rd commit" 3rd && + git notes add -m "Notes on 4th commit" 4th +' + +commit_sha1=$(git rev-parse 1st^{commit}) +commit_sha2=$(git rev-parse 2nd^{commit}) +commit_sha3=$(git rev-parse 3rd^{commit}) +commit_sha4=$(git rev-parse 4th^{commit}) +commit_sha5=$(git rev-parse 5th^{commit}) + +verify_notes () { + notes_ref="$1" + git -c core.notesRef="refs/notes/$notes_ref" notes | + sort >"output_notes_$notes_ref" && + test_cmp "expect_notes_$notes_ref" "output_notes_$notes_ref" && + git -c core.notesRef="refs/notes/$notes_ref" log --format="%H %s%n%N" \ + >"output_log_$notes_ref" && + test_cmp "expect_log_$notes_ref" "output_log_$notes_ref" +} + +cat <<EOF | sort >expect_notes_x +5e93d24084d32e1cb61f7070505b9d2530cca987 $commit_sha4 +8366731eeee53787d2bdf8fc1eff7d94757e8da0 $commit_sha3 +eede89064cd42441590d6afec6c37b321ada3389 $commit_sha2 +daa55ffad6cb99bf64226532147ffcaf5ce8bdd1 $commit_sha1 +EOF + +cat >expect_log_x <<EOF +$commit_sha5 5th + +$commit_sha4 4th +Notes on 4th commit + +$commit_sha3 3rd +Notes on 3rd commit + +$commit_sha2 2nd +Notes on 2nd commit + +$commit_sha1 1st +Notes on 1st commit + +EOF + +test_expect_success 'verify initial notes (x)' ' + verify_notes x +' + +cp expect_notes_x expect_notes_y +cp expect_log_x expect_log_y + +test_expect_success 'fail to merge empty notes ref into empty notes ref (z => y)' ' + test_must_fail git -c "core.notesRef=refs/notes/y" notes merge z +' + +test_expect_success 'fail to merge into various non-notes refs' ' + test_must_fail git -c "core.notesRef=refs/notes" notes merge x && + test_must_fail git -c "core.notesRef=refs/notes/" notes merge x && + mkdir -p .git/refs/notes/dir && + test_must_fail git -c "core.notesRef=refs/notes/dir" notes merge x && + test_must_fail git -c "core.notesRef=refs/notes/dir/" notes merge x && + test_must_fail git -c "core.notesRef=refs/heads/master" notes merge x && + test_must_fail git -c "core.notesRef=refs/notes/y:" notes merge x && + test_must_fail git -c "core.notesRef=refs/notes/y:foo" notes merge x && + test_must_fail git -c "core.notesRef=refs/notes/foo^{bar" notes merge x +' + +test_expect_success 'fail to merge various non-note-trees' ' + git config core.notesRef refs/notes/y && + test_must_fail git notes merge refs/notes && + test_must_fail git notes merge refs/notes/ && + test_must_fail git notes merge refs/notes/dir && + test_must_fail git notes merge refs/notes/dir/ && + test_must_fail git notes merge refs/heads/master && + test_must_fail git notes merge x: && + test_must_fail git notes merge x:foo && + test_must_fail git notes merge foo^{bar +' + +test_expect_success 'merge notes into empty notes ref (x => y)' ' + git config core.notesRef refs/notes/y && + git notes merge x && + verify_notes y && + # x and y should point to the same notes commit + test "$(git rev-parse refs/notes/x)" = "$(git rev-parse refs/notes/y)" +' + +test_expect_success 'merge empty notes ref (z => y)' ' + git notes merge z && + # y should not change (still == x) + test "$(git rev-parse refs/notes/x)" = "$(git rev-parse refs/notes/y)" +' + +test_expect_success 'change notes on other notes ref (y)' ' + # Not touching notes to 1st commit + git notes remove 2nd && + git notes append -m "More notes on 3rd commit" 3rd && + git notes add -f -m "New notes on 4th commit" 4th && + git notes add -m "Notes on 5th commit" 5th +' + +test_expect_success 'merge previous notes commit (y^ => y) => No-op' ' + pre_state="$(git rev-parse refs/notes/y)" && + git notes merge y^ && + # y should not move + test "$pre_state" = "$(git rev-parse refs/notes/y)" +' + +cat <<EOF | sort >expect_notes_y +0f2efbd00262f2fd41dfae33df8765618eeacd99 $commit_sha5 +dec2502dac3ea161543f71930044deff93fa945c $commit_sha4 +4069cdb399fd45463ec6eef8e051a16a03592d91 $commit_sha3 +daa55ffad6cb99bf64226532147ffcaf5ce8bdd1 $commit_sha1 +EOF + +cat >expect_log_y <<EOF +$commit_sha5 5th +Notes on 5th commit + +$commit_sha4 4th +New notes on 4th commit + +$commit_sha3 3rd +Notes on 3rd commit + +More notes on 3rd commit + +$commit_sha2 2nd + +$commit_sha1 1st +Notes on 1st commit + +EOF + +test_expect_success 'verify changed notes on other notes ref (y)' ' + verify_notes y +' + +test_expect_success 'verify unchanged notes on original notes ref (x)' ' + verify_notes x +' + +test_expect_success 'merge original notes (x) into changed notes (y) => No-op' ' + git notes merge -vvv x && + verify_notes y && + verify_notes x +' + +cp expect_notes_y expect_notes_x +cp expect_log_y expect_log_x + +test_expect_success 'merge changed (y) into original (x) => Fast-forward' ' + git config core.notesRef refs/notes/x && + git notes merge y && + verify_notes x && + verify_notes y && + # x and y should point to same the notes commit + test "$(git rev-parse refs/notes/x)" = "$(git rev-parse refs/notes/y)" +' + +test_done
-- 1.7.3.98.g5ad7d9