diff options
author | Johannes Schindelin <johannes.schindelin@gmx.de> | 2018-04-25 15:28:54 +0300 |
---|---|---|
committer | Junio C Hamano <gitster@pobox.com> | 2018-04-26 06:28:42 +0300 |
commit | 4c68e7ddb59457efe9d3a141dc600feda86cbe67 (patch) | |
tree | b24671648020ee2b0bc59d40559671d8dd056573 /sequencer.c | |
parent | 9055e401dd63a422a4401a454ef2a0e2ef727ace (diff) |
sequencer: introduce the `merge` command
This patch is part of the effort to reimplement `--preserve-merges` with
a substantially improved design, a design that has been developed in the
Git for Windows project to maintain the dozens of Windows-specific patch
series on top of upstream Git.
The previous patch implemented the `label` and `reset` commands to label
commits and to reset to labeled commits. This patch adds the `merge`
command, with the following syntax:
merge [-C <commit>] <rev> # <oneline>
The <commit> parameter in this instance is the *original* merge commit,
whose author and message will be used for the merge commit that is about
to be created.
The <rev> parameter refers to the (possibly rewritten) revision to
merge. Let's see an example of a todo list (the initial `label onto`
command is an auto-generated convenience so that the label `onto` can be
used to refer to the revision onto which we rebase):
label onto
# Branch abc
reset onto
pick deadbeef Hello, world!
label abc
reset onto
pick cafecafe And now for something completely different
merge -C baaabaaa abc # Merge the branch 'abc' into master
To edit the merge commit's message (a "reword" for merges, if you will),
use `-c` (lower-case) instead of `-C`; this convention was borrowed from
`git commit` that also supports `-c` and `-C` with similar meanings.
To create *new* merges, i.e. without copying the commit message from an
existing commit, simply omit the `-C <commit>` parameter (which will
open an editor for the merge message):
merge abc
This comes in handy when splitting a branch into two or more branches.
Note: this patch only adds support for recursive merges, to keep things
simple. Support for octopus merges will be added later in a separate
patch series, support for merges using strategies other than the
recursive merge is left for the future.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'sequencer.c')
-rw-r--r-- | sequencer.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/sequencer.c b/sequencer.c index c9655edffa..94f4831a0c 100644 --- a/sequencer.c +++ b/sequencer.c @@ -1307,6 +1307,7 @@ enum todo_command { TODO_EXEC, TODO_LABEL, TODO_RESET, + TODO_MERGE, /* commands that do nothing but are counted for reporting progress */ TODO_NOOP, TODO_DROP, @@ -1327,6 +1328,7 @@ static struct { { 'x', "exec" }, { 'l', "label" }, { 't', "reset" }, + { 'm', "merge" }, { 0, "noop" }, { 'd', "drop" }, { 0, NULL } @@ -1754,9 +1756,14 @@ static int read_and_refresh_cache(struct replay_opts *opts) return 0; } +enum todo_item_flags { + TODO_EDIT_MERGE_MSG = 1 +}; + struct todo_item { enum todo_command command; struct commit *commit; + unsigned int flags; const char *arg; int arg_len; size_t offset_in_buf; @@ -1791,6 +1798,8 @@ static int parse_insn_line(struct todo_item *item, const char *bol, char *eol) char *end_of_object_name; int i, saved, status, padding; + item->flags = 0; + /* left-trim */ bol += strspn(bol, " \t"); @@ -1840,6 +1849,21 @@ static int parse_insn_line(struct todo_item *item, const char *bol, char *eol) return 0; } + if (item->command == TODO_MERGE) { + if (skip_prefix(bol, "-C", &bol)) + bol += strspn(bol, " \t"); + else if (skip_prefix(bol, "-c", &bol)) { + bol += strspn(bol, " \t"); + item->flags |= TODO_EDIT_MERGE_MSG; + } else { + item->flags |= TODO_EDIT_MERGE_MSG; + item->commit = NULL; + item->arg = bol; + item->arg_len = (int)(eol - bol); + return 0; + } + } + end_of_object_name = (char *) bol + strcspn(bol, " \t\n"); saved = *end_of_object_name; *end_of_object_name = '\0'; @@ -2654,6 +2678,158 @@ static int do_reset(const char *name, int len, struct replay_opts *opts) return ret; } +static int do_merge(struct commit *commit, const char *arg, int arg_len, + int flags, struct replay_opts *opts) +{ + int run_commit_flags = (flags & TODO_EDIT_MERGE_MSG) ? + EDIT_MSG | VERIFY_MSG : 0; + struct strbuf ref_name = STRBUF_INIT; + struct commit *head_commit, *merge_commit, *i; + struct commit_list *bases, *j, *reversed = NULL; + struct merge_options o; + int merge_arg_len, oneline_offset, ret; + static struct lock_file lock; + const char *p; + + if (hold_locked_index(&lock, LOCK_REPORT_ON_ERROR) < 0) { + ret = -1; + goto leave_merge; + } + + head_commit = lookup_commit_reference_by_name("HEAD"); + if (!head_commit) { + ret = error(_("cannot merge without a current revision")); + goto leave_merge; + } + + oneline_offset = arg_len; + merge_arg_len = strcspn(arg, " \t\n"); + p = arg + merge_arg_len; + p += strspn(p, " \t\n"); + if (*p == '#' && (!p[1] || isspace(p[1]))) { + p += 1 + strspn(p + 1, " \t\n"); + oneline_offset = p - arg; + } else if (p - arg < arg_len) + BUG("octopus merges are not supported yet: '%s'", p); + + strbuf_addf(&ref_name, "refs/rewritten/%.*s", merge_arg_len, arg); + merge_commit = lookup_commit_reference_by_name(ref_name.buf); + if (!merge_commit) { + /* fall back to non-rewritten ref or commit */ + strbuf_splice(&ref_name, 0, strlen("refs/rewritten/"), "", 0); + merge_commit = lookup_commit_reference_by_name(ref_name.buf); + } + + if (!merge_commit) { + ret = error(_("could not resolve '%s'"), ref_name.buf); + goto leave_merge; + } + + if (commit) { + const char *message = get_commit_buffer(commit, NULL); + const char *body; + int len; + + if (!message) { + ret = error(_("could not get commit message of '%s'"), + oid_to_hex(&commit->object.oid)); + goto leave_merge; + } + write_author_script(message); + find_commit_subject(message, &body); + len = strlen(body); + ret = write_message(body, len, git_path_merge_msg(), 0); + unuse_commit_buffer(commit, message); + if (ret) { + error_errno(_("could not write '%s'"), + git_path_merge_msg()); + goto leave_merge; + } + } else { + struct strbuf buf = STRBUF_INIT; + int len; + + strbuf_addf(&buf, "author %s", git_author_info(0)); + write_author_script(buf.buf); + strbuf_reset(&buf); + + if (oneline_offset < arg_len) { + p = arg + oneline_offset; + len = arg_len - oneline_offset; + } else { + strbuf_addf(&buf, "Merge branch '%.*s'", + merge_arg_len, arg); + p = buf.buf; + len = buf.len; + } + + ret = write_message(p, len, git_path_merge_msg(), 0); + strbuf_release(&buf); + if (ret) { + error_errno(_("could not write '%s'"), + git_path_merge_msg()); + goto leave_merge; + } + } + + write_message(oid_to_hex(&merge_commit->object.oid), GIT_SHA1_HEXSZ, + git_path_merge_head(), 0); + write_message("no-ff", 5, git_path_merge_mode(), 0); + + bases = get_merge_bases(head_commit, merge_commit); + for (j = bases; j; j = j->next) + commit_list_insert(j->item, &reversed); + free_commit_list(bases); + + read_cache(); + init_merge_options(&o); + o.branch1 = "HEAD"; + o.branch2 = ref_name.buf; + o.buffer_output = 2; + + ret = merge_recursive(&o, head_commit, merge_commit, reversed, &i); + if (ret <= 0) + fputs(o.obuf.buf, stdout); + strbuf_release(&o.obuf); + if (ret < 0) { + error(_("could not even attempt to merge '%.*s'"), + merge_arg_len, arg); + goto leave_merge; + } + /* + * The return value of merge_recursive() is 1 on clean, and 0 on + * unclean merge. + * + * Let's reverse that, so that do_merge() returns 0 upon success and + * 1 upon failed merge (keeping the return value -1 for the cases where + * we will want to reschedule the `merge` command). + */ + ret = !ret; + + if (active_cache_changed && + write_locked_index(&the_index, &lock, COMMIT_LOCK)) { + ret = error(_("merge: Unable to write new index file")); + goto leave_merge; + } + + rollback_lock_file(&lock); + if (ret) + rerere(opts->allow_rerere_auto); + else + /* + * In case of problems, we now want to return a positive + * value (a negative one would indicate that the `merge` + * command needs to be rescheduled). + */ + ret = !!run_git_commit(git_path_merge_msg(), opts, + run_commit_flags); + +leave_merge: + strbuf_release(&ref_name); + rollback_lock_file(&lock); + return ret; +} + static int is_final_fixup(struct todo_list *todo_list) { int i = todo_list->current; @@ -2860,6 +3036,17 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts) } else if (item->command == TODO_RESET) { if ((res = do_reset(item->arg, item->arg_len, opts))) reschedule = 1; + } else if (item->command == TODO_MERGE) { + if ((res = do_merge(item->commit, + item->arg, item->arg_len, + item->flags, opts)) < 0) + reschedule = 1; + else if (res > 0) + /* failed with merge conflicts */ + return error_with_patch(item->commit, + item->arg, + item->arg_len, opts, + res, 0); } else if (!is_noop(item->command)) return error(_("unknown command %d"), item->command); @@ -2871,6 +3058,11 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts) todo_list->current--; if (save_todo(todo_list, opts)) return -1; + if (item->commit) + return error_with_patch(item->commit, + item->arg, + item->arg_len, opts, + res, 0); } todo_list->current++; @@ -3356,8 +3548,16 @@ int transform_todos(unsigned flags) short_commit_name(item->commit) : oid_to_hex(&item->commit->object.oid); + if (item->command == TODO_MERGE) { + if (item->flags & TODO_EDIT_MERGE_MSG) + strbuf_addstr(&buf, " -c"); + else + strbuf_addstr(&buf, " -C"); + } + strbuf_addf(&buf, " %s", oid); } + /* add all the rest */ if (!item->arg_len) strbuf_addch(&buf, '\n'); |