From 04d3d3cfc4a26f003c5ae2b5598cc975a31e4395 Mon Sep 17 00:00:00 2001 From: Ramkumar Ramachandra Date: Thu, 4 Aug 2011 16:09:08 +0530 Subject: [PATCH] revert: Save data for continuing after conflict resolution Ever since v1.7.2-rc1~4^2~7 (revert: allow cherry-picking more than one commit, 2010-06-02), a single invocation of "git cherry-pick" or "git revert" can perform picks of several individual commits. To implement features like "--continue" to continue the whole operation, we will need to store some information about the state and the plan at the beginning. Introduce a ".git/sequencer/head" file to store this state, and ".git/sequencer/todo" file to store the plan. The head file contains the SHA-1 of the HEAD before the start of the operation, and the todo file contains an instruction sheet whose format is inspired by the format of the "rebase -i" instruction sheet. As a result, a typical todo file looks like: pick 8537f0e submodule add: test failure when url is not configured pick 4d68932 submodule add: allow relative repository path pick f22a17e submodule add: clean up duplicated code pick 59a5775 make copy_ref globally available Since SHA-1 hex is abbreviated using an find_unique_abbrev(), it is unambiguous. This does not guarantee that there will be no ambiguity when more objects are added to the repository. These two files alone are not enough to implement a "--continue" that remembers the command-line options specified; later patches in the series save them too. These new files are unrelated to the existing .git/CHERRY_PICK_HEAD, which will still be useful while committing after a conflict resolution. Inspired-by: Christian Couder Helped-by: Junio C Hamano Helped-by: Jonathan Nieder Signed-off-by: Ramkumar Ramachandra Signed-off-by: Jonathan Nieder Signed-off-by: Junio C Hamano --- builtin/revert.c | 134 +++++++++++++++++++++++++++++++- t/t3510-cherry-pick-sequence.sh | 48 ++++++++++++ 2 files changed, 178 insertions(+), 4 deletions(-) create mode 100755 t/t3510-cherry-pick-sequence.sh diff --git a/builtin/revert.c b/builtin/revert.c index f75c9cb6c..54df8a23b 100644 --- a/builtin/revert.c +++ b/builtin/revert.c @@ -13,6 +13,7 @@ #include "rerere.h" #include "merge-recursive.h" #include "refs.h" +#include "dir.h" /* * This implements the builtins revert and cherry-pick. @@ -60,6 +61,10 @@ struct replay_opts { #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION" +#define SEQ_DIR "sequencer" +#define SEQ_HEAD_FILE "sequencer/head" +#define SEQ_TODO_FILE "sequencer/todo" + static const char *action_name(const struct replay_opts *opts) { return opts->action == REVERT ? "revert" : "cherry-pick"; @@ -587,10 +592,116 @@ static void read_and_refresh_cache(struct replay_opts *opts) rollback_lock_file(&index_lock); } -static int pick_commits(struct replay_opts *opts) +/* + * Append a commit to the end of the commit_list. + * + * next starts by pointing to the variable that holds the head of an + * empty commit_list, and is updated to point to the "next" field of + * the last item on the list as new commits are appended. + * + * Usage example: + * + * struct commit_list *list; + * struct commit_list **next = &list; + * + * next = commit_list_append(c1, next); + * next = commit_list_append(c2, next); + * assert(commit_list_count(list) == 2); + * return list; + */ +struct commit_list **commit_list_append(struct commit *commit, + struct commit_list **next) +{ + struct commit_list *new = xmalloc(sizeof(struct commit_list)); + new->item = commit; + *next = new; + new->next = NULL; + return &new->next; +} + +static int format_todo(struct strbuf *buf, struct commit_list *todo_list, + struct replay_opts *opts) +{ + struct commit_list *cur = NULL; + struct commit_message msg = { NULL, NULL, NULL, NULL, NULL }; + const char *sha1_abbrev = NULL; + const char *action_str = opts->action == REVERT ? "revert" : "pick"; + + for (cur = todo_list; cur; cur = cur->next) { + sha1_abbrev = find_unique_abbrev(cur->item->object.sha1, DEFAULT_ABBREV); + if (get_message(cur->item, &msg)) + return error(_("Cannot get commit message for %s"), sha1_abbrev); + strbuf_addf(buf, "%s %s %s\n", action_str, sha1_abbrev, msg.subject); + } + return 0; +} + +static void walk_revs_populate_todo(struct commit_list **todo_list, + struct replay_opts *opts) { struct rev_info revs; struct commit *commit; + struct commit_list **next; + + prepare_revs(&revs, opts); + + next = todo_list; + while ((commit = get_revision(&revs))) + next = commit_list_append(commit, next); +} + +static void create_seq_dir(void) +{ + const char *seq_dir = git_path(SEQ_DIR); + + if (!(file_exists(seq_dir) && is_directory(seq_dir)) + && mkdir(seq_dir, 0777) < 0) + die_errno(_("Could not create sequencer directory '%s'."), seq_dir); +} + +static void save_head(const char *head) +{ + const char *head_file = git_path(SEQ_HEAD_FILE); + static struct lock_file head_lock; + struct strbuf buf = STRBUF_INIT; + int fd; + + fd = hold_lock_file_for_update(&head_lock, head_file, LOCK_DIE_ON_ERROR); + strbuf_addf(&buf, "%s\n", head); + if (write_in_full(fd, buf.buf, buf.len) < 0) + die_errno(_("Could not write to %s."), head_file); + if (commit_lock_file(&head_lock) < 0) + die(_("Error wrapping up %s."), head_file); +} + +static void save_todo(struct commit_list *todo_list, struct replay_opts *opts) +{ + const char *todo_file = git_path(SEQ_TODO_FILE); + static struct lock_file todo_lock; + struct strbuf buf = STRBUF_INIT; + int fd; + + fd = hold_lock_file_for_update(&todo_lock, todo_file, LOCK_DIE_ON_ERROR); + if (format_todo(&buf, todo_list, opts) < 0) + die(_("Could not format %s."), todo_file); + if (write_in_full(fd, buf.buf, buf.len) < 0) { + strbuf_release(&buf); + die_errno(_("Could not write to %s."), todo_file); + } + if (commit_lock_file(&todo_lock) < 0) { + strbuf_release(&buf); + die(_("Error wrapping up %s."), todo_file); + } + strbuf_release(&buf); +} + +static int pick_commits(struct replay_opts *opts) +{ + struct commit_list *todo_list = NULL; + struct strbuf buf = STRBUF_INIT; + unsigned char sha1[20]; + struct commit_list *cur; + int res; setenv(GIT_REFLOG_ACTION, action_name(opts), 0); if (opts->allow_ff) @@ -598,14 +709,29 @@ static int pick_commits(struct replay_opts *opts) opts->record_origin || opts->edit)); read_and_refresh_cache(opts); - prepare_revs(&revs, opts); + walk_revs_populate_todo(&todo_list, opts); + create_seq_dir(); + if (get_sha1("HEAD", sha1)) { + if (opts->action == REVERT) + die(_("Can't revert as initial commit")); + die(_("Can't cherry-pick into empty head")); + } + save_head(sha1_to_hex(sha1)); - while ((commit = get_revision(&revs))) { - int res = do_pick_commit(commit, opts); + for (cur = todo_list; cur; cur = cur->next) { + save_todo(cur, opts); + res = do_pick_commit(cur->item, opts); if (res) return res; } + /* + * Sequence of picks finished successfully; cleanup by + * removing the .git/sequencer directory + */ + strbuf_addf(&buf, "%s", git_path(SEQ_DIR)); + remove_dir_recursively(&buf, 0); + strbuf_release(&buf); return 0; } diff --git a/t/t3510-cherry-pick-sequence.sh b/t/t3510-cherry-pick-sequence.sh new file mode 100755 index 000000000..a2c70ad4b --- /dev/null +++ b/t/t3510-cherry-pick-sequence.sh @@ -0,0 +1,48 @@ +#!/bin/sh + +test_description='Test cherry-pick continuation features + + + anotherpick: rewrites foo to d + + picked: rewrites foo to c + + unrelatedpick: rewrites unrelated to reallyunrelated + + base: rewrites foo to b + + initial: writes foo as a, unrelated as unrelated + +' + +. ./test-lib.sh + +pristine_detach () { + rm -rf .git/sequencer && + git checkout -f "$1^0" && + git read-tree -u --reset HEAD && + git clean -d -f -f -q -x +} + +test_expect_success setup ' + echo unrelated >unrelated && + git add unrelated && + test_commit initial foo a && + test_commit base foo b && + test_commit unrelatedpick unrelated reallyunrelated && + test_commit picked foo c && + test_commit anotherpick foo d && + git config advice.detachedhead false + +' + +test_expect_success 'cherry-pick persists data on failure' ' + pristine_detach initial && + test_must_fail git cherry-pick base..anotherpick && + test_path_is_dir .git/sequencer && + test_path_is_file .git/sequencer/head && + test_path_is_file .git/sequencer/todo +' + +test_expect_success 'cherry-pick cleans up sequencer state upon success' ' + pristine_detach initial && + git cherry-pick initial..picked && + test_path_is_missing .git/sequencer +' + +test_done -- 2.26.2