Merge branch 'js/rebase-i-final'

The final batch to "git rebase -i" updates to move more code from
the shell script to C.

* js/rebase-i-final:
  rebase -i: rearrange fixup/squash lines using the rebase--helper
  t3415: test fixup with wrapped oneline
  rebase -i: skip unnecessary picks using the rebase--helper
  rebase -i: check for missing commits in the rebase--helper
  t3404: relax rebase.missingCommitsCheck tests
  rebase -i: also expand/collapse the SHA-1s via the rebase--helper
  rebase -i: do not invent onelines when expanding/collapsing SHA-1s
  rebase -i: remove useless indentation
  rebase -i: generate the script via rebase--helper
  t3415: verify that an empty instructionFormat is handled as before

1 files changed, 531 insertions, 0 deletions

diff --git a/sequencer.c b/sequencer.c
index 60636ce54b..b8c1e876fa 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -20,6 +20,7 @@
 #include "trailer.h"
 #include "log-tree.h"
 #include "wt-status.h"
+#include "hashmap.h"
 
 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 
@@ -2435,3 +2436,533 @@ void append_signoff(struct strbuf *msgbuf, int ignore_footer, unsigned flag)
 
 	strbuf_release(&sob);
 }
+
+int sequencer_make_script(int keep_empty, FILE *out,
+		int argc, const char **argv)
+{
+	char *format = NULL;
+	struct pretty_print_context pp = {0};
+	struct strbuf buf = STRBUF_INIT;
+	struct rev_info revs;
+	struct commit *commit;
+
+	init_revisions(&revs, NULL);
+	revs.verbose_header = 1;
+	revs.max_parents = 1;
+	revs.cherry_pick = 1;
+	revs.limited = 1;
+	revs.reverse = 1;
+	revs.right_only = 1;
+	revs.sort_order = REV_SORT_IN_GRAPH_ORDER;
+	revs.topo_order = 1;
+
+	revs.pretty_given = 1;
+	git_config_get_string("rebase.instructionFormat", &format);
+	if (!format || !*format) {
+		free(format);
+		format = xstrdup("%s");
+	}
+	get_commit_format(format, &revs);
+	free(format);
+	pp.fmt = revs.commit_format;
+	pp.output_encoding = get_log_output_encoding();
+
+	if (setup_revisions(argc, argv, &revs, NULL) > 1)
+		return error(_("make_script: unhandled options"));
+
+	if (prepare_revision_walk(&revs) < 0)
+		return error(_("make_script: error preparing revisions"));
+
+	while ((commit = get_revision(&revs))) {
+		strbuf_reset(&buf);
+		if (!keep_empty && is_original_commit_empty(commit))
+			strbuf_addf(&buf, "%c ", comment_line_char);
+		strbuf_addf(&buf, "pick %s ", oid_to_hex(&commit->object.oid));
+		pretty_print_commit(&pp, commit, &buf);
+		strbuf_addch(&buf, '\n');
+		fputs(buf.buf, out);
+	}
+	strbuf_release(&buf);
+	return 0;
+}
+
+
+int transform_todo_ids(int shorten_ids)
+{
+	const char *todo_file = rebase_path_todo();
+	struct todo_list todo_list = TODO_LIST_INIT;
+	int fd, res, i;
+	FILE *out;
+
+	strbuf_reset(&todo_list.buf);
+	fd = open(todo_file, O_RDONLY);
+	if (fd < 0)
+		return error_errno(_("could not open '%s'"), todo_file);
+	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
+		close(fd);
+		return error(_("could not read '%s'."), todo_file);
+	}
+	close(fd);
+
+	res = parse_insn_buffer(todo_list.buf.buf, &todo_list);
+	if (res) {
+		todo_list_release(&todo_list);
+		return error(_("unusable todo list: '%s'"), todo_file);
+	}
+
+	out = fopen(todo_file, "w");
+	if (!out) {
+		todo_list_release(&todo_list);
+		return error(_("unable to open '%s' for writing"), todo_file);
+	}
+	for (i = 0; i < todo_list.nr; i++) {
+		struct todo_item *item = todo_list.items + i;
+		int bol = item->offset_in_buf;
+		const char *p = todo_list.buf.buf + bol;
+		int eol = i + 1 < todo_list.nr ?
+			todo_list.items[i + 1].offset_in_buf :
+			todo_list.buf.len;
+
+		if (item->command >= TODO_EXEC && item->command != TODO_DROP)
+			fwrite(p, eol - bol, 1, out);
+		else {
+			const char *id = shorten_ids ?
+				short_commit_name(item->commit) :
+				oid_to_hex(&item->commit->object.oid);
+			int len;
+
+			p += strspn(p, " \t"); /* left-trim command */
+			len = strcspn(p, " \t"); /* length of command */
+
+			fprintf(out, "%.*s %s %.*s\n",
+				len, p, id, item->arg_len, item->arg);
+		}
+	}
+	fclose(out);
+	todo_list_release(&todo_list);
+	return 0;
+}
+
+enum check_level {
+	CHECK_IGNORE = 0, CHECK_WARN, CHECK_ERROR
+};
+
+static enum check_level get_missing_commit_check_level(void)
+{
+	const char *value;
+
+	if (git_config_get_value("rebase.missingcommitscheck", &value) ||
+			!strcasecmp("ignore", value))
+		return CHECK_IGNORE;
+	if (!strcasecmp("warn", value))
+		return CHECK_WARN;
+	if (!strcasecmp("error", value))
+		return CHECK_ERROR;
+	warning(_("unrecognized setting %s for option"
+		  "rebase.missingCommitsCheck. Ignoring."), value);
+	return CHECK_IGNORE;
+}
+
+/*
+ * Check if the user dropped some commits by mistake
+ * Behaviour determined by rebase.missingCommitsCheck.
+ * Check if there is an unrecognized command or a
+ * bad SHA-1 in a command.
+ */
+int check_todo_list(void)
+{
+	enum check_level check_level = get_missing_commit_check_level();
+	struct strbuf todo_file = STRBUF_INIT;
+	struct todo_list todo_list = TODO_LIST_INIT;
+	struct strbuf missing = STRBUF_INIT;
+	int advise_to_edit_todo = 0, res = 0, fd, i;
+
+	strbuf_addstr(&todo_file, rebase_path_todo());
+	fd = open(todo_file.buf, O_RDONLY);
+	if (fd < 0) {
+		res = error_errno(_("could not open '%s'"), todo_file.buf);
+		goto leave_check;
+	}
+	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
+		close(fd);
+		res = error(_("could not read '%s'."), todo_file.buf);
+		goto leave_check;
+	}
+	close(fd);
+	advise_to_edit_todo = res =
+		parse_insn_buffer(todo_list.buf.buf, &todo_list);
+
+	if (res || check_level == CHECK_IGNORE)
+		goto leave_check;
+
+	/* Mark the commits in git-rebase-todo as seen */
+	for (i = 0; i < todo_list.nr; i++) {
+		struct commit *commit = todo_list.items[i].commit;
+		if (commit)
+			commit->util = (void *)1;
+	}
+
+	todo_list_release(&todo_list);
+	strbuf_addstr(&todo_file, ".backup");
+	fd = open(todo_file.buf, O_RDONLY);
+	if (fd < 0) {
+		res = error_errno(_("could not open '%s'"), todo_file.buf);
+		goto leave_check;
+	}
+	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
+		close(fd);
+		res = error(_("could not read '%s'."), todo_file.buf);
+		goto leave_check;
+	}
+	close(fd);
+	strbuf_release(&todo_file);
+	res = !!parse_insn_buffer(todo_list.buf.buf, &todo_list);
+
+	/* Find commits in git-rebase-todo.backup yet unseen */
+	for (i = todo_list.nr - 1; i >= 0; i--) {
+		struct todo_item *item = todo_list.items + i;
+		struct commit *commit = item->commit;
+		if (commit && !commit->util) {
+			strbuf_addf(&missing, " - %s %.*s\n",
+				    short_commit_name(commit),
+				    item->arg_len, item->arg);
+			commit->util = (void *)1;
+		}
+	}
+
+	/* Warn about missing commits */
+	if (!missing.len)
+		goto leave_check;
+
+	if (check_level == CHECK_ERROR)
+		advise_to_edit_todo = res = 1;
+
+	fprintf(stderr,
+		_("Warning: some commits may have been dropped accidentally.\n"
+		"Dropped commits (newer to older):\n"));
+
+	/* Make the list user-friendly and display */
+	fputs(missing.buf, stderr);
+	strbuf_release(&missing);
+
+	fprintf(stderr, _("To avoid this message, use \"drop\" to "
+		"explicitly remove a commit.\n\n"
+		"Use 'git config rebase.missingCommitsCheck' to change "
+		"the level of warnings.\n"
+		"The possible behaviours are: ignore, warn, error.\n\n"));
+
+leave_check:
+	strbuf_release(&todo_file);
+	todo_list_release(&todo_list);
+
+	if (advise_to_edit_todo)
+		fprintf(stderr,
+			_("You can fix this with 'git rebase --edit-todo' "
+			  "and then run 'git rebase --continue'.\n"
+			  "Or you can abort the rebase with 'git rebase"
+			  " --abort'.\n"));
+
+	return res;
+}
+
+/* skip picking commits whose parents are unchanged */
+int skip_unnecessary_picks(void)
+{
+	const char *todo_file = rebase_path_todo();
+	struct strbuf buf = STRBUF_INIT;
+	struct todo_list todo_list = TODO_LIST_INIT;
+	struct object_id onto_oid, *oid = &onto_oid, *parent_oid;
+	int fd, i;
+
+	if (!read_oneliner(&buf, rebase_path_onto(), 0))
+		return error(_("could not read 'onto'"));
+	if (get_oid(buf.buf, &onto_oid)) {
+		strbuf_release(&buf);
+		return error(_("need a HEAD to fixup"));
+	}
+	strbuf_release(&buf);
+
+	fd = open(todo_file, O_RDONLY);
+	if (fd < 0) {
+		return error_errno(_("could not open '%s'"), todo_file);
+	}
+	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
+		close(fd);
+		return error(_("could not read '%s'."), todo_file);
+	}
+	close(fd);
+	if (parse_insn_buffer(todo_list.buf.buf, &todo_list) < 0) {
+		todo_list_release(&todo_list);
+		return -1;
+	}
+
+	for (i = 0; i < todo_list.nr; i++) {
+		struct todo_item *item = todo_list.items + i;
+
+		if (item->command >= TODO_NOOP)
+			continue;
+		if (item->command != TODO_PICK)
+			break;
+		if (parse_commit(item->commit)) {
+			todo_list_release(&todo_list);
+			return error(_("could not parse commit '%s'"),
+				oid_to_hex(&item->commit->object.oid));
+		}
+		if (!item->commit->parents)
+			break; /* root commit */
+		if (item->commit->parents->next)
+			break; /* merge commit */
+		parent_oid = &item->commit->parents->item->object.oid;
+		if (hashcmp(parent_oid->hash, oid->hash))
+			break;
+		oid = &item->commit->object.oid;
+	}
+	if (i > 0) {
+		int offset = i < todo_list.nr ?
+			todo_list.items[i].offset_in_buf : todo_list.buf.len;
+		const char *done_path = rebase_path_done();
+
+		fd = open(done_path, O_CREAT | O_WRONLY | O_APPEND, 0666);
+		if (fd < 0) {
+			error_errno(_("could not open '%s' for writing"),
+				    done_path);
+			todo_list_release(&todo_list);
+			return -1;
+		}
+		if (write_in_full(fd, todo_list.buf.buf, offset) < 0) {
+			error_errno(_("could not write to '%s'"), done_path);
+			todo_list_release(&todo_list);
+			close(fd);
+			return -1;
+		}
+		close(fd);
+
+		fd = open(rebase_path_todo(), O_WRONLY, 0666);
+		if (fd < 0) {
+			error_errno(_("could not open '%s' for writing"),
+				    rebase_path_todo());
+			todo_list_release(&todo_list);
+			return -1;
+		}
+		if (write_in_full(fd, todo_list.buf.buf + offset,
+				todo_list.buf.len - offset) < 0) {
+			error_errno(_("could not write to '%s'"),
+				    rebase_path_todo());
+			close(fd);
+			todo_list_release(&todo_list);
+			return -1;
+		}
+		if (ftruncate(fd, todo_list.buf.len - offset) < 0) {
+			error_errno(_("could not truncate '%s'"),
+				    rebase_path_todo());
+			todo_list_release(&todo_list);
+			close(fd);
+			return -1;
+		}
+		close(fd);
+
+		todo_list.current = i;
+		if (is_fixup(peek_command(&todo_list, 0)))
+			record_in_rewritten(oid, peek_command(&todo_list, 0));
+	}
+
+	todo_list_release(&todo_list);
+	printf("%s\n", oid_to_hex(oid));
+
+	return 0;
+}
+
+struct subject2item_entry {
+	struct hashmap_entry entry;
+	int i;
+	char subject[FLEX_ARRAY];
+};
+
+static int subject2item_cmp(const void *fndata,
+			    const struct subject2item_entry *a,
+			    const struct subject2item_entry *b, const void *key)
+{
+	return key ? strcmp(a->subject, key) : strcmp(a->subject, b->subject);
+}
+
+/*
+ * Rearrange the todo list that has both "pick commit-id msg" and "pick
+ * commit-id fixup!/squash! msg" in it so that the latter is put immediately
+ * after the former, and change "pick" to "fixup"/"squash".
+ *
+ * Note that if the config has specified a custom instruction format, each log
+ * message will have to be retrieved from the commit (as the oneline in the
+ * script cannot be trusted) in order to normalize the autosquash arrangement.
+ */
+int rearrange_squash(void)
+{
+	const char *todo_file = rebase_path_todo();
+	struct todo_list todo_list = TODO_LIST_INIT;
+	struct hashmap subject2item;
+	int res = 0, rearranged = 0, *next, *tail, fd, i;
+	char **subjects;
+
+	fd = open(todo_file, O_RDONLY);
+	if (fd < 0)
+		return error_errno(_("could not open '%s'"), todo_file);
+	if (strbuf_read(&todo_list.buf, fd, 0) < 0) {
+		close(fd);
+		return error(_("could not read '%s'."), todo_file);
+	}
+	close(fd);
+	if (parse_insn_buffer(todo_list.buf.buf, &todo_list) < 0) {
+		todo_list_release(&todo_list);
+		return -1;
+	}
+
+	/*
+	 * The hashmap maps onelines to the respective todo list index.
+	 *
+	 * If any items need to be rearranged, the next[i] value will indicate
+	 * which item was moved directly after the i'th.
+	 *
+	 * In that case, last[i] will indicate the index of the latest item to
+	 * be moved to appear after the i'th.
+	 */
+	hashmap_init(&subject2item, (hashmap_cmp_fn) subject2item_cmp,
+		     NULL, todo_list.nr);
+	ALLOC_ARRAY(next, todo_list.nr);
+	ALLOC_ARRAY(tail, todo_list.nr);
+	ALLOC_ARRAY(subjects, todo_list.nr);
+	for (i = 0; i < todo_list.nr; i++) {
+		struct strbuf buf = STRBUF_INIT;
+		struct todo_item *item = todo_list.items + i;
+		const char *commit_buffer, *subject, *p;
+		size_t subject_len;
+		int i2 = -1;
+		struct subject2item_entry *entry;
+
+		next[i] = tail[i] = -1;
+		if (item->command >= TODO_EXEC) {
+			subjects[i] = NULL;
+			continue;
+		}
+
+		if (is_fixup(item->command)) {
+			todo_list_release(&todo_list);
+			return error(_("the script was already rearranged."));
+		}
+
+		item->commit->util = item;
+
+		parse_commit(item->commit);
+		commit_buffer = get_commit_buffer(item->commit, NULL);
+		find_commit_subject(commit_buffer, &subject);
+		format_subject(&buf, subject, " ");
+		subject = subjects[i] = strbuf_detach(&buf, &subject_len);
+		unuse_commit_buffer(item->commit, commit_buffer);
+		if ((skip_prefix(subject, "fixup! ", &p) ||
+		     skip_prefix(subject, "squash! ", &p))) {
+			struct commit *commit2;
+
+			for (;;) {
+				while (isspace(*p))
+					p++;
+				if (!skip_prefix(p, "fixup! ", &p) &&
+				    !skip_prefix(p, "squash! ", &p))
+					break;
+			}
+
+			if ((entry = hashmap_get_from_hash(&subject2item,
+							   strhash(p), p)))
+				/* found by title */
+				i2 = entry->i;
+			else if (!strchr(p, ' ') &&
+				 (commit2 =
+				  lookup_commit_reference_by_name(p)) &&
+				 commit2->util)
+				/* found by commit name */
+				i2 = (struct todo_item *)commit2->util
+					- todo_list.items;
+			else {
+				/* copy can be a prefix of the commit subject */
+				for (i2 = 0; i2 < i; i2++)
+					if (subjects[i2] &&
+					    starts_with(subjects[i2], p))
+						break;
+				if (i2 == i)
+					i2 = -1;
+			}
+		}
+		if (i2 >= 0) {
+			rearranged = 1;
+			todo_list.items[i].command =
+				starts_with(subject, "fixup!") ?
+				TODO_FIXUP : TODO_SQUASH;
+			if (next[i2] < 0)
+				next[i2] = i;
+			else
+				next[tail[i2]] = i;
+			tail[i2] = i;
+		} else if (!hashmap_get_from_hash(&subject2item,
+						strhash(subject), subject)) {
+			FLEX_ALLOC_MEM(entry, subject, subject, subject_len);
+			entry->i = i;
+			hashmap_entry_init(entry, strhash(entry->subject));
+			hashmap_put(&subject2item, entry);
+		}
+	}
+
+	if (rearranged) {
+		struct strbuf buf = STRBUF_INIT;
+
+		for (i = 0; i < todo_list.nr; i++) {
+			enum todo_command command = todo_list.items[i].command;
+			int cur = i;
+
+			/*
+			 * Initially, all commands are 'pick's. If it is a
+			 * fixup or a squash now, we have rearranged it.
+			 */
+			if (is_fixup(command))
+				continue;
+
+			while (cur >= 0) {
+				int offset = todo_list.items[cur].offset_in_buf;
+				int end_offset = cur + 1 < todo_list.nr ?
+					todo_list.items[cur + 1].offset_in_buf :
+					todo_list.buf.len;
+				char *bol = todo_list.buf.buf + offset;
+				char *eol = todo_list.buf.buf + end_offset;
+
+				/* replace 'pick', by 'fixup' or 'squash' */
+				command = todo_list.items[cur].command;
+				if (is_fixup(command)) {
+					strbuf_addstr(&buf,
+						todo_command_info[command].str);
+					bol += strcspn(bol, " \t");
+				}
+
+				strbuf_add(&buf, bol, eol - bol);
+
+				cur = next[cur];
+			}
+		}
+
+		fd = open(todo_file, O_WRONLY);
+		if (fd < 0)
+			res = error_errno(_("could not open '%s'"), todo_file);
+		else if (write(fd, buf.buf, buf.len) < 0)
+			res = error_errno(_("could not read '%s'."), todo_file);
+		else if (ftruncate(fd, buf.len) < 0)
+			res = error_errno(_("could not finish '%s'"),
+					   todo_file);
+		close(fd);
+		strbuf_release(&buf);
+	}
+
+	free(next);
+	free(tail);
+	for (i = 0; i < todo_list.nr; i++)
+		free(subjects[i]);
+	free(subjects);
+	hashmap_free(&subject2item, 1);
+	todo_list_release(&todo_list);
+
+	return res;
+}