sequencer (rebase -i): copy commit notes at end

This fixes t3404.50.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

sequencer.c

@@ -92,6 +92,14 @@ static GIT_PATH_FUNC(git_path_rebase_amend, "rebase-merge/amend")
  * the long commit name of the corresponding patch.
  */
 static GIT_PATH_FUNC(stopped_sha, "rebase-merge/stopped-sha")
+/*
+ * For the post-rewrite hook, we make a list of rewritten commits and
+ * their new sha1s.  The rewritten-pending list keeps the sha1s of
+ * commits that have been processed, but not committed yet,
+ * e.g. because they are waiting for a 'squash' command.
+ */
+static GIT_PATH_FUNC(rewritten_list, "rebase-merge/rewritten-list")
+static GIT_PATH_FUNC(rewritten_pending, "rebase-merge/rewritten-pending")
 /*
  * The following files are written by git-rebase just after parsing the
  * command-line (and are only consumed, not modified, by the sequencer).
@@ -799,6 +807,43 @@ static int update_squash_messages(enum todo_command command,
 	return 0;
 }
 
+static void flush_rewritten_pending(void) {
+	struct strbuf buf = STRBUF_INIT;
+	unsigned char newsha1[20];
+	FILE *out;
+
+	if (strbuf_read_file(&buf, rewritten_pending(), 82) > 0 &&
+			!get_sha1("HEAD", newsha1) &&
+			(out = fopen(rewritten_list(), "a"))) {
+		char *bol = buf.buf, *eol;
+
+		while (*bol) {
+			eol = strchrnul(bol, '\n');
+			fprintf(out, "%.*s %s\n", (int)(eol - bol),
+					bol, sha1_to_hex(newsha1));
+			if (!*eol)
+				break;
+			bol = eol + 1;
+		}
+		fclose(out);
+		unlink(rewritten_pending());
+	}
+}
+
+static void record_in_rewritten(struct object_id *oid,
+		enum todo_command next_command) {
+	FILE *out = fopen(rewritten_pending(), "a");
+
+	if (!out)
+		return;
+
+	fprintf(out, "%s\n", oid_to_hex(oid));
+	fclose(out);
+
+	if (!is_fixup(next_command))
+		flush_rewritten_pending();
+}
+
 static int do_pick_commit(enum todo_command command, struct commit *commit,
 		struct replay_opts *opts, int final_fixup)
 {
@@ -1554,6 +1599,17 @@ static int is_final_fixup(struct todo_list *todo_list)
 	return 1;
 }
 
+static enum todo_command peek_command(struct todo_list *todo_list, int offset)
+{
+	int i;
+
+	for (i = todo_list->current + offset; i < todo_list->nr; i++)
+		if (todo_list->items[i].command != TODO_NOOP)
+			return todo_list->items[i].command;
+
+	return -1;
+}
+
 static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
 {
 	int res = 0;
@@ -1587,6 +1643,9 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
 						item->arg_len, item->arg);
 				return error_with_patch(commit, opts, res);
 			}
+			if (IS_REBASE_I() && !res)
+				record_in_rewritten(&item->commit->object.oid,
+					peek_command(todo_list, 1));
 			if (res && is_fixup(item->command))
 				return error_failed_squash(item->commit, opts,
 					item->arg_len, item->arg);
@@ -1611,6 +1670,7 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
 
 	if (IS_REBASE_I()) {
 		struct strbuf head_ref = STRBUF_INIT, buf = STRBUF_INIT;
+		struct stat st;
 
 		/* Stopped in the middle, as planned? */
 		if (todo_list->current < todo_list->nr)
@@ -1656,6 +1716,19 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
 			run_command_v_opt(argv, RUN_GIT_CMD);
 			strbuf_reset(&buf);
 		}
+		flush_rewritten_pending();
+		if (!stat(rewritten_list(), &st) && st.st_size > 0) {
+			struct child_process child = CHILD_PROCESS_INIT;
+
+			child.in = open(rewritten_list(), O_RDONLY);
+			child.git_cmd = 1;
+			argv_array_push(&child.args, "notes");
+			argv_array_push(&child.args, "copy");
+			argv_array_push(&child.args, "--for-rewrite=rebase");
+			/* we don't care if this copying failed */
+			run_command(&child);
+		}
+
 		strbuf_release(&buf);
 		strbuf_release(&head_ref);
 	}