From 7049b78624949a071e97bca5d87112941d982e49 Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 9 Mar 2016 17:12:20 +0100
Subject: [PATCH] sequencer (rebase -i): allow continuing with staged changes

When an interactive rebase is interrupted, the user may stage changes
before continuing, and we need to commit those changes in that case.

Please note that the nested "if" added to the sequencer_continue() is
not combined into a single "if" because it will be extended with an
"else" clause in a later patch in this patch series.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 sequencer.c | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/sequencer.c b/sequencer.c
index 1dda1b78cc..7dd7ea53e0 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -1873,6 +1873,42 @@ static int continue_single_pick(void)
 	return run_command_v_opt(argv, RUN_GIT_CMD);
 }
 
+static int commit_staged_changes(struct replay_opts *opts)
+{
+	int amend = 0;
+
+	if (has_unstaged_changes(1))
+		return error(_("cannot rebase: You have unstaged changes."));
+	if (!has_uncommitted_changes(0))
+		return 0;
+
+	if (file_exists(rebase_path_amend())) {
+		struct strbuf rev = STRBUF_INIT;
+		unsigned char head[20], to_amend[20];
+
+		if (get_sha1("HEAD", head))
+			return error(_("cannot amend non-existing commit"));
+		if (!read_oneliner(&rev, rebase_path_amend(), 0))
+			return error(_("invalid file: '%s'"), rebase_path_amend());
+		if (get_sha1_hex(rev.buf, to_amend))
+			return error(_("invalid contents: '%s'"),
+				rebase_path_amend());
+		if (hashcmp(head, to_amend))
+			return error(_("\nYou have uncommitted changes in your "
+				       "working tree. Please, commit them\n"
+				       "first and then run 'git rebase "
+				       "--continue' again."));
+
+		strbuf_release(&rev);
+		amend = 1;
+	}
+
+	if (run_git_commit(rebase_path_message(), opts, 1, 1, amend, 0))
+		return error(_("could not commit staged changes."));
+	unlink(rebase_path_amend());
+	return 0;
+}
+
 int sequencer_continue(struct replay_opts *opts)
 {
 	struct todo_list todo_list = TODO_LIST_INIT;
@@ -1881,6 +1917,10 @@ int sequencer_continue(struct replay_opts *opts)
 	if (read_and_refresh_cache(opts))
 		return -1;
 
+	if (is_rebase_i(opts)) {
+		if (commit_staged_changes(opts))
+			return -1;
+	}
 	if (!file_exists(get_todo_path(opts)))
 		return continue_single_pick();
 	if (read_populate_opts(opts))