Merge branch 'pw/clean-sequencer-state-upon-final-commit'

"git chery-pick" (and "revert" that shares the same runtime engine)
that deals with multiple commits got confused when the final step
gets stopped with a conflict and the user concluded the sequence
with "git commit".  Attempt to fix it by cleaning up the state
files used by these commands in such a situation.

* pw/clean-sequencer-state-upon-final-commit:
  fix cherry-pick/revert status after commit
  commit/reset: try to clean up sequencer state

branch.c

@@ -5,6 +5,7 @@
 #include "refs.h"
 #include "refspec.h"
 #include "remote.h"
+#include "sequencer.h"
 #include "commit.h"
 #include "worktree.h"
 
@@ -339,8 +340,7 @@ void create_branch(struct repository *r,
 
 void remove_branch_state(struct repository *r)
 {
-	unlink(git_path_cherry_pick_head(r));
-	unlink(git_path_revert_head(r));
+	sequencer_post_commit_cleanup(r);
 	unlink(git_path_merge_head(r));
 	unlink(git_path_merge_rr(r));
 	unlink(git_path_merge_msg(r));

builtin/commit.c

@@ -1658,8 +1658,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		die("%s", err.buf);
 	}
 
-	unlink(git_path_cherry_pick_head(the_repository));
-	unlink(git_path_revert_head(the_repository));
+	sequencer_post_commit_cleanup(the_repository);
 	unlink(git_path_merge_head(the_repository));
 	unlink(git_path_merge_msg(the_repository));
 	unlink(git_path_merge_mode(the_repository));

sequencer.c

@@ -2168,6 +2168,41 @@ static int parse_insn_line(struct repository *r, struct todo_item *item,
 	return !item->commit;
 }
 
+int sequencer_get_last_command(struct repository *r, enum replay_action *action)
+{
+	struct todo_item item;
+	char *eol;
+	const char *todo_file;
+	struct strbuf buf = STRBUF_INIT;
+	int ret = -1;
+
+	todo_file = git_path_todo_file();
+	if (strbuf_read_file(&buf, todo_file, 0) < 0) {
+		if (errno == ENOENT)
+			return -1;
+		else
+			return error_errno("unable to open '%s'", todo_file);
+	}
+	eol = strchrnul(buf.buf, '\n');
+	if (buf.buf != eol && eol[-1] == '\r')
+		eol--; /* strip Carriage Return */
+	if (parse_insn_line(r, &item, buf.buf, buf.buf, eol))
+		goto fail;
+	if (item.command == TODO_PICK)
+		*action = REPLAY_PICK;
+	else if (item.command == TODO_REVERT)
+		*action = REPLAY_REVERT;
+	else
+		goto fail;
+
+	ret = 0;
+
+ fail:
+	strbuf_release(&buf);
+
+	return ret;
+}
+
 int todo_list_parse_insn_buffer(struct repository *r, char *buf,
 				struct todo_list *todo_list)
 {
@@ -2251,6 +2286,57 @@ static ssize_t strbuf_read_file_or_whine(struct strbuf *sb, const char *path)
 	return len;
 }
 
+static int have_finished_the_last_pick(void)
+{
+	struct strbuf buf = STRBUF_INIT;
+	const char *eol;
+	const char *todo_path = git_path_todo_file();
+	int ret = 0;
+
+	if (strbuf_read_file(&buf, todo_path, 0) < 0) {
+		if (errno == ENOENT) {
+			return 0;
+		} else {
+			error_errno("unable to open '%s'", todo_path);
+			return 0;
+		}
+	}
+	/* If there is only one line then we are done */
+	eol = strchr(buf.buf, '\n');
+	if (!eol || !eol[1])
+		ret = 1;
+
+	strbuf_release(&buf);
+
+	return ret;
+}
+
+void sequencer_post_commit_cleanup(struct repository *r)
+{
+	struct replay_opts opts = REPLAY_OPTS_INIT;
+	int need_cleanup = 0;
+
+	if (file_exists(git_path_cherry_pick_head(r))) {
+		unlink(git_path_cherry_pick_head(r));
+		opts.action = REPLAY_PICK;
+		need_cleanup = 1;
+	}
+
+	if (file_exists(git_path_revert_head(r))) {
+		unlink(git_path_revert_head(r));
+		opts.action = REPLAY_REVERT;
+		need_cleanup = 1;
+	}
+
+	if (!need_cleanup)
+		return;
+
+	if (!have_finished_the_last_pick())
+		return;
+
+	sequencer_remove_state(&opts);
+}
+
 static int read_populate_todo(struct repository *r,
 			      struct todo_list *todo_list,
 			      struct replay_opts *opts)

sequencer.h

@@ -200,3 +200,6 @@ int read_author_script(const char *path, char **name, char **email, char **date,
 void parse_strategy_opts(struct replay_opts *opts, char *raw_opts);
 int write_basic_state(struct replay_opts *opts, const char *head_name,
 		      struct commit *onto, const char *orig_head);
+void sequencer_post_commit_cleanup(struct repository *r);
+int sequencer_get_last_command(struct repository* r,
+			       enum replay_action *action);

t/t3507-cherry-pick-conflict.sh

@@ -161,6 +161,25 @@ test_expect_success 'successful commit clears CHERRY_PICK_HEAD' '
 
 	test_must_fail git rev-parse --verify CHERRY_PICK_HEAD
 '
+test_expect_success 'successful final commit clears cherry-pick state' '
+	pristine_detach initial &&
+
+	test_must_fail git cherry-pick base picked-signed &&
+	echo resolved >foo &&
+	test_path_is_file .git/sequencer/todo &&
+	git commit -a &&
+	test_must_fail test_path_exists .git/sequencer
+'
+
+test_expect_success 'reset after final pick clears cherry-pick state' '
+	pristine_detach initial &&
+
+	test_must_fail git cherry-pick base picked-signed &&
+	echo resolved >foo &&
+	test_path_is_file .git/sequencer/todo &&
+	git reset &&
+	test_must_fail test_path_exists .git/sequencer
+'
 
 test_expect_success 'failed cherry-pick produces dirty index' '
 	pristine_detach initial &&
@@ -361,6 +380,26 @@ test_expect_success 'failed commit does not clear REVERT_HEAD' '
 	test_cmp_rev picked REVERT_HEAD
 '
 
+test_expect_success 'successful final commit clears revert state' '
+       pristine_detach picked-signed &&
+
+       test_must_fail git revert picked-signed base &&
+       echo resolved >foo &&
+       test_path_is_file .git/sequencer/todo &&
+       git commit -a &&
+       test_must_fail test_path_exists .git/sequencer
+'
+
+test_expect_success 'reset after final pick clears revert state' '
+       pristine_detach picked-signed &&
+
+       test_must_fail git revert picked-signed base &&
+       echo resolved >foo &&
+       test_path_is_file .git/sequencer/todo &&
+       git reset &&
+       test_must_fail test_path_exists .git/sequencer
+'
+
 test_expect_success 'revert conflict, diff3 -m style' '
 	pristine_detach initial &&
 	git config merge.conflictstyle diff3 &&

t/t7512-status-help.sh

@@ -780,6 +780,24 @@ EOF
 	test_i18ncmp expected actual
 '
 
+test_expect_success 'status when cherry-picking after committing conflict resolution' '
+	git reset --hard cherry_branch &&
+	test_when_finished "git cherry-pick --abort" &&
+	test_must_fail git cherry-pick cherry_branch_second one_cherry &&
+	echo end >main.txt &&
+	git commit -a &&
+	cat >expected <<EOF &&
+On branch cherry_branch
+Cherry-pick currently in progress.
+  (run "git cherry-pick --continue" to continue)
+  (use "git cherry-pick --abort" to cancel the cherry-pick operation)
+
+nothing to commit (use -u to show untracked files)
+EOF
+	git status --untracked-files=no >actual &&
+	test_i18ncmp expected actual
+'
+
 test_expect_success 'status showing detached at and from a tag' '
 	test_commit atag tagging &&
 	git checkout atag &&
@@ -857,6 +875,24 @@ EOF
 	test_i18ncmp expected actual
 '
 
+test_expect_success 'status while reverting after committing conflict resolution' '
+	test_when_finished "git revert --abort" &&
+	git reset --hard new &&
+	test_must_fail git revert old new &&
+	echo reverted >to-revert.txt &&
+	git commit -a &&
+	cat >expected <<EOF &&
+On branch master
+Revert currently in progress.
+  (run "git revert --continue" to continue)
+  (use "git revert --abort" to cancel the revert operation)
+
+nothing to commit (use -u to show untracked files)
+EOF
+	git status --untracked-files=no >actual &&
+	test_i18ncmp expected actual
+'
+
 test_expect_success 'prepare for different number of commits rebased' '
 	git reset --hard master &&
 	git checkout -b several_commits &&

wt-status.c

@@ -17,6 +17,7 @@
 #include "utf8.h"
 #include "worktree.h"
 #include "lockfile.h"
+#include "sequencer.h"
 
 static const char cut_line[] =
 "------------------------ >8 ------------------------\n";
@@ -1386,12 +1387,22 @@ static void show_rebase_in_progress(struct wt_status *s,
 static void show_cherry_pick_in_progress(struct wt_status *s,
 					 const char *color)
 {
-	status_printf_ln(s, color, _("You are currently cherry-picking commit %s."),
-			find_unique_abbrev(&s->state.cherry_pick_head_oid, DEFAULT_ABBREV));
+	if (is_null_oid(&s->state.cherry_pick_head_oid))
+		status_printf_ln(s, color,
+			_("Cherry-pick currently in progress."));
+	else
+		status_printf_ln(s, color,
+			_("You are currently cherry-picking commit %s."),
+			find_unique_abbrev(&s->state.cherry_pick_head_oid,
+					   DEFAULT_ABBREV));
+
 	if (s->hints) {
 		if (has_unmerged(s))
 			status_printf_ln(s, color,
 				_("  (fix conflicts and run \"git cherry-pick --continue\")"));
+		else if (is_null_oid(&s->state.cherry_pick_head_oid))
+			status_printf_ln(s, color,
+				_("  (run \"git cherry-pick --continue\" to continue)"));
 		else
 			status_printf_ln(s, color,
 				_("  (all conflicts fixed: run \"git cherry-pick --continue\")"));
@@ -1404,12 +1415,21 @@ static void show_cherry_pick_in_progress(struct wt_status *s,
 static void show_revert_in_progress(struct wt_status *s,
 				    const char *color)
 {
-	status_printf_ln(s, color, _("You are currently reverting commit %s."),
-			 find_unique_abbrev(&s->state.revert_head_oid, DEFAULT_ABBREV));
+	if (is_null_oid(&s->state.revert_head_oid))
+		status_printf_ln(s, color,
+			_("Revert currently in progress."));
+	else
+		status_printf_ln(s, color,
+			_("You are currently reverting commit %s."),
+			find_unique_abbrev(&s->state.revert_head_oid,
+					   DEFAULT_ABBREV));
 	if (s->hints) {
 		if (has_unmerged(s))
 			status_printf_ln(s, color,
 				_("  (fix conflicts and run \"git revert --continue\")"));
+		else if (is_null_oid(&s->state.revert_head_oid))
+			status_printf_ln(s, color,
+				_("  (run \"git revert --continue\" to continue)"));
 		else
 			status_printf_ln(s, color,
 				_("  (all conflicts fixed: run \"git revert --continue\")"));
@@ -1580,6 +1600,7 @@ void wt_status_get_state(struct repository *r,
 {
 	struct stat st;
 	struct object_id oid;
+	enum replay_action action;
 
 	if (!stat(git_path_merge_head(r), &st)) {
 		wt_status_check_rebase(NULL, state);
@@ -1597,7 +1618,15 @@ void wt_status_get_state(struct repository *r,
 		state->revert_in_progress = 1;
 		oidcpy(&state->revert_head_oid, &oid);
 	}
-
+	if (!sequencer_get_last_command(r, &action)) {
+		if (action == REPLAY_PICK) {
+			state->cherry_pick_in_progress = 1;
+			oidcpy(&state->cherry_pick_head_oid, &null_oid);
+		} else {
+			state->revert_in_progress = 1;
+			oidcpy(&state->revert_head_oid, &null_oid);
+		}
+	}
 	if (get_detached_from)
 		wt_status_get_detached_from(r, state);
 }