[PATCH v2 2/2] fix cherry-pick/revert status after commit

[Phillip Wood <phillip.wood123@gmail.com>]

From: Phillip Wood <phillip.wood@dunelm.org.uk>

If the user commits a conflict resolution using `git commit` in the
middle of a sequence of cherry-picks/reverts then `git status` missed
the fact that a cherry-pick/revert is still in progress.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
---
 sequencer.c            | 35 +++++++++++++++++++++++++++++++++++
 sequencer.h            |  2 ++
 t/t7512-status-help.sh | 36 ++++++++++++++++++++++++++++++++++++
 wt-status.c            | 39 ++++++++++++++++++++++++++++++++++-----
 4 files changed, 107 insertions(+), 5 deletions(-)

diff --git a/sequencer.c b/sequencer.c
index 7c7b8a07c4..c6a9a35422 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -2142,6 +2142,41 @@ 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, 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;
+}
+
 static int parse_insn_buffer(struct repository *r, char *buf,
 			     struct todo_list *todo_list)
 {
diff --git a/sequencer.h b/sequencer.h
index 6c7cf8d72f..c4b79165d3 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -145,3 +145,5 @@ void parse_strategy_opts(struct replay_opts *opts, char *raw_opts);
 int write_basic_state(struct replay_opts *opts, const char *head_name,
 		      const char *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);
diff --git a/t/t7512-status-help.sh b/t/t7512-status-help.sh
index 458608cc1e..c1eb72555d 100755
--- a/t/t7512-status-help.sh
+++ b/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 &&
diff --git a/wt-status.c b/wt-status.c
index 1f564b12d2..1dbb4d949c 100644
--- a/wt-status.c
+++ b/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";
@@ -1369,12 +1370,22 @@ 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\")"));
@@ -1387,12 +1398,21 @@ 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\")"));
@@ -1563,6 +1583,7 @@ 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);
@@ -1580,7 +1601,15 @@ 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);
 }
-- 
2.21.0