game/scripts/main.gd

@@ -57,6 +57,9 @@ var _save_blocked := false
 var _figure_wait := 0.0
 ## The address a guest is joining, for messages.
 var _joining := ""
+## The host's accepted guests when _process last looked. A new one ends a
+## pause.
+var _known_guests := 0
 
 
 func _ready() -> void:
@@ -233,12 +236,37 @@ func _leave(message: String) -> void:
 	_show_menu(message)
 
 
+## A broken session runs no more ticks. Instead of leaving the others
+## waiting, a host closes its world to guests and a guest leaves.
+func _stop_sharing() -> void:
+	if not session.is_host():
+		_leave(tr("SIMULATION_STOPPED"))
+		return
+	link.link.close()
+	link = null
+	figures.clear()
+	_update_status()
+
+
+## Ends a pause once the host accepted a guest: the guest joins in the next
+## tick, and a paused world would keep it waiting. A connection that has not
+## greeted yet is no guest.
+func _end_pause_for_new_guests() -> void:
+	var guests := session.guest_count()
+	if guests > _known_guests and clock.paused:
+		_set_paused(false)
+	_known_guests = guests
+
+
 func _process(delta: float) -> void:
 	if link != null:
 		for notice in link.pump(delta):
 			_on_notice(notice)
+	if session != null and session.is_broken() and link != null:
+		_stop_sharing()
 	if session == null or not session.is_running() or session.is_broken():
 		return
+	_end_pause_for_new_guests()
 	_update_marker()
 	if Input.is_action_pressed("dig") and not clock.paused:
 		_try_dig()
@@ -257,11 +285,10 @@ func _process(delta: float) -> void:
 
 
 func _on_notice(notice: Dictionary) -> void:
+	# An earlier notice of the same batch may have ended the session.
+	if session == null:
+		return
 	match notice["type"]:
-		"guest_arrived":
-			# Pausing is for playing alone; a guest ends the pause.
-			if clock.paused:
-				_set_paused(false)
 		"world_received":
 			if notice["resync"]:
 				resyncs += 1
@@ -304,7 +331,8 @@ func _unhandled_input(event: InputEvent) -> void:
 	elif event.is_action_pressed("load_game"):
 		_reload()
 	elif event.is_action_pressed("toggle_pause"):
-		if session.is_host() and session.guest_count() == 0:
+		# Ending a pause is always allowed, starting one only alone.
+		if clock.paused or (session.is_host() and session.guest_count() == 0):
 			_set_paused(not clock.paused)
 		else:
 			hud.flash("PAUSE_ONLY_ALONE")

game/tests/test_main.gd

@@ -268,6 +268,34 @@ func test_only_the_host_saves_and_only_alone_one_may_pause_or_load() -> void:
 	_clean_up([host_dir, guest_dir])
 
 
+func test_an_accepted_guest_ends_a_pause_and_a_bare_connection_does_not() -> void:
+	var host_dir := TestFiles.temporary_dir("host")
+	var guest_dir := TestFiles.temporary_dir("guest")
+	var host := _start_host(host_dir)
+	_press(host, "toggle_pause")
+	check(host.clock.paused, "the host pauses while alone")
+
+	# A connection that never greets is no guest.
+	var stranger := NetLink.new()
+	stranger.join("127.0.0.1", host.link.link.local_port())
+	var seen := func() -> bool:
+		stranger.poll(1.0 / 60.0)
+		return host.link.link._peers.size() == 1
+	check(await _wait_until(seen), "the host sees a bare connection")
+	check(host.clock.paused, "which leaves the pause alone")
+
+	var guest := _start_guest(guest_dir, host)
+	check(await _wait_until(_joined.bind(guest)), "a guest joins the paused world")
+	check(not host.clock.paused, "and ends the pause")
+
+	# Should a pause ever meet a guest, the host can still end it.
+	host._set_paused(true)
+	_press(host, "toggle_pause")
+	check(not host.clock.paused, "the host can always end a pause")
+	stranger.close()
+	_clean_up([host_dir, guest_dir])
+
+
 func test_the_host_sees_a_guest_leave() -> void:
 	var host_dir := TestFiles.temporary_dir("host")
 	var guest_dir := TestFiles.temporary_dir("guest")
@@ -295,6 +323,36 @@ func test_a_guest_goes_back_to_the_menu_when_the_host_closes() -> void:
 	_clean_up([host_dir, guest_dir])
 
 
+func test_a_host_that_stops_sharing_lets_its_guests_go() -> void:
+	var host_dir := TestFiles.temporary_dir("host")
+	var guest_dir := TestFiles.temporary_dir("guest")
+	var host := _start_host(host_dir)
+	var guest := _start_guest(guest_dir, host)
+	await _wait_until(_joined.bind(guest))
+	# An internal error of the core cannot be caused from here. For a broken
+	# session, _process calls what this test calls.
+	host._stop_sharing()
+	check(host.link == null, "the host no longer listens")
+	check_eq(host.hud.status_text(), "", "and no longer says that it does")
+	check(await _wait_until(func() -> bool: return guest.session == null), "the guest's session ends")
+	check_eq(guest.menu.status(), tr("HOST_LEFT"), "and the guest learns why")
+	_clean_up([host_dir, guest_dir])
+
+
+func test_a_guest_that_stops_sharing_leaves() -> void:
+	var host_dir := TestFiles.temporary_dir("host")
+	var guest_dir := TestFiles.temporary_dir("guest")
+	var host := _start_host(host_dir)
+	var guest := _start_guest(guest_dir, host)
+	await _wait_until(_joined.bind(guest))
+	# As above, for a guest whose own core stopped.
+	guest._stop_sharing()
+	check(guest.session == null, "the guest's session ends")
+	check_eq(guest.menu.status(), tr("SIMULATION_STOPPED"), "the menu says why")
+	check(await _wait_until(func() -> bool: return host.hud.message() == tr("PLAYER_LEFT") % "Grace"), "the host sees the guest go")
+	_clean_up([host_dir, guest_dir])
+
+
 func test_a_guest_that_is_turned_away_learns_why() -> void:
 	var host_dir := TestFiles.temporary_dir("host")
 	var host := _start_host(host_dir)
@@ -305,6 +363,17 @@ func test_a_guest_that_is_turned_away_learns_why() -> void:
 	_clean_up([host_dir])
 
 
+func test_notices_after_the_end_of_a_session_are_ignored() -> void:
+	var directory := TestFiles.temporary_dir("late")
+	var main := _start_main(directory)
+	# In one batch of notices, an earlier one may have ended the session.
+	main._on_notice({"type": "world_received", "resync": true})
+	main._on_notice({"type": "protocol_error"})
+	check(main.session == null, "no session")
+	check(main.menu.visible, "the menu stays")
+	_clean_up([directory])
+
+
 func test_a_mistyped_address_is_reported() -> void:
 	var directory := TestFiles.temporary_dir("typo")
 	var main := _start_main(directory)