New undo functions.

Can handle supply queries during replay without crashing on clear undo.

1 files changed, 24 insertions, 27 deletions

diff --git a/rules.js b/rules.js
index b7de0e4..8399cad 100644
--- a/rules.js
+++ b/rules.js
@@ -9595,34 +9595,38 @@ exports.setup = function (seed, scenario, options) {
 // ACTION HANDLERS
 
 function clear_undo() {
-	if (game.undo.length > 0)
+	if (game.undo && game.undo.length > 0)
 		game.undo.length = 0
 }
 
 function push_undo() {
-	let copy = {}
-	for (let k in game) {
-		let v = game[k]
-		if (k === "undo") continue
-		else if (k === "log") v = v.length
-		else if (k === "retro_foul_weather") v = 1
-		else if (typeof v === "object" && v !== null) v = object_copy(v)
-		copy[k] = v
+	if (game.undo) {
+		let copy = {}
+		for (let k in game) {
+			let v = game[k]
+			if (k === "undo") continue
+			else if (k === "log") v = v.length
+			else if (k === "retro_foul_weather") v = 1
+			else if (typeof v === "object" && v !== null) v = object_copy(v)
+			copy[k] = v
+		}
+		game.undo.push(copy)
 	}
-	game.undo.push(copy)
 }
 
 function pop_undo() {
-	let save_log = game.log
-	let save_undo = game.undo
-	let save_retro_fw = game.retro_foul_weather
-	game = save_undo.pop()
-	save_log.length = game.log
-	game.log = save_log
-	game.undo = save_undo
-	if (game.retro_foul_weather)
-		game.retro_foul_weather = save_retro_fw
-	update_active_aliases()
+	if (game.undo) {
+		let save_log = game.log
+		let save_undo = game.undo
+		let save_retro_fw = game.retro_foul_weather
+		game = save_undo.pop()
+		save_log.length = game.log
+		game.log = save_log
+		game.undo = save_undo
+		if (game.retro_foul_weather)
+			game.retro_foul_weather = save_retro_fw
+		update_active_aliases()
+	}
 }
 
 function gen_action_undo() {
@@ -9715,13 +9719,6 @@ exports.query = function (state, current, q) {
 	return null
 }
 
-exports.is_checkpoint = function (a, b) {
-	let x = b.log[b.log.length-2]
-	if (x === ".h2 Britain") return true
-	if (x === ".h2 France") return true
-	return false
-}
-
 function inactive_prompt(name, who, where) {
 	view.prompt = `Waiting for ${game.active} \u2014 ${name}...`
 	if (who)