(svn r13002) -Fix (r13001): [autoreplace] previous fix broke updating of a pointer to the front vehicle in certain cases

  Now it's updated when it's the front vehicle and it's every time it's the front vehicle and only if it's the front vehicle (nomatter if the replacement works or not)

1 files changed, 6 insertions, 2 deletions

diff --git a/src/autoreplace_cmd.cpp b/src/autoreplace_cmd.cpp
index 8b9ce5d46..fb5ad11f9 100644
--- a/src/autoreplace_cmd.cpp
+++ b/src/autoreplace_cmd.cpp
@@ -427,10 +427,14 @@ CommandCost MaybeReplaceVehicle(Vehicle *v, uint32 flags, bool display_costs)
 				/* We are going to try to replace a vehicle but we don't have any backup so we will make one. */
 				backup.Backup(v, p);
 			}
-			/* Now replace the vehicle */
+			/* Now replace the vehicle.
+			 * First we need to cache if it's the front vehicle as we need to update the v pointer if it is.
+			 * If the replacement fails then we can't trust the data in the vehicle hence the reason to cache the result. */
+			bool IsFront = w->type != VEH_TRAIN || w->u.rail.first_engine == INVALID_ENGINE;
+
 			cost.AddCost(ReplaceVehicle(&w, DC_EXEC, cost.GetCost(), p, new_engine));
 
-			if (CmdSucceeded(cost) && (w->type != VEH_TRAIN || w->u.rail.first_engine == INVALID_ENGINE)) {
+			if (IsFront) {
 				/* now we bought a new engine and sold the old one. We need to fix the
 				 * pointers in order to avoid pointing to the old one for trains: these
 				 * pointers should point to the front engine and not the cars