defer movement propagation and assembly to postprocessing

src/main/java/baritone/pathing/calc/Path.java

@@ -86,11 +86,11 @@ class Path implements IPath {
             throw new IllegalStateException();
         }
         PathNode current = end;
-        LinkedList<BetterBlockPos> tempPath = new LinkedList<>(); // Repeatedly inserting to the beginning of an arraylist is O(n^2)
+        LinkedList<BetterBlockPos> tempPath = new LinkedList<>();
-        LinkedList<Movement> tempMovements = new LinkedList<>(); // Instead, do it into a linked list, then convert at the end
+        // Repeatedly inserting to the beginning of an arraylist is O(n^2)
+        // Instead, do it into a linked list, then convert at the end
         while (!current.equals(start)) {
             tempPath.addFirst(new BetterBlockPos(current.x, current.y, current.z));
-            tempMovements.addFirst(runBackwards(current.previous, current));
             current = current.previous;
         }
         tempPath.addFirst(this.start);
@@ -98,20 +98,6 @@ class Path implements IPath {
         // inserting into a LinkedList<E> keeps track of length, then when we addall (which calls .toArray) it's able
         // to performantly do that conversion since it knows the length.
         path.addAll(tempPath);
-        movements.addAll(tempMovements);
-    }
-
-    private static Movement runBackwards(PathNode src0, PathNode dest0) { // TODO this is horrifying
-        BetterBlockPos src = new BetterBlockPos(src0.x, src0.y, src0.z);
-        BetterBlockPos dest = new BetterBlockPos(dest0.x, dest0.y, dest0.z);
-        for (Moves moves : Moves.values()) {
-            Movement move = moves.apply0(src);
-            if (move.getDest().equals(dest)) {
-                return move;
-            }
-        }
-        // leave this as IllegalStateException; it's caught in AbstractNodeCostSearch
-        throw new IllegalStateException("Movement became impossible during calculation " + src + " " + dest + " " + dest.subtract(src));
     }
 
     /**
@@ -140,12 +126,33 @@ class Path implements IPath {
         }
     }
 
+    private void assembleMovements() {
+        if (path.isEmpty() || !movements.isEmpty()) {
+            throw new IllegalStateException();
+        }
+        for (int i = 0; i < path.size() - 1; i++) {
+            movements.add(runBackwards(path.get(i), path.get(i + 1)));
+        }
+    }
+
+    private static Movement runBackwards(BetterBlockPos src, BetterBlockPos dest) { // TODO this is horrifying
+        for (Moves moves : Moves.values()) {
+            Movement move = moves.apply0(src);
+            if (move.getDest().equals(dest)) {
+                return move;
+            }
+        }
+        // leave this as IllegalStateException; it's caught in AbstractNodeCostSearch
+        throw new IllegalStateException("Movement became impossible during calculation " + src + " " + dest + " " + dest.subtract(src));
+    }
+
     @Override
     public void postprocess() {
         if (verified) {
             throw new IllegalStateException();
         }
         verified = true;
+        assembleMovements();
         // more post processing here
         movements.forEach(Movement::checkLoadedChunk);
         sanityCheck();