Re-check use of "useLoc" once more.

Fixes:
* On passable-violations useLoc might have been passed as newTo.

Reduce potential for accidental future misuse:
* Call useLoc.setWorld(null) as late as possible.
* Do not reset world of MoveInfo.useLoc in MoveInfo.set.

NCPCore/src/main/java/fr/neatmonster/nocheatplus/checks/blockplace/BlockPlaceListener.java

@@ -134,7 +134,6 @@ public class BlockPlaceListener extends CheckListener {
         if (!cancelled && reach.isEnabled(player) && reach.check(player, block, data, cc)) {
         	cancelled = true;
         }
-        useLoc.setWorld(null);
 
         // Direction check.
         if (!cancelled && direction.isEnabled(player) && direction.check(player, block, blockAgainst, data, cc)) {
@@ -150,6 +149,8 @@ public class BlockPlaceListener extends CheckListener {
         if (cancelled) {
         	event.setCancelled(cancelled);
         }
+        // Cleanup
+        // Reminder(currently unused): useLoc.setWorld(null);
     }
     
     @EventHandler(priority = EventPriority.LOWEST, ignoreCancelled = true)

NCPCore/src/main/java/fr/neatmonster/nocheatplus/checks/fight/Angle.java

@@ -42,11 +42,14 @@ public class Angle extends Check {
         boolean cancel = false;
 
         // Remove the old locations from the map.
-        for (final long time : new TreeMap<Long, Location>(data.angleHits).navigableKeySet())
+        for (final long time : new TreeMap<Long, Location>(data.angleHits).navigableKeySet()) {
-            if (System.currentTimeMillis() - time > 1000L)
+        	if (System.currentTimeMillis() - time > 1000L) {
         		data.angleHits.remove(time);
+        	}
+        }
 
         // Add the new location to the map.
+        // TODO: Alter method to store something less fat.
         data.angleHits.put(System.currentTimeMillis(), player.getLocation()); // This needs to be a copy at present.
 
         // Not enough data to calculate deltas.

NCPCore/src/main/java/fr/neatmonster/nocheatplus/checks/moving/MoveInfo.java

@@ -13,11 +13,12 @@ import fr.neatmonster.nocheatplus.utilities.PlayerLocation;
  *
  */
 public class MoveInfo {
+	
+	/** For temporary use. Might need cloning for passing to external API. Only use after calling MoveInfo.set! */
+    public final Location useLoc = new Location(null, 0, 0, 0);
 	public final BlockCache cache;
     public final PlayerLocation from;
     public final PlayerLocation to;
-    /** For temporary use. Might need cloning for passing to external API. */
-    public final Location useLoc = new Location(null, 0, 0, 0);
     
     public MoveInfo(final MCAccess mcAccess){
     	cache = mcAccess.getBlockCache(null);
@@ -26,26 +27,31 @@ public class MoveInfo {
     }
     
     /**
-     * Demands at least setting from.
+     * Initialize from, and if given to. Note that useLoc is left untouched (!).
      * @param player
-     * @param from
+     * @param from Must not be null.
-     * @param to
+     * @param to Can be null.
      * @param yOnGround
      */
     public final void set(final Player player, final Location from, final Location to, final double yOnGround){
-        this.from.set(from, player, yOnGround);
     	this.cache.setAccess(from.getWorld());
+        this.from.set(from, player, yOnGround);
         this.from.setBlockCache(cache);
         if (to != null){
             this.to.set(to, player, yOnGround);
             this.to.setBlockCache(cache);
         }
-        useLoc.setWorld(null); // Just in case of repeated setting.
+        // Note: using set to reset to by passing null won't work. 
     }
+    
+    /**
+     * Clear caches and remove World references and such. Also resets the world of useLoc.
+     */
     public final void cleanup(){
+    	useLoc.setWorld(null);
         from.cleanup();
         to.cleanup();
         cache.cleanup();
-        useLoc.setWorld(null);
     }
+    
 }

NCPCore/src/main/java/fr/neatmonster/nocheatplus/checks/moving/MovingListener.java

@@ -281,13 +281,14 @@ public class MovingListener extends CheckListener implements TickListener, IRemo
 				// TODO: Add something to guess the best set back location (possibly data.guessSetBack(Location)).
 				target = LocUtil.clone(loc);
 			}
-			useLoc.setWorld(null);
 			if (sfCheck && cc.sfFallDamage && noFall.isEnabled(player)) {
 				// Check if to deal damage.
 				double y = loc.getY();
 				if (data.hasSetBack()) y = Math.min(y, data.getSetBackY());
 				noFall.checkDamage(player, data, y);
 			}
+			// Cleanup
+			useLoc.setWorld(null);
 			// Teleport.
 			data.prepareSetBack(target); // Should be enough. | new Location(target.getWorld(), target.getX(), target.getY(), target.getZ(), target.getYaw(), target.getPitch());
 			player.teleport(target, TeleportCause.PLUGIN);// TODO: schedule / other measures ?
@@ -418,8 +419,12 @@ public class MovingListener extends CheckListener implements TickListener, IRemo
 		// TODO: Order this to above "early return"?
         // Set up data / caching.
         final MoveInfo moveInfo;
-        if (parkedInfo.isEmpty()) moveInfo = new MoveInfo(mcAccess);
+        if (parkedInfo.isEmpty()) {
-        else moveInfo = parkedInfo.remove(parkedInfo.size() - 1);
+        	moveInfo = new MoveInfo(mcAccess);
+        }
+        else {
+        	moveInfo = parkedInfo.remove(parkedInfo.size() - 1);
+        }
         final MovingConfig cc = MovingConfig.getConfig(player);
         moveInfo.set(player, from, to, cc.yOnGround);
         // TODO: Data resetting above ?
@@ -1123,8 +1128,12 @@ public class MovingListener extends CheckListener implements TickListener, IRemo
         boolean allowReset = true;
         if (!data.noFallSkipAirCheck) {
         	final MoveInfo moveInfo;
-        	if (parkedInfo.isEmpty()) moveInfo = new MoveInfo(mcAccess);
+        	if (parkedInfo.isEmpty()) {
-            else moveInfo = parkedInfo.remove(parkedInfo.size() - 1);
+        		moveInfo = new MoveInfo(mcAccess);
+        	}
+            else {
+            	moveInfo = parkedInfo.remove(parkedInfo.size() - 1);
+            }
         	moveInfo.set(player, loc, null, cc.noFallyOnGround);
         	// NOTE: No isIllegal check here.
         	final PlayerLocation pLoc = moveInfo.from;
@@ -1150,7 +1159,6 @@ public class MovingListener extends CheckListener implements TickListener, IRemo
         	moveInfo.cleanup();
         	parkedInfo.add(moveInfo);
         }
-        useLoc.setWorld(null);
         final float fallDistance = player.getFallDistance();
         final double damage = BridgeHealth.getDamage(event);
         final float yDiff = (float) (data.noFallMaxY - loc.getY());
@@ -1183,6 +1191,8 @@ public class MovingListener extends CheckListener implements TickListener, IRemo
         	}
         }
         // Entity fall-distance should be reset elsewhere.
+        // Cleanup.
+        useLoc.setWorld(null);
     }
     
 	/**
@@ -1468,8 +1478,12 @@ public class MovingListener extends CheckListener implements TickListener, IRemo
 			return;
 		}
 		final MoveInfo info;
-		if (parkedInfo.isEmpty()) info = new MoveInfo(mcAccess);
+		if (parkedInfo.isEmpty()) {
-		else info = parkedInfo.remove(parkedInfo.size() - 1);
+			info = new MoveInfo(mcAccess);
+		}
+		else {
+			info = parkedInfo.remove(parkedInfo.size() - 1);
+		}
 		for (final String playerName : hoverTicks) {
 			// TODO: put players into the set (+- one tick would not matter ?)
 			// TODO: might add an online flag to data !
@@ -1546,6 +1560,7 @@ public class MovingListener extends CheckListener implements TickListener, IRemo
 		// Check if player is on ground.
 		final Location loc = player.getLocation(useLoc); // useLoc.setWorld(null) is done in onTick.
 		info.set(player, loc, null, cc.yOnGround);
+		// (Could use useLoc of MoveInfo here. Note orderm though.)
 		final boolean res;
 		// TODO: Collect flags, more margin ?
 		final int loaded = info.from.ensureChunksLoaded();

NCPCore/src/main/java/fr/neatmonster/nocheatplus/checks/moving/Passable.java

@@ -136,7 +136,7 @@ public class Passable extends Check {
 					System.out.println(player.getName() + " Using set-back location for passable.");
 				}
 			} else if (cc.debug) {
-				System.out.println(player.getName() + " Ignorng set-back for passable.");
+				System.out.println(player.getName() + " Ignoring set-back for passable.");
 			}
 		}
 
@@ -155,7 +155,8 @@ public class Passable extends Check {
 			// TODO: Consider another set back position for this, also keeping track of players moving around in blocks.
 			final Location newTo;
 			if (loc != null) {
-				newTo = loc;
+				// Ensure the given location is cloned.
+				newTo = LocUtil.clone(loc);
 			} else {
 				newTo = from.getLocation();
 				if (cc.debug) {