Merge pull request #139 from BeGj/fix/click-outside-map-for-findWarshipsNearCell

handle findWarshipsNearCell (unhandled exception) when clicking outside the map

src/client/graphics/layers/UnitLayer.ts

@@ -82,6 +82,10 @@ export class UnitLayer implements Layer {
    * @returns Array of player's warships in range, sorted by distance (closest first)
    */
   private findWarshipsNearCell(cell: { x: number; y: number }): UnitView[] {
+    if (!this.game.isValidCoord(cell.x, cell.y)) {
+      // The cell coordinate were invalid (user probably clicked outside the map), therefore no warships can be found
+      return [];
+    }
     const clickRef = this.game.ref(cell.x, cell.y);
 
     // Make sure we have the current player