simplified example of shape order issue

sample/Main.hx

@@ -46,7 +46,7 @@ class Main extends BaseApp {
 
     // Set up our Sample States
     sample_states = [
-      PolygonState, StackingState, MultiShapeState, ShapesState, GroupsState, StaticState, LinecastState, Linecast2State, TileMapState, TileMapState2,
+      ListenerState, PolygonState, StackingState, MultiShapeState, ShapesState, GroupsState, StaticState, LinecastState, Linecast2State, TileMapState, TileMapState2,
       BezierState, VerletState
     ];
     index = 0;

sample/state/ListenerState.hx

@@ -0,0 +1,81 @@
+package state;
+
+import echo.data.Options.ListenerOptions;
+import echo.Material;
+import echo.Body;
+import echo.World;
+import util.Random;
+
+class ListenerState extends BaseState {
+
+  override public function enter(world:World) {
+    Main.instance.state_text.text = "Sample: Collision Listener";
+
+    // Create a material for all the shapes to share
+    var material:Material = {elasticity: 0.7};
+
+    var bodyA = new Body({
+        x: Random.range(60, world.width - 60),
+        y: Random.range(0, world.height / 2),
+        rotation: Random.range(0, 360),
+        material: material,
+        shapes: [
+			{
+				type: POLYGON,
+				radius: Random.range(16, 32),
+				width: Random.range(16, 48),
+				height: Random.range(16, 48),
+				sides: Random.range_int(3, 8),
+				offset_y: -10,
+			},
+			{
+				type: POLYGON,
+				radius: Random.range(16, 32),
+				width: Random.range(16, 48),
+				height: Random.range(16, 48),
+				sides: Random.range_int(3, 8),
+				offset_y: 10,
+			}
+		]
+      });
+    world.add(bodyA);
+
+    // Add a Physics body at the bottom of the screen for the other Physics Bodies to stack on top of
+    // This body has a mass of 0, so it acts as an immovable object
+	var bodyB = new Body({
+		mass: STATIC,
+		x: world.width / 5,
+		y: world.height - 40,
+		material: material,
+		rotation: 5,
+		shape: {
+		  type: RECT,
+		  width: world.width,
+		  height: 20
+		}
+	  });
+    world.add(bodyB);
+
+    var dbgOpts:ListenerOptions = {
+      enter: (a, b, data) -> {
+		trace('bodyA == listener `a`: ${bodyA == a}');
+		trace('bodyA shape == data `shape a`: ${bodyA.shape == data[0].sa}');
+		trace('bodyB == listener `b`: ${bodyB == b}');
+		trace('bodyB shape == data `shape b`: ${bodyB.shape == data[0].sb}');
+      },
+    };
+
+    // Create a listener for collisions between the Physics Bodies
+    world.listen(bodyA, bodyB, dbgOpts);
+  }
+
+  override function step(world:World, dt:Float) {
+    // Reset any off-screen Bodies
+    world.for_each((member) -> {
+      if (offscreen(member, world)) {
+        member.velocity.set(0, 0);
+        member.set_position(Random.range(0, world.width), 0);
+      }
+    });
+  }
+}