#1834 Reset tap state after successful tap

packages/flutter/lib/src/gestures/tap.dart

@@ -58,10 +58,9 @@ class TapGestureRecognizer extends PrimaryPointerGestureRecognizer {
     super.rejectGesture(pointer);
     if (pointer == primaryPointer) {
       assert(state == GestureRecognizerState.defunct);
-      _wonArena = false;
-      _finalPosition = null;
       if (onTapCancel != null)
         onTapCancel();
+      _reset();
     }
   }
 
@@ -72,8 +71,14 @@ class TapGestureRecognizer extends PrimaryPointerGestureRecognizer {
         onTapUp(_finalPosition);
       if (onTap != null)
         onTap();
+      _reset();
     }
   }
+
+  void _reset() {
+    _wonArena = false;
+    _finalPosition = null;
+  }
 }
 
 /// TapTracker helps track individual tap sequences as part of a

packages/unit/test/gestures/tap_test.dart

@@ -84,6 +84,40 @@ void main() {
     tap.dispose();
   });
 
+  test('No duplicate tap events', () {
+    PointerRouter router = new PointerRouter();
+    TapGestureRecognizer tap = new TapGestureRecognizer(router: router);
+
+    int tapsRecognized = 0;
+    tap.onTap = () {
+      tapsRecognized++;
+    };
+
+    tap.addPointer(down1);
+    GestureArena.instance.close(1);
+    expect(tapsRecognized, 0);
+    router.route(down1);
+    expect(tapsRecognized, 0);
+
+    router.route(up1);
+    expect(tapsRecognized, 1);
+    GestureArena.instance.sweep(1);
+    expect(tapsRecognized, 1);
+
+    tap.addPointer(down1);
+    GestureArena.instance.close(1);
+    expect(tapsRecognized, 1);
+    router.route(down1);
+    expect(tapsRecognized, 1);
+
+    router.route(up1);
+    expect(tapsRecognized, 2);
+    GestureArena.instance.sweep(1);
+    expect(tapsRecognized, 2);
+
+    tap.dispose();
+  });
+
   test('Should not recognize two overlapping taps', () {
     PointerRouter router = new PointerRouter();
     TapGestureRecognizer tap = new TapGestureRecognizer(router: router);