Add framework for reliably reproducing race conditions.

Bug: 120628042
Test: RaceConditionReproducerTest
Change-Id: Id658e2b0da6af186b76501ff16edbd135dda3c9b

1 files changed, 38 insertions, 0 deletions

diff --git a/src/com/android/launcher3/util/RaceConditionTracker.java b/src/com/android/launcher3/util/RaceConditionTracker.java
new file mode 100644
index 000000000..8eafb551d
--- /dev/null
+++ b/src/com/android/launcher3/util/RaceConditionTracker.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.launcher3.util;
+
+/**
+ * Event tracker for reliably reproducing race conditions in tests.
+ * The app should call onEvent() for events that the test will try to reproduce in all possible
+ * orders.
+ */
+public class RaceConditionTracker {
+    public interface EventProcessor {
+        void onEvent(String eventName);
+    }
+
+    private static EventProcessor sEventProcessor;
+
+    static void setEventProcessor(EventProcessor eventProcessor) {
+        sEventProcessor = eventProcessor;
+    }
+
+    public static void onEvent(String eventName) {
+        if (sEventProcessor != null) sEventProcessor.onEvent(eventName);
+    }
+}