From 22e2195a8a15b8151efd6c3ff468692021d53d8a Mon Sep 17 00:00:00 2001
From: paulhu <paulhu@google.com>
Date: Fri, 30 Aug 2019 19:24:36 +0800
Subject: [PATCH] Fix flaky testTcpBufferReset

If EVENT_NETWORK_INFO_CHANGED was handled after waitForIdle()
method done, this test will be failed due to
INetd#setTcpRWmemorySize() was not executed yet. Instead of
waiting for idle state, it's better to use NetworkCallback to
ensure events completely on ConnectivityService.

Bug: 140206578
Test: atest ConnectivityServiceTest#testTcpBufferReset\
      --generate-new-metrics 500

Change-Id: Iad77415db38038603881d9ebe0e37586b549a45c
---
 .../android/server/ConnectivityServiceTest.java   | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java
index a028a54a5b..f6e986eac3 100644
--- a/tests/net/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java
@@ -5692,7 +5692,6 @@ public class ConnectivityServiceTest {
         String[] values = tcpBufferSizes.split(",");
         String rmemValues = String.join(" ", values[0], values[1], values[2]);
         String wmemValues = String.join(" ", values[3], values[4], values[5]);
-        waitForIdle();
         verify(mMockNetd, atLeastOnce()).setTcpRWmemorySize(rmemValues, wmemValues);
         reset(mMockNetd);
     }
@@ -5700,18 +5699,32 @@ public class ConnectivityServiceTest {
     @Test
     public void testTcpBufferReset() throws Exception {
         final String testTcpBufferSizes = "1,2,3,4,5,6";
+        final NetworkRequest networkRequest = new NetworkRequest.Builder()
+                .addTransportType(TRANSPORT_CELLULAR)
+                .addCapability(NET_CAPABILITY_INTERNET)
+                .build();
+        final TestNetworkCallback networkCallback = new TestNetworkCallback();
+        mCm.registerNetworkCallback(networkRequest, networkCallback);
 
         mCellNetworkAgent = new TestNetworkAgentWrapper(TRANSPORT_CELLULAR);
         reset(mMockNetd);
         // Switching default network updates TCP buffer sizes.
         mCellNetworkAgent.connect(false);
+        networkCallback.expectAvailableCallbacksUnvalidated(mCellNetworkAgent);
         verifyTcpBufferSizeChange(ConnectivityService.DEFAULT_TCP_BUFFER_SIZES);
 
         // Change link Properties should have updated tcp buffer size.
         LinkProperties lp = new LinkProperties();
         lp.setTcpBufferSizes(testTcpBufferSizes);
         mCellNetworkAgent.sendLinkProperties(lp);
+        networkCallback.expectCallback(CallbackRecord.LINK_PROPERTIES_CHANGED, mCellNetworkAgent);
         verifyTcpBufferSizeChange(testTcpBufferSizes);
+
+        // Clean up.
+        mCellNetworkAgent.disconnect();
+        networkCallback.expectCallback(CallbackRecord.LOST, mCellNetworkAgent);
+        networkCallback.assertNoCallback();
+        mCm.unregisterNetworkCallback(networkCallback);
     }
 
     @Test