fixed flaky mocking in AbstractSocketAppenderTest due to multi-thread…

…ing issues

logback-core/src/test/java/ch/qos/logback/core/net/AbstractSocketAppenderTest.java

@@ -76,7 +76,7 @@ public class AbstractSocketAppenderTest {
 
   @Before
   public void setupValidAppenderWithMockDependencies() throws Exception {
-    doReturn(socket).when(socketConnector).call();
+
     doReturn(objectWriter).when(objectWriterFactory).newAutoFlushingObjectWriter(any(OutputStream.class));
     doReturn(deque).when(queueFactory).<String>newLinkedBlockingDeque(anyInt());
 
@@ -89,8 +89,6 @@ public void tearDown() throws Exception {
     appender.stop();
     assertFalse(appender.isStarted());
 
-    breakOutSocketReConnectionLoop();
-
     executorService.shutdownNow();
     assertTrue(executorService.awaitTermination(TIMEOUT, TimeUnit.MILLISECONDS));
   }
@@ -191,9 +189,10 @@ public void createsSocketConnectorWithConfiguredParameters() throws Exception {
   }
 
   @Test
-  public void addsInfoMessageWhenSocketConnectionWasEstablished() {
+  public void addsInfoMessageWhenSocketConnectionWasEstablished() throws Exception {
 
     // when
+    mockOneSuccessfulSocketConnection();
     appender.start();
 
     // then
@@ -204,6 +203,7 @@ public void addsInfoMessageWhenSocketConnectionWasEstablished() {
   public void addsInfoMessageWhenSocketConnectionFailed() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     doThrow(new IOException()).when(objectWriterFactory).newAutoFlushingObjectWriter(any(OutputStream.class));
     appender.start();
 
@@ -218,6 +218,7 @@ public void addsInfoMessageWhenSocketConnectionFailed() throws Exception {
   public void closesSocketOnException() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     doThrow(new IOException()).when(objectWriterFactory).newAutoFlushingObjectWriter(any(OutputStream.class));
     appender.start();
 
@@ -232,6 +233,7 @@ public void closesSocketOnException() throws Exception {
   public void addsInfoMessageWhenSocketConnectionClosed() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     doThrow(new IOException()).when(objectWriterFactory).newAutoFlushingObjectWriter(any(OutputStream.class));
     appender.start();
 
@@ -246,6 +248,7 @@ public void addsInfoMessageWhenSocketConnectionClosed() throws Exception {
   public void shutsDownOnInterruptWhileWaitingForEvent() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     doThrow(new InterruptedException()).when(deque).takeFirst();
 
     // when
@@ -328,6 +331,7 @@ public void addsInfoMessageWhenEventCouldNotBeQueuedInConfiguredTimeoutDueToQueu
   public void takesEventsFromTheFrontOfTheDeque() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     appender.start();
     awaitStartOfEventDispatching();
 
@@ -342,6 +346,7 @@ public void takesEventsFromTheFrontOfTheDeque() throws Exception {
   public void reAddsEventAtTheFrontOfTheDequeWhenTransmissionFails() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     doThrow(new IOException()).when(objectWriter).write(anyObject());
     appender.start();
     awaitStartOfEventDispatching();
@@ -372,6 +377,7 @@ public void addsErrorMessageWhenAppendingIsInterruptedWhileWaitingForTheQueueToA
   public void postProcessesEventsBeforeTransformingItToASerializable() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     appender.start();
     awaitStartOfEventDispatching();
 
@@ -389,6 +395,7 @@ public void postProcessesEventsBeforeTransformingItToASerializable() throws Exce
   public void writesSerializedEventToStream() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     when(preSerializationTransformer.transform("some event")).thenReturn("some serialized event");
     appender.start();
     awaitStartOfEventDispatching();
@@ -404,6 +411,7 @@ public void writesSerializedEventToStream() throws Exception {
   public void addsInfoMessageWhenEventIsBeingDroppedBecauseOfConnectionProblemAndDequeCapacityLimitReached() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     doThrow(new IOException()).when(objectWriter).write(anyObject());
     doReturn(false).when(deque).offerFirst("some event");
     appender.start();
@@ -421,6 +429,7 @@ public void addsInfoMessageWhenEventIsBeingDroppedBecauseOfConnectionProblemAndD
   public void reEstablishesSocketConnectionOnConnectionDropWhenWritingEvent() throws Exception {
 
     // given
+    mockTwoSuccessfulSocketConnections();
     doThrow(new IOException()).when(objectWriter).write(anyObject());
     appender.start();
     awaitStartOfEventDispatching();
@@ -436,6 +445,7 @@ public void reEstablishesSocketConnectionOnConnectionDropWhenWritingEvent() thro
   public void triesToReEstablishSocketConnectionIfItFailed() throws Exception {
 
     // given
+    mockOneSuccessfulSocketConnection();
     doThrow(new IOException()).when(socket).getOutputStream();
     appender.start();
 
@@ -450,6 +460,7 @@ public void triesToReEstablishSocketConnectionIfItFailed() throws Exception {
   public void usesConfiguredAcceptConnectionTimeoutAndResetsSocketTimeoutAfterSuccessfulConnection() throws Exception {
 
     // when
+    mockOneSuccessfulSocketConnection();
     appender.setAcceptConnectionTimeout(42);
     appender.start();
     awaitStartOfEventDispatching();
@@ -468,8 +479,12 @@ private void awaitStartOfEventDispatching() throws InterruptedException {
     verify(deque, timeout(TIMEOUT)).takeFirst();
   }
 
-  private void breakOutSocketReConnectionLoop() throws InterruptedException {
-    doReturn(null).when(socketConnector).call();
+  private void mockOneSuccessfulSocketConnection() throws InterruptedException {
+    doReturn(socket).doReturn(null).when(socketConnector).call();
+  }
+
+  private void mockTwoSuccessfulSocketConnections() throws InterruptedException {
+    doReturn(socket).doReturn(socket).doReturn(null).when(socketConnector).call();
   }
 
   private static class InstrumentedSocketAppender extends AbstractSocketAppender<String> {