2 files changed, 28 insertions, 6 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java b/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java
index c0c50958b5..a79297d396 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BuildEventStreamer.java
@@ -43,8 +43,8 @@ import java.util.logging.Logger;
 public class BuildEventStreamer implements EventHandler {
   private final Collection<BuildEventTransport> transports;
   private Set<BuildEventId> announcedEvents;
-  private Set<BuildEventId> postedEvents;
-  private final Multimap<BuildEventId, BuildEvent> pendingEvents;
+  private final Set<BuildEventId> postedEvents = new HashSet<>();
+  private final Multimap<BuildEventId, BuildEvent> pendingEvents = HashMultimap.create();
   private int progressCount;
   private AbortReason abortReason = AbortReason.UNKNOWN;
   private static final Logger log = Logger.getLogger(BuildEventStreamer.class.getName());
@@ -52,9 +52,7 @@ public class BuildEventStreamer implements EventHandler {
   public BuildEventStreamer(Collection<BuildEventTransport> transports) {
     this.transports = transports;
     this.announcedEvents = null;
-    this.postedEvents = null;
     this.progressCount = 0;
-    this.pendingEvents = HashMultimap.create();
   }
 
   /**
@@ -71,7 +69,6 @@ public class BuildEventStreamer implements EventHandler {
     synchronized (this) {
       if (announcedEvents == null) {
         announcedEvents = new HashSet<>();
-        postedEvents = new HashSet<>();
         if (!event.getChildrenEvents().contains(ProgressEvent.INITIAL_PROGRESS_UPDATE)) {
           linkEvent = ProgressEvent.progressChainIn(progressCount, event.getEventId());
           progressCount++;
@@ -85,8 +82,8 @@ public class BuildEventStreamer implements EventHandler {
           announcedEvents.addAll(linkEvent.getChildrenEvents());
           postedEvents.add(linkEvent.getEventId());
         }
-        postedEvents.add(id);
       }
+      postedEvents.add(id);
       announcedEvents.addAll(event.getChildrenEvents());
     }
 
diff --git a/src/test/java/com/google/devtools/build/lib/runtime/BuildEventStreamerTest.java b/src/test/java/com/google/devtools/build/lib/runtime/BuildEventStreamerTest.java
index 433f9fb4d8..5a4e444bfe 100644
--- a/src/test/java/com/google/devtools/build/lib/runtime/BuildEventStreamerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/runtime/BuildEventStreamerTest.java
@@ -297,4 +297,29 @@ public class BuildEventStreamerTest {
     assertEquals(rootCauseId, allEventsSeen.get(3).getEventId());
     assertEquals(failedTarget.getEventId(), allEventsSeen.get(4).getEventId());
   }
+
+  @Test
+  public void testVeryFirstEventNeedsToWait() {
+    // Verify that we can handle an first event waiting for another event.
+    RecordingBuildEventTransport transport = new RecordingBuildEventTransport();
+    BuildEventStreamer streamer =
+        new BuildEventStreamer(ImmutableSet.<BuildEventTransport>of(transport));
+
+    BuildEventId initialId = testId("Initial");
+    BuildEventId waitId = testId("Waiting for initial event");
+    BuildEvent startEvent =
+        new GenericBuildEvent(
+            initialId,
+            ImmutableSet.<BuildEventId>of(ProgressEvent.INITIAL_PROGRESS_UPDATE, waitId));
+    BuildEvent waitingForStart =
+        new GenericOrderEvent(waitId, ImmutableSet.<BuildEventId>of(), ImmutableSet.of(initialId));
+
+    streamer.buildEvent(waitingForStart);
+    streamer.buildEvent(startEvent);
+
+    List<BuildEvent> allEventsSeen = transport.getEvents();
+    assertThat(allEventsSeen).hasSize(2);
+    assertEquals(startEvent.getEventId(), allEventsSeen.get(0).getEventId());
+    assertEquals(waitingForStart.getEventId(), allEventsSeen.get(1).getEventId());
+  }
 }