BEP: Gracefully handle null configurations

Those may occur, e.g., if the target is simply a source file.

Change-Id: Ia64c54e8543dd93712b00428c443922c67e2b6cd
PiperOrigin-RevId: 160278149

5 files changed, 63 insertions, 5 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/TargetCompleteEvent.java b/src/main/java/com/google/devtools/build/lib/analysis/TargetCompleteEvent.java
index 01a3ddf18d..fc1402573a 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/TargetCompleteEvent.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/TargetCompleteEvent.java
@@ -116,8 +116,10 @@ public final class TargetCompleteEvent
 
   @Override
   public BuildEventId getEventId() {
-    return BuildEventId.targetCompleted(
-        getTarget().getLabel(), getTarget().getConfiguration().getEventId());
+    BuildConfiguration config = getTarget().getConfiguration();
+    BuildEventId configId =
+        config == null ? BuildEventId.nullConfigurationId() : config.getEventId();
+    return BuildEventId.targetCompleted(getTarget().getLabel(), configId);
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/TargetConfiguredEvent.java b/src/main/java/com/google/devtools/build/lib/analysis/TargetConfiguredEvent.java
index 8606afe708..2473991981 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/TargetConfiguredEvent.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/TargetConfiguredEvent.java
@@ -47,7 +47,12 @@ public class TargetConfiguredEvent implements BuildEventWithConfiguration {
   public Collection<BuildEventId> getChildrenEvents() {
     ImmutableList.Builder childrenBuilder = ImmutableList.builder();
     for (BuildConfiguration config : configurations) {
-      childrenBuilder.add(BuildEventId.targetCompleted(label, config.getEventId()));
+      if (config != null) {
+        childrenBuilder.add(BuildEventId.targetCompleted(label, config.getEventId()));
+      } else {
+        childrenBuilder.add(
+            BuildEventId.targetCompleted(label, BuildEventId.nullConfigurationId()));
+      }
     }
     return childrenBuilder.build();
   }
diff --git a/src/main/java/com/google/devtools/build/lib/buildeventstream/BuildEventId.java b/src/main/java/com/google/devtools/build/lib/buildeventstream/BuildEventId.java
index c34cdf9fb5..3f4fa37ea5 100644
--- a/src/main/java/com/google/devtools/build/lib/buildeventstream/BuildEventId.java
+++ b/src/main/java/com/google/devtools/build/lib/buildeventstream/BuildEventId.java
@@ -114,6 +114,10 @@ public final class BuildEventId implements Serializable {
         BuildEventStreamProtos.BuildEventId.newBuilder().setConfiguration(configurationId).build());
   }
 
+  public static BuildEventId nullConfigurationId() {
+    return configurationId("none");
+  }
+
   private static BuildEventId targetPatternExpanded(List<String> targetPattern, boolean skipped) {
     BuildEventStreamProtos.BuildEventId.PatternExpandedId patternId =
         BuildEventStreamProtos.BuildEventId.PatternExpandedId.newBuilder()
diff --git a/src/main/java/com/google/devtools/build/lib/buildeventstream/NullConfiguration.java b/src/main/java/com/google/devtools/build/lib/buildeventstream/NullConfiguration.java
new file mode 100644
index 0000000000..a95e5a3d72
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/buildeventstream/NullConfiguration.java
@@ -0,0 +1,42 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// 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.google.devtools.build.lib.buildeventstream;
+
+import com.google.common.collect.ImmutableList;
+import java.util.Collection;
+
+/**
+ * {@link BuildEvent} presenting the configuration in the build event protocol
+ * that internally is just a null pointer.
+ */
+public class NullConfiguration implements BuildEvent {
+
+  @Override
+  public BuildEventId getEventId() {
+    return BuildEventId.nullConfigurationId();
+  }
+
+  @Override
+  public Collection<BuildEventId> getChildrenEvents() {
+    return ImmutableList.of();
+  }
+
+  @Override
+  public BuildEventStreamProtos.BuildEvent asStreamProto(BuildEventConverters converters) {
+    return GenericBuildEvent.protoChaining(this)
+        .setConfiguration(BuildEventStreamProtos.Configuration.getDefaultInstance())
+        .build();
+  }
+}
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 e10444b325..dc14a2b09e 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
@@ -44,6 +44,7 @@ import com.google.devtools.build.lib.buildeventstream.BuildEventStreamProtos.Bui
 import com.google.devtools.build.lib.buildeventstream.BuildEventTransport;
 import com.google.devtools.build.lib.buildeventstream.BuildEventTransportClosedEvent;
 import com.google.devtools.build.lib.buildeventstream.BuildEventWithOrderConstraint;
+import com.google.devtools.build.lib.buildeventstream.NullConfiguration;
 import com.google.devtools.build.lib.buildeventstream.ProgressEvent;
 import com.google.devtools.build.lib.buildtool.BuildRequest;
 import com.google.devtools.build.lib.buildtool.buildevent.BuildCompleteEvent;
@@ -332,14 +333,18 @@ public class BuildEventStreamer implements EventHandler {
   }
 
   private void maybeReportConfiguration(BuildConfiguration configuration) {
-    BuildEventId id = configuration.getEventId();
+    BuildEvent event = configuration;
+    if (configuration == null) {
+      event = new NullConfiguration();
+    }
+    BuildEventId id = event.getEventId();
     synchronized (this) {
       if (configurationsPosted.contains(id)) {
         return;
       }
       configurationsPosted.add(id);
     }
-    post(configuration);
+    post(event);
   }
 
   @Override