Implement hashCode, equals for TransitiveTraversalValue and related SkyValues

--
MOS_MIGRATED_REVID=101233095

1 files changed, 12 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/TargetMarkerValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/TargetMarkerValue.java
index eef70843fd..d325de5496 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/TargetMarkerValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/TargetMarkerValue.java
@@ -26,11 +26,23 @@ import com.google.devtools.build.skyframe.SkyValue;
 @ThreadSafe
 public final class TargetMarkerValue implements SkyValue {
 
+  // Note that this value does not guarantee singleton-like reference equality because we use Java
+  // deserialization. java deserialization can create other instances.
   static final TargetMarkerValue TARGET_MARKER_INSTANCE = new TargetMarkerValue();
 
   private TargetMarkerValue() {
   }
 
+  @Override
+  public boolean equals(Object o) {
+    return o instanceof TargetMarkerValue;
+  }
+
+  @Override
+  public int hashCode() {
+    return 42;
+  }
+
   @ThreadSafe
   public static SkyKey key(Label label) {
     return new SkyKey(SkyFunctions.TARGET_MARKER, label);