Clean up a few Skylark-Skyframe structures

Add value-class methods to SkylarkFileDependency and SkylarkImportLookupValue. Remove Java serialization hack from Extension.

RELNOTES: None
PiperOrigin-RevId: 162383283

1 files changed, 29 insertions, 8 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkFileDependency.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkFileDependency.java
index 36a7516e2f..0167aea98e 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkFileDependency.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkylarkFileDependency.java
@@ -16,19 +16,20 @@ package com.google.devtools.build.lib.skyframe;
 
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.cmdline.Label;
-
-import java.io.Serializable;
+import java.util.Objects;
 
 /**
- * A simple value class to store the direct Skylark file dependencies of a Skylark
- * extension file. It also contains a Label identifying the extension file.
+ * A simple value class to store the direct Skylark file dependencies of a Skylark extension file.
+ * It also contains a Label identifying the extension file.
+ *
+ * <p>The dependency structure must be acyclic.
  */
-class SkylarkFileDependency implements Serializable {
+public class SkylarkFileDependency {
 
   private final Label label;
   private final ImmutableList<SkylarkFileDependency> dependencies;
 
-  SkylarkFileDependency(Label label, ImmutableList<SkylarkFileDependency> dependencies) {
+  public SkylarkFileDependency(Label label, ImmutableList<SkylarkFileDependency> dependencies) {
     this.label = label;
     this.dependencies = dependencies;
   }
@@ -37,14 +38,34 @@ class SkylarkFileDependency implements Serializable {
    * Returns the list of direct Skylark file dependencies of the Skylark extension file
    * corresponding to this object.
    */
-  ImmutableList<SkylarkFileDependency> getDependencies() {
+  public ImmutableList<SkylarkFileDependency> getDependencies() {
     return dependencies;
   }
 
   /**
    * Returns the Label of the Skylark extension file corresponding to this object.
    */
-  Label getLabel() {
+  public Label getLabel() {
     return label;
   }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (this == obj) {
+      return true;
+    }
+    if (!(obj instanceof SkylarkFileDependency)) {
+      return false;
+    }
+    SkylarkFileDependency other = (SkylarkFileDependency) obj;
+    if (!label.equals(other.getLabel())) {
+      return false;
+    }
+    return dependencies.equals(other.getDependencies());
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(label, dependencies);
+  }
 }