Refactor getParentWithSkylarkModule() into SkylarkInterfaceUtils

--
MOS_MIGRATED_REVID=135956016

1 files changed, 32 insertions, 13 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skylarkinterface/SkylarkInterfaceUtils.java b/src/main/java/com/google/devtools/build/lib/skylarkinterface/SkylarkInterfaceUtils.java
index 348a9ccef4..bee73efaf8 100644
--- a/src/main/java/com/google/devtools/build/lib/skylarkinterface/SkylarkInterfaceUtils.java
+++ b/src/main/java/com/google/devtools/build/lib/skylarkinterface/SkylarkInterfaceUtils.java
@@ -14,6 +14,7 @@
 
 package com.google.devtools.build.lib.skylarkinterface;
 
+import com.google.devtools.build.lib.util.Pair;
 import java.lang.reflect.Method;
 import javax.annotation.Nullable;
 
@@ -22,33 +23,51 @@ import javax.annotation.Nullable;
  */
 public class SkylarkInterfaceUtils {
 
-  /**
-   * Returns the {@link SkylarkModule} annotation for the given class, if it exists, and
-   * null otherwise. The first annotation found will be returned, starting with {@code classObj}
-   * and following its base classes and interfaces recursively.
-   */
   @Nullable
-  public static SkylarkModule getSkylarkModule(Class<?> classObj) {
+  private static Pair<Class<?>, SkylarkModule> searchForSkylarkModule(Class<?> classObj) {
     if (classObj.isAnnotationPresent(SkylarkModule.class)) {
-      return classObj.getAnnotation(SkylarkModule.class);
+      return new Pair<Class<?>, SkylarkModule>(
+          classObj, classObj.getAnnotation(SkylarkModule.class));
     }
     Class<?> superclass = classObj.getSuperclass();
     if (superclass != null) {
-      SkylarkModule annotation = getSkylarkModule(superclass);
-      if (annotation != null) {
-        return annotation;
+      Pair<Class<?>, SkylarkModule> result = searchForSkylarkModule(superclass);
+      if (result != null) {
+        return result;
       }
     }
     for (Class<?> interfaceObj : classObj.getInterfaces()) {
-      SkylarkModule annotation = getSkylarkModule(interfaceObj);
-      if (annotation != null) {
-        return annotation;
+      Pair<Class<?>, SkylarkModule> result = searchForSkylarkModule(interfaceObj);
+      if (result != null) {
+        return result;
       }
     }
     return null;
   }
 
   /**
+   * Returns the {@link SkylarkModule} annotation for the given class, if it exists, and
+   * null otherwise. The first annotation found will be returned, starting with {@code classObj}
+   * and following its base classes and interfaces recursively.
+   */
+  @Nullable
+  public static SkylarkModule getSkylarkModule(Class<?> classObj) {
+    Pair<Class<?>, SkylarkModule> result = searchForSkylarkModule(classObj);
+    return result == null ? null : result.second;
+  }
+
+  /**
+   * Searches {@code classObj}'s class hierarchy and returns the first superclass or interface that
+   * is annotated with {@link SkylarkModule} (including possibly {@code classObj} itself), or null
+   * if none is found.
+   */
+  @Nullable
+  public static Class<?> getParentWithSkylarkModule(Class<?> classObj) {
+    Pair<Class<?>, SkylarkModule> result = searchForSkylarkModule(classObj);
+    return result == null ? null : result.first;
+  }
+
+  /**
    * Returns the {@link SkylarkCallable} annotation for the given method, if it exists, and
    * null otherwise. The first annotation of an overridden version of the method that is found
    * will be returned, starting with {@code classObj} and following its base classes and