LUCENE-1840: QueryUtils should check that equals() properly handles null

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1001006 13f79535-47bb-0310-9956-ffa450edef68

lucene/src/java/org/apache/lucene/search/function/CustomScoreQuery.java

@@ -145,6 +145,10 @@ public class CustomScoreQuery extends Query {
   /** Returns true if <code>o</code> is equal to this. */
   @Override
   public boolean equals(Object o) {
+    if (this == o)
+      return true;
+    if (!super.equals(o))
+      return false;
     if (getClass() != o.getClass()) {
       return false;
     }

lucene/src/java/org/apache/lucene/search/function/ValueSourceQuery.java

@@ -185,6 +185,10 @@ public class ValueSourceQuery extends Query {
   /** Returns true if <code>o</code> is equal to this. */
   @Override
   public boolean equals(Object o) {
+    if (this == o)
+      return true;
+    if (!super.equals(o))
+      return false;
     if (getClass() != o.getClass()) {
       return false;
     }

lucene/src/test/org/apache/lucene/search/QueryUtils.java

@@ -64,6 +64,9 @@ public class QueryUtils {
     };
     whacky.setBoost(q.getBoost());
     checkUnequal(q, whacky);
+    
+    // null test
+    Assert.assertFalse(q.equals(null));
   }
 
   public static void checkEqual(Query q1, Query q2) {