LUCENE-7340: MemoryIndex.toString renamed to toStringDebug; fix NPE

(cherry picked from commit 3ca4fea)

lucene/CHANGES.txt

@@ -25,6 +25,13 @@ New Features
   analyzer for the Ukrainian language (Andriy Rysin via Mike
   McCandless)
 
+Bug Fixes
+
+* LUCENE-6662: Fixed potential resource leaks. (Rishabh Patel via Adrien Grand)
+
+* LUCENE-7340: MemoryIndex.toString() could throw NPE; fixed. Renamed to toStringDebug().
+  (Daniel Collins, David Smiley)
+
 Improvements
 
 * LUCENE-7323: Compound file writing now verifies the incoming

lucene/memory/src/java/org/apache/lucene/index/memory/MemoryIndex.java

@@ -43,10 +43,21 @@ import org.apache.lucene.search.SimpleCollector;
 import org.apache.lucene.search.Sort;
 import org.apache.lucene.search.similarities.Similarity;
 import org.apache.lucene.store.RAMDirectory;
-import org.apache.lucene.util.*;
+import org.apache.lucene.util.ArrayUtil;
+import org.apache.lucene.util.Bits;
+import org.apache.lucene.util.ByteBlockPool;
+import org.apache.lucene.util.BytesRef;
+import org.apache.lucene.util.BytesRefArray;
+import org.apache.lucene.util.BytesRefBuilder;
+import org.apache.lucene.util.BytesRefHash;
 import org.apache.lucene.util.BytesRefHash.DirectBytesStartArray;
+import org.apache.lucene.util.Counter;
+import org.apache.lucene.util.IntBlockPool;
 import org.apache.lucene.util.IntBlockPool.SliceReader;
 import org.apache.lucene.util.IntBlockPool.SliceWriter;
+import org.apache.lucene.util.RecyclingByteBlockAllocator;
+import org.apache.lucene.util.RecyclingIntBlockAllocator;
+import org.apache.lucene.util.StringHelper;
 
 /**
  * High-performance single-document main memory Apache Lucene fulltext search index. 
@@ -746,13 +757,14 @@ public class MemoryIndex {
    * Returns a String representation of the index data for debugging purposes.
    * 
    * @return the string representation
+   * @lucene.experimental
    */
-  @Override
+  public String toStringDebug() {
-  public String toString() {
     StringBuilder result = new StringBuilder(256);
     int sumPositions = 0;
     int sumTerms = 0;
     final BytesRef spare = new BytesRef();
+    final BytesRefBuilder payloadBuilder = storePayloads ? new BytesRefBuilder() : null;
     for (Map.Entry<String, Info> entry : fields.entrySet()) {
       String fieldName = entry.getKey();
       Info info = entry.getValue();
@@ -778,9 +790,16 @@ public class MemoryIndex {
               result.append(", ");
             }
           }
+          if (storePayloads) {
+            int payloadIndex = postingsReader.readInt();
+            if (payloadIndex != -1) {
+                result.append(", " + payloadsBytesRefs.get(payloadBuilder, payloadIndex));
+            }
+          }
           result.append(")");
+
           if (!postingsReader.endOfSlice()) {
-            result.append(",");
+            result.append(", ");
           }
 
         }

lucene/memory/src/test/org/apache/lucene/index/memory/TestMemoryIndex.java

@@ -464,4 +464,26 @@ public class TestMemoryIndex extends LuceneTestCase {
     assertEquals("term", leafReader.getBinaryDocValues("field").get(0).utf8ToString());
   }
 
+  public void testToStringDebug() {
+    MemoryIndex mi = new MemoryIndex(true, true);
+    Analyzer analyzer = new MockPayloadAnalyzer();
+
+    mi.addField("analyzedField", "aa bb aa", analyzer);
+
+    FieldType type = new FieldType();
+    type.setDimensions(1, 4);
+    type.setDocValuesType(DocValuesType.BINARY);
+    type.freeze();
+    mi.addField(new BinaryPoint("pointAndDvField", "term".getBytes(StandardCharsets.UTF_8), type), analyzer);
+
+    assertEquals("analyzedField:\n" +
+        "\t'[61 61]':2: [(0, 0, 2, [70 6f 73 3a 20 30]), (1, 6, 8, [70 6f 73 3a 20 32])]\n" +
+        "\t'[62 62]':1: [(1, 3, 5, [70 6f 73 3a 20 31])]\n" +
+        "\tterms=2, positions=3\n" +
+        "pointAndDvField:\n" +
+        "\tterms=0, positions=0\n" +
+        "\n" +
+        "fields=2, terms=2, positions=3", mi.toStringDebug());
+  }
+
 }