lucene/SOLR-12096.patch

diff --git a/solr/core/src/java/org/apache/solr/response/GeoJSONResponseWriter.java b/solr/core/src/java/org/apache/solr/response/GeoJSONResponseWriter.java
index 43fd7b4..012290e 100644
--- a/solr/core/src/java/org/apache/solr/response/GeoJSONResponseWriter.java
+++ b/solr/core/src/java/org/apache/solr/response/GeoJSONResponseWriter.java
@@ -166,7 +166,8 @@ class GeoJSONWriter extends JSONWriter {
 
       // SolrDocument will now have multiValued fields represented as a Collection,
       // even if only a single value is returned for this document.
-      if (val instanceof List) {
+      // For SolrDocumentList, use writeVal instead of writeArray
+      if (!(val instanceof SolrDocumentList) && val instanceof List) {
         // shortcut this common case instead of going through writeVal again
         writeArray(name,((Iterable)val).iterator());
       } else {
diff --git a/solr/core/src/java/org/apache/solr/response/JSONResponseWriter.java b/solr/core/src/java/org/apache/solr/response/JSONResponseWriter.java
index 513df4e..5f6e2f2 100644
--- a/solr/core/src/java/org/apache/solr/response/JSONResponseWriter.java
+++ b/solr/core/src/java/org/apache/solr/response/JSONResponseWriter.java
@@ -25,10 +25,11 @@ import java.util.Map;
 import java.util.Set;
 
 import org.apache.solr.common.IteratorWriter;
+import org.apache.solr.common.MapWriter;
 import org.apache.solr.common.MapWriter.EntryWriter;
 import org.apache.solr.common.PushWriter;
 import org.apache.solr.common.SolrDocument;
-import org.apache.solr.common.MapWriter;
+import org.apache.solr.common.SolrDocumentList;
 import org.apache.solr.common.params.SolrParams;
 import org.apache.solr.common.util.NamedList;
 import org.apache.solr.common.util.SimpleOrderedMap;
@@ -367,7 +368,8 @@ class JSONWriter extends TextResponseWriter {
 
       // SolrDocument will now have multiValued fields represented as a Collection,
       // even if only a single value is returned for this document.
-      if (val instanceof List) {
+      // For SolrDocumentList, use writeVal instead of writeArray
+      if (!(val instanceof SolrDocumentList) && val instanceof List) {
         // shortcut this common case instead of going through writeVal again
         writeArray(name,((Iterable)val).iterator());
       } else {
diff --git a/solr/core/src/test/org/apache/solr/response/JSONWriterTest.java b/solr/core/src/test/org/apache/solr/response/JSONWriterTest.java
index 1b53150..68cebd2 100644
--- a/solr/core/src/test/org/apache/solr/response/JSONWriterTest.java
+++ b/solr/core/src/test/org/apache/solr/response/JSONWriterTest.java
@@ -22,7 +22,10 @@ import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
+
+import org.apache.solr.JSONTestUtil;
 import org.apache.solr.SolrTestCaseJ4;
 import org.apache.solr.common.SolrDocument;
 import org.apache.solr.common.SolrDocumentList;
@@ -130,9 +133,9 @@ public class JSONWriterTest extends SolrTestCaseJ4 {
   }
 
   @Test
-  public void testJSONSolrDocument() throws IOException {
+  public void testJSONSolrDocument() throws Exception {
     SolrQueryRequest req = req(CommonParams.WT,"json",
-                               CommonParams.FL,"id,score");
+                               CommonParams.FL,"id,score,_children_,path");
     SolrQueryResponse rsp = new SolrQueryResponse();
     JSONResponseWriter w = new JSONResponseWriter();
 
@@ -141,11 +144,22 @@ public class JSONWriterTest extends SolrTestCaseJ4 {
 
     StringWriter buf = new StringWriter();
 
+    SolrDocument childDoc = new SolrDocument();
+    childDoc.addField("id", "2");
+    childDoc.addField("score", "0.4");
+    childDoc.addField("path", Arrays.asList("a>b", "a>b>c"));
+
+    SolrDocumentList childList = new SolrDocumentList();
+    childList.setNumFound(1);
+    childList.setStart(0);
+    childList.add(childDoc);
+
     SolrDocument solrDoc = new SolrDocument();
     solrDoc.addField("id", "1");
     solrDoc.addField("subject", "hello2");
     solrDoc.addField("title", "hello3");
     solrDoc.addField("score", "0.7");
+    solrDoc.setField("_children_", childList);
 
     SolrDocumentList list = new SolrDocumentList();
     list.setNumFound(1);
@@ -163,8 +177,12 @@ public class JSONWriterTest extends SolrTestCaseJ4 {
                 result.contains("\"title\""));
     assertTrue("response doesn't contain expected fields: " + result, 
                result.contains("\"id\"") &&
-               result.contains("\"score\""));
+               result.contains("\"score\"") && result.contains("_children_"));
 
+    String expectedResult = "{'response':{'numFound':1,'start':0,'maxScore':0.7,'docs':[{'id':'1', 'score':'0.7'," +
+        " '_children_':{'numFound':1,'start':0,'docs':[{'id':'2', 'score':'0.4', 'path':['a>b', 'a>b>c']}] }}] }}";
+    String error = JSONTestUtil.match(result, "=="+expectedResult);
+    assertNull("response validation failed with error: " + error, error);
 
     req.close();
   }
diff --git a/solr/core/src/test/org/apache/solr/response/transform/TestSubQueryTransformerDistrib.java b/solr/core/src/test/org/apache/solr/response/transform/TestSubQueryTransformerDistrib.java
index 620cac0..f6d0a38 100644
--- a/solr/core/src/test/org/apache/solr/response/transform/TestSubQueryTransformerDistrib.java
+++ b/solr/core/src/test/org/apache/solr/response/transform/TestSubQueryTransformerDistrib.java
@@ -16,7 +16,11 @@
  */
 package org.apache.solr.response.transform;
 
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.nio.charset.Charset;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.ArrayList;
@@ -26,6 +30,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.Random;
 
+import org.apache.commons.io.IOUtils;
+import org.apache.solr.JSONTestUtil;
 import org.apache.solr.client.solrj.SolrServerException;
 import org.apache.solr.client.solrj.impl.CloudSolrClient;
 import org.apache.solr.client.solrj.request.CollectionAdminRequest;
@@ -37,10 +43,12 @@ import org.apache.solr.cloud.SolrCloudTestCase;
 import org.apache.solr.common.SolrDocument;
 import org.apache.solr.common.SolrDocumentList;
 import org.apache.solr.common.cloud.ZkStateReader;
+import org.apache.solr.common.params.ModifiableSolrParams;
 import org.apache.solr.common.util.ContentStreamBase;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
+@org.apache.solr.SolrTestCaseJ4.SuppressSSL()
 public class TestSubQueryTransformerDistrib extends SolrCloudTestCase {
   
   private static final String support = "These guys help customers";
@@ -92,7 +100,7 @@ public class TestSubQueryTransformerDistrib extends SolrCloudTestCase {
   
   @SuppressWarnings("serial")
   @Test
-  public void test() throws SolrServerException, IOException {
+  public void test() throws Exception {
     int peopleMultiplier = atLeast(1);
     int deptMultiplier = atLeast(1);
     
@@ -100,24 +108,26 @@ public class TestSubQueryTransformerDistrib extends SolrCloudTestCase {
     
     Random random1 = random();
     
+    final ModifiableSolrParams params = params(
+        new String[]{"q","name_s:dave", "indent","true",
+            "fl","*,depts:[subquery "+((random1.nextBoolean() ? "" : "separator=,"))+"]",
+            "rows","" + peopleMultiplier,
+            "depts.q","{!terms f=dept_id_s v=$row.dept_ss_dv "+((random1.nextBoolean() ? "" : "separator=,"))+"}",
+            "depts.fl","text_t"+(differentUniqueId?",id:notid":""),
+            "depts.indent","true",
+            "depts.collection","departments",
+            differentUniqueId ? "depts.distrib.singlePass":"notnecessary","true",
+            "depts.rows",""+(deptMultiplier*2),
+            "depts.logParamsList","q,fl,rows,row.dept_ss_dv",
+            random().nextBoolean()?"depts.wt":"whatever",anyWt(),
+            random().nextBoolean()?"wt":"whatever",anyWt()});
+
+    final SolrDocumentList hits;
     {
-     
-      final QueryRequest  qr = new QueryRequest(params(
-          new String[]{"q","name_s:dave", "indent","true",
-          "fl","*,depts:[subquery "+((random1.nextBoolean() ? "" : "separator=,"))+"]", 
-          "rows","" + peopleMultiplier,
-          "depts.q","{!terms f=dept_id_s v=$row.dept_ss_dv "+((random1.nextBoolean() ? "" : "separator=,"))+"}", 
-          "depts.fl","text_t"+(differentUniqueId?",id:notid":""),
-          "depts.indent","true",
-          "depts.collection","departments",
-          differentUniqueId ? "depts.distrib.singlePass":"notnecessary","true",
-          "depts.rows",""+(deptMultiplier*2),
-          "depts.logParamsList","q,fl,rows,row.dept_ss_dv",
-          random().nextBoolean()?"depts.wt":"whatever",anyWt(),
-          random().nextBoolean()?"wt":"whatever",anyWt()}));
+      final QueryRequest qr = new QueryRequest(params);
       final QueryResponse  rsp = new QueryResponse();
-      rsp.setResponse(cluster.getSolrClient().request(qr, people));
-      final SolrDocumentList hits = rsp.getResults();
+      rsp.setResponse(cluster.getSolrClient().request(qr, people+","+depts));
+      hits = rsp.getResults();
       
       assertEquals(peopleMultiplier, hits.getNumFound());
       
@@ -140,6 +150,21 @@ public class TestSubQueryTransformerDistrib extends SolrCloudTestCase {
       }
       assertEquals(hits.toString(), engineerCount, supportCount); 
     }
+
+    params.set("wt", "json");
+    final URL node = new URL(cluster.getRandomJetty(random()).getBaseUrl().toString()
+     +"/"+people+"/select"+params.toQueryString());
+
+    try(final InputStream jsonResponse = node.openStream()){
+      final ByteArrayOutputStream outBuffer = new ByteArrayOutputStream();
+      IOUtils.copy(jsonResponse, outBuffer);
+
+      final Object expected = ((SolrDocumentList) hits.get(0).getFieldValue("depts")).get(0).get("text_t");
+      final String err = JSONTestUtil.match("/response/docs/[0]/depts/docs/[0]/text_t"
+          ,outBuffer.toString(Charset.forName("UTF-8").toString()),
+          "\""+expected+"\"");
+      assertNull(err,err);
+    }
     
   }