[TEST] use ParseField instead of plain strings in query tests

core/src/main/java/org/elasticsearch/index/query/MoreLikeThisQueryBuilder.java

@@ -147,7 +147,7 @@ public class MoreLikeThisQueryBuilder extends AbstractQueryBuilder<MoreLikeThisQ
      */
     public static final class Item implements ToXContent, Writeable {
         public static final Item[] EMPTY_ARRAY = new Item[0];
-
+        
         public interface Field {
             ParseField INDEX = new ParseField("_index");
             ParseField TYPE = new ParseField("_type");

core/src/test/java/org/elasticsearch/index/query/MoreLikeThisQueryBuilderTests.java

@@ -202,7 +202,7 @@ public class MoreLikeThisQueryBuilderTests extends AbstractQueryTestCase<MoreLik
     @Override
     protected Set<String> getObjectsHoldingArbitraryContent() {
         //doc contains arbitrary content, anything can be added to it and no exception will be thrown
-        return Collections.singleton("doc");
+        return Collections.singleton(MoreLikeThisQueryBuilder.Item.Field.DOC.getPreferredName());
     }
 
     @Override

core/src/test/java/org/elasticsearch/index/query/ScriptQueryBuilderTests.java

@@ -87,6 +87,6 @@ public class ScriptQueryBuilderTests extends AbstractQueryTestCase<ScriptQueryBu
     protected Set<String> getObjectsHoldingArbitraryContent() {
         //script_score.script.params can contain arbitrary parameters. no error is expected when
         //adding additional objects within the params object.
-        return Collections.singleton("params");
+        return Collections.singleton(Script.ScriptField.PARAMS.getPreferredName());
     }
 }

core/src/test/java/org/elasticsearch/index/query/functionscore/FunctionScoreQueryBuilderTests.java

@@ -108,7 +108,8 @@ public class FunctionScoreQueryBuilderTests extends AbstractQueryTestCase<Functi
     protected Set<String> getObjectsHoldingArbitraryContent() {
         //script_score.script.params can contain arbitrary parameters. no error is expected when adding additional objects
         //within the params object. Score functions get parsed in the data nodes, so they are not validated in the coord node.
-        return new HashSet<>(Arrays.asList("params", "exp", "linear", "gauss"));
+        return new HashSet<>(Arrays.asList(Script.ScriptField.PARAMS.getPreferredName(), ExponentialDecayFunctionBuilder.NAME,
+                LinearDecayFunctionBuilder.NAME, GaussDecayFunctionBuilder.NAME));
     }
 
     /**

modules/percolator/src/test/java/org/elasticsearch/percolator/PercolateQueryBuilderTests.java

@@ -171,7 +171,7 @@ public class PercolateQueryBuilderTests extends AbstractQueryTestCase<PercolateQ
     @Override
     protected Set<String> getObjectsHoldingArbitraryContent() {
         //document contains arbitrary content, no error expected when an object is added to it
-        return Collections.singleton("document");
+        return Collections.singleton(PercolateQueryBuilder.DOCUMENT_FIELD.getPreferredName());
     }
 
     public void testRequiredParameters() {