Throw parsing error if common terms query contains multiple fields in its short version

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

@@ -345,6 +345,10 @@ public class CommonTermsQueryBuilder extends AbstractQueryBuilder<CommonTermsQue
                     }
                 }
             } else {
+                if (fieldName != null) {
+                    throw new ParsingException(parser.getTokenLocation(), "[common] query doesn't support multiple fields, found ["
+                            + fieldName + "] and [" + parser.currentName() + "]");
+                }
                 fieldName = parser.currentName();
                 text = parser.objectText();
             }

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

@@ -194,5 +194,14 @@ public class CommonTermsQueryBuilderTests extends AbstractQueryTestCase<CommonTe
 
         ParsingException e = expectThrows(ParsingException.class, () -> parseQuery(json));
         assertEquals("[common] query doesn't support multiple fields, found [message1] and [message2]", e.getMessage());
+
+        String shortJson = "{\n" +
+                "  \"common\" : {\n" +
+                "    \"message1\" : \"nelly the elephant not as a cartoon\",\n" +
+                "    \"message2\" : \"nelly the elephant not as a cartoon\"\n" +
+                "  }\n" +
+                "}";
+        e = expectThrows(ParsingException.class, () -> parseQuery(shortJson));
+        assertEquals("[common] query doesn't support multiple fields, found [message1] and [message2]", e.getMessage());
     }
 }