Handle short form queries

src/Nest/CommonAbstractions/SerializationBehavior/GenericJsonConverters/FromJson.cs

@@ -10,7 +10,7 @@ internal static class FromJson
 		/// </summary>
 		public static T ReadAs<T>(JsonReader reader, JsonSerializer serializer)
 		{
-			var t = (T)typeof(T).CreateInstance();
+			var t = typeof(T).CreateInstance<T>();
 			serializer.Populate(reader, t);
 			return t;
 		}

src/Nest/QueryDsl/Abstractions/FieldName/FieldNameQueryJsonConverter.cs

@@ -8,14 +8,39 @@ internal class FieldNameQueryJsonConverter<TReadAs> : ReserializeJsonConverter<T
 	{
 		protected override object DeserializeJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
 		{
-			//{
 			reader.Read(); //property name
-			var fieldName = reader.Value as string;
-			reader.Read(); //{
-			var query = ReadAs(reader, objectType, existingValue, serializer);
+			var fieldName = (string)reader.Value;
+			reader.Read();
+			TReadAs query = null;
 
-			if (query == null) return null;
+			switch (reader.TokenType)
+			{
+				case JsonToken.StartObject:
+					query = ReadAs(reader, objectType, existingValue, serializer);
+					break;
+				case JsonToken.Null:
+					break;
+				default:
+					query = new TReadAs();
+					switch (query)
+					{
+						case ITermQuery termQuery:
+							termQuery.Value = reader.Value;
+							break;
+						case IMatchQuery matchQuery:
+							matchQuery.Query = (string)reader.Value;
+							break;
+						case IMatchPhraseQuery matchPhraseQuery:
+							matchPhraseQuery.Query = (string)reader.Value;
+							break;
+						case IMatchPhrasePrefixQuery matchPhrasePrefixQuery:
+							matchPhrasePrefixQuery.Query = (string)reader.Value;
+							break;
+					}
+					break;
+			}
 
+			if (query == null) return null;
 			query.Field = fieldName;
 
 			return query;

src/Tests/Tests/QueryDsl/FullText/Match/MatchUsageTests.cs

@@ -1,4 +1,7 @@
-using Nest;
+using System.IO;
+using Elastic.Xunit.XunitPlumbing;
+using FluentAssertions;
+using Nest;
 using Tests.Core.ManagedElasticsearch.Clusters;
 using Tests.Domain;
 using Tests.Framework.Integration;
@@ -69,5 +72,15 @@ protected override QueryContainer QueryFluent(QueryContainerDescriptor<Project>
 				.FuzzyRewrite(MultiTermQueryRewrite.TopTermsBlendedFreqs(10))
 				.Name("named_query")
 			);
+
+		//hide
+		[U] public void DeserializeShortForm()
+		{
+			using var stream = new MemoryStream(ShortFormQuery);
+			var query = Client.RequestResponseSerializer.Deserialize<IMatchQuery>(stream);
+			query.Should().NotBeNull();
+			query.Field.Should().Be(new Field("description"));
+			query.Query.Should().Be("project description");
+		}
 	}
 }

src/Tests/Tests/QueryDsl/FullText/MatchPhrase/MatchPhraseUsageTests.cs

@@ -1,4 +1,7 @@
-using Nest;
+using System.IO;
+using Elastic.Xunit.XunitPlumbing;
+using FluentAssertions;
+using Nest;
 using Tests.Core.ManagedElasticsearch.Clusters;
 using Tests.Domain;
 using Tests.Framework.Integration;
@@ -51,5 +54,15 @@ protected override QueryContainer QueryFluent(QueryContainerDescriptor<Project>
 				.Slop(2)
 				.Name("named_query")
 			);
+
+		//hide
+		[U] public void DeserializeShortForm()
+		{
+			using var stream = new MemoryStream(ShortFormQuery);
+			var query = Client.RequestResponseSerializer.Deserialize<IMatchPhraseQuery>(stream);
+			query.Should().NotBeNull();
+			query.Field.Should().Be(new Field("description"));
+			query.Query.Should().Be("project description");
+		}
 	}
 }

src/Tests/Tests/QueryDsl/FullText/MatchPhrasePrefix/MatchPhrasePrefixUsageTests.cs

@@ -1,4 +1,7 @@
-using Nest;
+using System.IO;
+using Elastic.Xunit.XunitPlumbing;
+using FluentAssertions;
+using Nest;
 using Tests.Core.ManagedElasticsearch.Clusters;
 using Tests.Domain;
 using Tests.Framework.Integration;
@@ -54,5 +57,15 @@ protected override QueryContainer QueryFluent(QueryContainerDescriptor<Project>
 				.Slop(2)
 				.Name("named_query")
 			);
+
+		//hide
+		[U] public void DeserializeShortForm()
+		{
+			using var stream = new MemoryStream(ShortFormQuery);
+			var query = Client.RequestResponseSerializer.Deserialize<IMatchPhrasePrefixQuery>(stream);
+			query.Should().NotBeNull();
+			query.Field.Should().Be(new Field("description"));
+			query.Query.Should().Be("project description");
+		}
 	}
 }

src/Tests/Tests/QueryDsl/QueryDslUsageTestsBase.cs

@@ -1,9 +1,11 @@
 using System;
+using System.Text;
 using System.Threading.Tasks;
 using Elastic.Xunit.XunitPlumbing;
 using Elasticsearch.Net;
 using FluentAssertions;
 using Nest;
+using Newtonsoft.Json;
 using Tests.Core.Client;
 using Tests.Core.Extensions;
 using Tests.Core.ManagedElasticsearch.Clusters;
@@ -20,6 +22,8 @@ public abstract class QueryDslUsageTestsBase
 
 		protected readonly QueryContainer VerbatimQuery = new QueryContainer(new TermQuery { IsVerbatim = true });
 
+		protected byte[] ShortFormQuery => Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(new { description = "project description" }));
+
 		protected QueryDslUsageTestsBase(ReadOnlyCluster cluster, EndpointUsage usage) : base(cluster, usage) { }
 
 		protected virtual ConditionlessWhen ConditionlessWhen => null;

src/Tests/Tests/QueryDsl/TermLevel/Prefix/PrefixQueryUsageTests.cs

@@ -1,9 +1,12 @@
+using System.IO;
+using Elastic.Xunit.XunitPlumbing;
+using FluentAssertions;
 using Nest;
 using Tests.Core.ManagedElasticsearch.Clusters;
 using Tests.Domain;
 using Tests.Framework.Integration;
 
-namespace Tests.QueryDsl.PrefixLevel.Prefix
+namespace Tests.QueryDsl.TermLevel.Prefix
 {
 	public class PrefixQueryUsageTests : QueryDslUsageTestsBase
 	{
@@ -47,5 +50,15 @@ protected override QueryContainer QueryFluent(QueryContainerDescriptor<Project>
 				.Value("proj")
 				.Rewrite(MultiTermQueryRewrite.TopTerms(10))
 			);
+
+		//hide
+		[U] public void DeserializeShortForm()
+		{
+			using var stream = new MemoryStream(ShortFormQuery);
+			var query = Client.RequestResponseSerializer.Deserialize<IPrefixQuery>(stream);
+			query.Should().NotBeNull();
+			query.Field.Should().Be(new Field("description"));
+			query.Value.Should().Be("project description");
+		}
 	}
 }

src/Tests/Tests/QueryDsl/TermLevel/Term/TermQueryUsageTests.cs

@@ -1,3 +1,6 @@
+using System.IO;
+using Elastic.Xunit.XunitPlumbing;
+using FluentAssertions;
 using Nest;
 using Tests.Core.ManagedElasticsearch.Clusters;
 using Tests.Domain;
@@ -44,6 +47,16 @@ protected override QueryContainer QueryFluent(QueryContainerDescriptor<Project>
 				.Field(p => p.Description)
 				.Value("project description")
 			);
+
+		//hide
+		[U] public void DeserializeShortForm()
+		{
+			using var stream = new MemoryStream(ShortFormQuery);
+			var query = Client.RequestResponseSerializer.Deserialize<ITermQuery>(stream);
+			query.Should().NotBeNull();
+			query.Field.Should().Be(new Field("description"));
+			query.Value.Should().Be("project description");
+		}
 	}
 
 	/**[float]