Search SDK: Fix bug that prevented infinite double values from deserializing

src/Search/Microsoft.Azure.Search/Customizations/Serialization/Private/DoubleConverter.cs

@@ -0,0 +1,72 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for
+// license information.
+
+namespace Microsoft.Azure.Search.Serialization
+{
+    using System;
+    using System.Globalization;
+    using System.Reflection;
+    using Newtonsoft.Json;
+
+    /// <summary>
+    /// Serializes doubles to and from the OData wire format.
+    /// </summary>
+    internal class DoubleConverter : JsonConverter
+    {
+        private const string ODataNegativeInfinity = "-INF";
+        private const string ODataPositiveInfinity = "INF";
+
+        public override bool CanConvert(Type objectType) =>
+            typeof(double?).GetTypeInfo().IsAssignableFrom(objectType.GetTypeInfo()) ||
+            typeof(double).GetTypeInfo().IsAssignableFrom(objectType.GetTypeInfo());
+
+        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
+        {
+            if (reader.TokenType == JsonToken.Null)
+            {
+                return null;
+            }
+
+            if (reader.TokenType == JsonToken.String)
+            {
+                string strValue = (string)reader.Value;
+
+                switch (strValue)
+                {
+                    case ODataPositiveInfinity: return Double.PositiveInfinity;
+                    case ODataNegativeInfinity: return Double.NegativeInfinity;
+                    default: return Double.Parse(strValue, CultureInfo.InvariantCulture);
+                }
+            }
+
+            // We can't use a direct cast because sometimes we get integers from the reader.
+            return Convert.ToDouble(reader.Value);
+        }
+
+        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
+        {
+            if (value == null)
+            {
+                writer.WriteNull();
+            }
+            else
+            {
+                double doubleValue = (double)value;
+
+                if (Double.IsNegativeInfinity(doubleValue))
+                {
+                    writer.WriteValue(ODataNegativeInfinity);
+                }
+                else if (Double.IsPositiveInfinity(doubleValue))
+                {
+                    writer.WriteValue(ODataPositiveInfinity);
+                }
+                else
+                {
+                    writer.WriteValue(doubleValue);
+                }
+            }
+        }
+    }
+}

src/Search/Microsoft.Azure.Search/Customizations/Serialization/Private/JsonUtility.cs

@@ -48,6 +48,7 @@ private static JsonSerializerSettings CreateSerializerSettings<T>(
             settings.Converters.Add(new GeographyPointConverter());
             settings.Converters.Add(new IndexActionConverter<T>());
             settings.Converters.Add(new DateTimeConverter());
+            settings.Converters.Add(new DoubleConverter());
             settings.NullValueHandling = NullValueHandling.Ignore;
 
             if (useCamelCase)
@@ -72,6 +73,7 @@ private static JsonSerializerSettings CreateDeserializerSettings<TSearchResult,
             settings.Converters.Add(new GeographyPointConverter());
             settings.Converters.Add(new DocumentConverter());
             settings.Converters.Add(new DateTimeConverter());
+            settings.Converters.Add(new DoubleConverter());
             settings.Converters.Add(new SearchResultConverter<TSearchResult, TDoc>());
             settings.Converters.Add(new SuggestResultConverter<TSuggestResult, TDoc>());
             settings.DateParseHandling = DateParseHandling.DateTimeOffset;