Enum conversion was ignoring the EnumMember attribute

Fixed custom enum conversion to first try to use Json.NET's
StringEnumConverter. If that fails, then fall back to identifying
the appropriate fallback: null, Unknown, then the first enum value.

Author: carolynvs

src/corelib/Serialization/TolerantEnumConverter.cs

@@ -1,19 +1,20 @@
 using System;
 using System.Linq;
 using Newtonsoft.Json;
+using Newtonsoft.Json.Converters;
 
 namespace OpenStack.Serialization
 {
     /// <summary>
     /// Attempts to convert a string to an enum using the following resolution strategy:
-    /// <para>1. Use the name of the enum.</para>
+    /// <para>1. Use StringEnumConverter.</para>
     /// <para>2. Use null if the property is nullable.</para>
     /// <para>3. Use the Unknown enum value.</para>
     /// <para>4. Use the first enum value.</para>
     /// </summary>
     /// <seealso href="http://stackoverflow.com/a/22755077/808818"/>
     /// <exclude />
-    public class TolerantEnumConverter : JsonConverter
+    public class TolerantEnumConverter : StringEnumConverter
     {
         /// <inheritdoc/>
         public override bool CanConvert(Type objectType)
@@ -25,20 +26,19 @@ public override bool CanConvert(Type objectType)
         /// <inheritdoc/>
         public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
         {
+            try
+            {
+                return base.ReadJson(reader, objectType, existingValue, serializer);
+            }
+            catch (JsonSerializationException)
+            {
+
+            }
             bool isNullable = IsNullableType(objectType);
             Type enumType = isNullable ? Nullable.GetUnderlyingType(objectType) : objectType;
 
             string[] names = Enum.GetNames(enumType);
 
-            string enumText = reader.Value.ToString();
-
-            if (!string.IsNullOrEmpty(enumText))
-            {
-                string match = names.FirstOrDefault(n => string.Equals(n, enumText, StringComparison.OrdinalIgnoreCase));
-                if (match != null)
-                    return Enum.Parse(enumType, match);
-            }
-
             if (!isNullable)
             {
                 string defaultName = names.FirstOrDefault(n => string.Equals(n, "Unknown", StringComparison.OrdinalIgnoreCase));

src/testing/unit/Serialization/TolerantEnumConverterTests.cs

@@ -1,4 +1,5 @@
-using Newtonsoft.Json;
+using System.Runtime.Serialization;
+using Newtonsoft.Json;
 using Xunit;
 
 namespace OpenStack.Serialization
@@ -9,7 +10,9 @@ public class TolerantEnumConverterTests
         enum ThingStatus
         {
             Active,
-            Unknown
+            Unknown,
+            [EnumMember(Value = "REMOVE_FAILED")]
+            RemoveFailed
         }
 
         [JsonConverter(typeof(TolerantEnumConverter))]
@@ -22,11 +25,19 @@ enum StuffStatus
         [Fact]
         public void WhenValueIsRecognized_MatchToValue()
         {
-            var result = JsonConvert.DeserializeObject<ThingStatus>("\"Active\"");
+            var result = JsonConvert.DeserializeObject<ThingStatus>("\"ACTIVE\"");
 
             Assert.Equal(ThingStatus.Active, result);
         }
 
+        [Fact]
+        public void WhenAttributedValueIsRecognized_MatchToValue()
+        {
+            var result = JsonConvert.DeserializeObject<ThingStatus>("\"REMOVE_FAILED\"");
+
+            Assert.Equal(ThingStatus.RemoveFailed, result);
+        }
+
         [Fact]
         public void WhenValueIsUnrecognized_MatchToUnknownValue()
         {