Fixes float and double serialization for cultures that use comma as decimal separator (#17)

pt-BR for instance uses comma instead of dot as decimal separator

Author: gustavosantos-kazoo

Serialization.NET/Segment/Serialization/JsonElement.cs

@@ -1,6 +1,7 @@
 using System.Collections;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 
 #if NETSTANDARD2_0
@@ -61,6 +62,19 @@ public static implicit operator JsonPrimitive(string value)
 
         public static JsonPrimitive Create(object value, bool isString)
         {
+            if (value is string s)
+            {
+                if (float.TryParse(s, out var f))
+                {
+                    return new JsonLiteral(f, isString);
+                }
+
+                if (double.TryParse(s, out var d))
+                {
+                    return new JsonLiteral(d, isString);
+                }
+            }
+
             return new JsonLiteral(value, isString);
         }
     }
@@ -74,7 +88,19 @@ internal class JsonLiteral : JsonPrimitive
         internal JsonLiteral(object body, bool isString)
         {
             IsString = isString;
-            Content = body.ToString();
+
+            switch (body)
+            {
+                case float f:
+                    Content = f.ToString(CultureInfo.InvariantCulture);
+                    break;
+                case double d:
+                    Content = d.ToString(CultureInfo.InvariantCulture);
+                    break;
+                default:
+                    Content = body.ToString();
+                    break;
+            }
         }
 
         public override string ToString()

Tests/DecimalNumberSerializationTest.cs

@@ -0,0 +1,47 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using Segment.Serialization;
+using Xunit;
+
+namespace Tests
+{
+    public class DecimalNumberSerializationTest
+    {
+        private class CurrentCultureScope : IDisposable
+        {
+            private readonly CultureInfo _originalCurrentCulture;
+
+            public CurrentCultureScope(CultureInfo cultureInfo)
+            {
+                _originalCurrentCulture = CultureInfo.CurrentCulture;
+                CultureInfo.CurrentCulture = cultureInfo;
+            }
+
+            public void Dispose()
+            {
+                CultureInfo.CurrentCulture = _originalCurrentCulture;
+            }
+        }
+
+        [Fact]
+        public void TestDecimalNumberSerializationForAllCultures()
+        {
+            var eventParameters = new Dictionary<string, object> { { "FloatNumber", 1.23f } };
+
+            foreach (var cultureInfo in CultureInfo.GetCultures(CultureTypes.AllCultures))
+            {
+                using (new CurrentCultureScope(cultureInfo))
+                {
+                    var eventParametersJson = JsonUtility.ToJson(eventParameters); // This call exist inside Segment.Analytics.Analytics::Track<T>
+                    var jsonObject = JsonUtility.FromJson<JsonObject>(eventParametersJson); // This call exist inside Segment.Analytics.Analytics::Track<T>
+                    var payloadJson = JsonUtility.ToJson(jsonObject); // Later, when dispatching the event to the analytics server, jsonObject gets serialized as JSON. If any float was serialized under pt-BR culture (which uses comma as a decimal separator), the JSON will be malformed and rejected by server.
+                    Assert.True(payloadJson != null);
+                    var payloadHashSet = new HashSet<char>(payloadJson); // Straight character comparison without culture info
+                    Assert.Contains('.', payloadHashSet);
+                    Assert.DoesNotContain(',', payloadHashSet);
+                }
+            }
+        }
+    }
+}