better DateTimeConverterUsingDateTimeParse and related tests

ProjBobcat/ProjBobcat.Tests/ClassOrientedTests/JsonConverter/DateTimeConverterUsingDateTimeParseTests.cs

@@ -1,11 +1,6 @@
-using Microsoft.VisualStudio.TestTools.UnitTesting;
-using ProjBobcat.JsonConverter;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
+using ProjBobcat.JsonConverter;
+using System.Globalization;
 using System.Text.Json;
-using System.Threading.Tasks;
 
 namespace ProjBobcat.Tests.ClassOrientedTests.JsonConverter;
 
@@ -17,26 +12,40 @@ public void ReadTest()
     {
         var converter = new DateTimeConverterUsingDateTimeParse();
         var dateTime = DateTime.Now;
-        var jsonData = JsonSerializer.SerializeToUtf8Bytes($"{dateTime}");
-        Utf8JsonReader reader = new Utf8JsonReader(jsonData);
-        Assert.IsTrue(reader.Read());
-        var result = converter.Read(ref reader, typeof(DateTime), JsonSerializerOptions.Default);
-        Assert.AreEqual(dateTime.Ticks, result.Ticks, TimeSpan.FromSeconds(1).Ticks);
-        Assert.IsFalse(reader.Read());
+
+        IEnumerable<(string, bool)> formats = [
+            ("o", true), ("r", true), ("s", false)
+        ];
+        foreach (var (format, toUtc) in formats)
+        {
+            foreach (var culture in CultureInfo.GetCultures(CultureTypes.AllCultures))
+            {
+                var modifiedTime = toUtc ? dateTime.ToUniversalTime() : dateTime;
+                var jsonData = JsonSerializer.SerializeToUtf8Bytes(
+                    modifiedTime.ToString(format, culture));
+
+                Utf8JsonReader reader = new Utf8JsonReader(jsonData);
+                Assert.IsTrue(reader.Read());
+                var result = converter.Read(ref reader, typeof(DateTime), JsonSerializerOptions.Default);
+                Assert.IsFalse(reader.Read());
+
+                Assert.AreEqual(dateTime.Ticks, result.Ticks, TimeSpan.FromSeconds(1).Ticks);
+            }
+        }
     }
 
     [TestMethod()]
     public void WriteTest()
     {
         var converter = new DateTimeConverterUsingDateTimeParse();
-        using var stream = new MemoryStream();
         var dateTime = DateTime.Now;
+
+        using var stream = new MemoryStream();
         using (var writer = new Utf8JsonWriter(stream))
             converter.Write(writer, dateTime, JsonSerializerOptions.Default);
-
         var actual = stream.ToArray();
-        var expected = JsonSerializer.SerializeToUtf8Bytes($"{dateTime}");
-#warning different result in different culture. is this really expected?
+
+        var expected = JsonSerializer.SerializeToUtf8Bytes(dateTime);
         CollectionAssert.AreEqual(expected, actual);
     }
-}
+}

ProjBobcat/ProjBobcat/JsonConverter/DateTimeConverterUsingDateTimeParse.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Diagnostics;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 
@@ -9,12 +8,17 @@ public class DateTimeConverterUsingDateTimeParse : JsonConverter<DateTime>
 {
     public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
     {
-        Debug.Assert(typeToConvert == typeof(DateTime));
+        if (typeToConvert != typeof(DateTime))
+            throw new ArgumentException(
+                $"{nameof(DateTimeConverterUsingDateTimeParse)} cannot deserialize " +
+                $"an object of {typeToConvert.Name}", 
+                nameof(typeToConvert));
+
         return DateTime.Parse(reader.GetString() ?? string.Empty);
     }
 
     public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
     {
-        writer.WriteStringValue(value.ToString());
+        writer.WriteStringValue(value);
     }
 }