chore: removes newtonsoft dependency all together

Author: baywet

test/Microsoft.OpenApi.Hidi.Tests/Microsoft.OpenApi.Hidi.Tests.csproj

@@ -14,7 +14,6 @@
     <PackageReference Include="coverlet.msbuild" Version="6.0.2" PrivateAssets="all" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
     <PackageReference Include="Moq" Version="4.20.72" />
-    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
     <PackageReference Include="xunit" Version="2.9.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" PrivateAssets="all" />
     <PackageReference Include="coverlet.collector" Version="6.0.2" PrivateAssets="all" />

test/Microsoft.OpenApi.Readers.Tests/Microsoft.OpenApi.Readers.Tests.csproj

@@ -19,7 +19,6 @@
         <PackageReference Include="coverlet.msbuild" Version="6.0.2" PrivateAssets="all" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
         <PackageReference Include="FluentAssertions" Version="6.12.2" />
-        <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
         <PackageReference Include="SharpYaml" Version="2.1.1" />
         <PackageReference Include="xunit" Version="2.9.2" />
         <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" PrivateAssets="all" />

test/Microsoft.OpenApi.Tests/Microsoft.OpenApi.Tests.csproj

@@ -13,7 +13,6 @@
     <PackageReference Include="FluentAssertions" Version="6.12.2" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
     <PackageReference Include="Moq" Version="4.20.72" />
-    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
     <PackageReference Include="SharpYaml" Version="2.1.1" />
     <PackageReference Include="Verify.Xunit" Version="28.2.1" />
     <PackageReference Include="xunit" Version="2.9.2" />

test/Microsoft.OpenApi.Tests/Writers/OpenApiJsonWriterTests.cs

@@ -8,12 +8,14 @@
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Text.Encodings.Web;
+using System.Text.Json;
 using System.Text.Json.Nodes;
+using System.Text.Json.Serialization;
 using FluentAssertions;
 using Microsoft.OpenApi.Any;
 using Microsoft.OpenApi.Models;
 using Microsoft.OpenApi.Writers;
-using Newtonsoft.Json;
 using Xunit;
 
 namespace Microsoft.OpenApi.Tests.Writers
@@ -62,9 +64,9 @@ public void WriteStringListAsJsonShouldMatchExpected(string[] stringValues, bool
             writer.WriteEndArray();
             writer.Flush();
 
-            var parsedObject = JsonConvert.DeserializeObject(outputString.GetStringBuilder().ToString());
+            var parsedObject = JsonSerializer.Deserialize<List<string>>(outputString.GetStringBuilder().ToString());
             var expectedObject =
-                JsonConvert.DeserializeObject(JsonConvert.SerializeObject(new List<string>(stringValues)));
+                JsonSerializer.Deserialize<List<string>>(JsonSerializer.Serialize(new List<string>(stringValues)));
 
             // Assert
             parsedObject.Should().BeEquivalentTo(expectedObject);
@@ -222,17 +224,17 @@ private void WriteValueRecursive(OpenApiJsonWriter writer, object value)
         public void WriteMapAsJsonShouldMatchExpected(IDictionary<string, object> inputMap, bool produceTerseOutput)
         {
             // Arrange
-            var outputString = new StringWriter(CultureInfo.InvariantCulture);
+            using var outputString = new StringWriter(CultureInfo.InvariantCulture);
             var writer = new OpenApiJsonWriter(outputString, new() { Terse = produceTerseOutput });
 
             // Act
             WriteValueRecursive(writer, inputMap);
 
-            var parsedObject = JsonConvert.DeserializeObject(outputString.GetStringBuilder().ToString());
-            var expectedObject = JsonConvert.DeserializeObject(JsonConvert.SerializeObject(inputMap));
+            using var parsedObject = JsonDocument.Parse(outputString.GetStringBuilder().ToString());
+            using var expectedObject = JsonDocument.Parse(JsonSerializer.Serialize(inputMap, _jsonSerializerOptions.Value));
 
             // Assert
-            parsedObject.Should().BeEquivalentTo(expectedObject);
+            Assert.True(JsonElement.DeepEquals(parsedObject.RootElement, expectedObject.RootElement));
         }
 
         public static IEnumerable<object[]> WriteDateTimeAsJsonTestCases()
@@ -248,6 +250,57 @@ from shouldBeTerse in shouldProduceTerseOutputValues
                 select new object[] { input, shouldBeTerse };
         }
 
+        public class CustomDateTimeOffsetConverter : JsonConverter<DateTimeOffset>
+        {
+            public CustomDateTimeOffsetConverter(string format)
+            {
+                ArgumentException.ThrowIfNullOrEmpty(format);
+                Format = format;
+            }
+
+            public string Format { get; }
+
+            public override DateTimeOffset Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+            {
+                return DateTime.ParseExact(reader.GetString(), Format, CultureInfo.InvariantCulture);
+            }
+
+            public override void Write(Utf8JsonWriter writer, DateTimeOffset value, JsonSerializerOptions options)
+            {
+                writer.WriteStringValue(value.ToString(Format));
+            }
+        }
+        public class CustomDateTimeConverter : JsonConverter<DateTime>
+        {
+            public CustomDateTimeConverter(string format)
+            {
+                ArgumentException.ThrowIfNullOrEmpty(format);
+                Format = format;
+            }
+
+            public string Format { get; }
+
+            public override DateTime Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+            {
+                return DateTime.ParseExact(reader.GetString(), Format, CultureInfo.InvariantCulture);
+            }
+
+            public override void Write(Utf8JsonWriter writer, DateTime value, JsonSerializerOptions options)
+            {
+                writer.WriteStringValue(value.ToString(Format));
+            }
+        }
+        private static readonly Lazy<JsonSerializerOptions> _jsonSerializerOptions = new(() =>
+        {
+            var options = new JsonSerializerOptions
+            {
+                Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping
+            };
+            options.Converters.Add(new CustomDateTimeOffsetConverter("yyyy-MM-ddTHH:mm:ss.fffffffK"));
+            options.Converters.Add(new CustomDateTimeConverter("yyyy-MM-ddTHH:mm:ss.fffffffK"));
+            return options;
+        });
+
         [Theory]
         [MemberData(nameof(WriteDateTimeAsJsonTestCases))]
         public void WriteDateTimeAsJsonShouldMatchExpected(DateTimeOffset dateTimeOffset, bool produceTerseOutput)
@@ -260,10 +313,7 @@ public void WriteDateTimeAsJsonShouldMatchExpected(DateTimeOffset dateTimeOffset
             writer.WriteValue(dateTimeOffset);
 
             var writtenString = outputString.GetStringBuilder().ToString();
-            var expectedString = JsonConvert.SerializeObject(dateTimeOffset, new JsonSerializerSettings
-            {
-                DateFormatString = "yyyy-MM-ddTHH:mm:ss.fffffffK",
-            });
+            var expectedString = JsonSerializer.Serialize(dateTimeOffset, _jsonSerializerOptions.Value);
 
             // Assert
             writtenString.Should().Be(expectedString);