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Merged
merged 1 commit into from
Aug 18, 2021
Merged

Support reference type custom converters in source gen #57592

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18 changes: 16 additions & 2 deletions src/libraries/System.Text.Json/gen/JsonSourceGenerator.Emitter.cs
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Expand Up @@ -277,10 +277,12 @@ private string GenerateForTypeWithUnknownConverter(TypeGenerationSpec typeMetada
string typeCompilableName = typeMetadata.TypeRef;
string typeFriendlyName = typeMetadata.TypeInfoPropertyName;

StringBuilder sb = new();
string metadataInitSource;

// TODO (https://github.com/dotnet/runtime/issues/52218): consider moving this verification source to common helper.
string metadataInitSource = $@"{JsonConverterTypeRef} converter = {typeMetadata.ConverterInstantiationLogic};
if (typeMetadata.IsValueType)
{
metadataInitSource = $@"{JsonConverterTypeRef} converter = {typeMetadata.ConverterInstantiationLogic};
{TypeTypeRef} typeToConvert = typeof({typeCompilableName});
if (!converter.CanConvert(typeToConvert))
{{
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@eiriktsarpalis eiriktsarpalis Aug 18, 2021 •
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Nit: given that there is a some amount of duplication between the ref type and value type generated code, is there any way we could splice in the nullable check, i.e some thing like

if (!converter.CanConvert(typeToConvert))
{{
     {!typeof(T).IsValueType ? "" : EmitNullableTypeHandling()}

?

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That is a fair suggestion, and I'll leave it up to @layomia to change it if desired. However, in this case I think it is more readable\understandable to have separate ifs since the amount of emit duplication is only 5 LOC or so.

Expand Down Expand Up @@ -309,6 +311,18 @@ private string GenerateForTypeWithUnknownConverter(TypeGenerationSpec typeMetada
}}

_{typeFriendlyName} = {JsonMetadataServicesTypeRef}.{GetCreateValueInfoMethodRef(typeCompilableName)}({OptionsInstanceVariableName}, converter);";
}
else
{
metadataInitSource = $@"{JsonConverterTypeRef} converter = {typeMetadata.ConverterInstantiationLogic};
{TypeTypeRef} typeToConvert = typeof({typeCompilableName});
if (!converter.CanConvert(typeToConvert))
{{
throw new {InvalidOperationExceptionTypeRef}($""The converter '{{converter.GetType()}}' is not compatible with the type '{{typeToConvert}}'."");
}}

_{typeFriendlyName} = {JsonMetadataServicesTypeRef}.{GetCreateValueInfoMethodRef(typeCompilableName)}({OptionsInstanceVariableName}, converter);";
}

return GenerateForType(typeMetadata, metadataInitSource);
}
Expand Down
4 changes: 4 additions & 0 deletions ...ibraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/ContextClasses.cs
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Expand Up @@ -29,6 +29,10 @@ public interface ITestContext
public JsonTypeInfo<object[]> ObjectArray { get; }
public JsonTypeInfo<string> String { get; }
public JsonTypeInfo<RealWorldContextTests.ClassWithEnumAndNullable> ClassWithEnumAndNullable { get; }
public JsonTypeInfo<ClassWithCustomConverter> ClassWithCustomConverter { get; }
public JsonTypeInfo<StructWithCustomConverter> StructWithCustomConverter { get; }
public JsonTypeInfo<ClassWithBadCustomConverter> ClassWithBadCustomConverter { get; }
public JsonTypeInfo<StructWithBadCustomConverter> StructWithBadCustomConverter { get; }
}

internal partial class JsonContext : JsonSerializerContext
Expand Down
8 changes: 8 additions & 0 deletions ...son/tests/System.Text.Json.SourceGeneration.Tests/MetadataAndSerializationContextTests.cs
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Expand Up @@ -27,6 +27,10 @@ namespace System.Text.Json.SourceGeneration.Tests
[JsonSerializable(typeof(object[]))]
[JsonSerializable(typeof(string))]
[JsonSerializable(typeof(RealWorldContextTests.ClassWithEnumAndNullable))]
[JsonSerializable(typeof(ClassWithCustomConverter))]
[JsonSerializable(typeof(StructWithCustomConverter))]
[JsonSerializable(typeof(ClassWithBadCustomConverter))]
[JsonSerializable(typeof(StructWithBadCustomConverter))]
internal partial class MetadataAndSerializationContext : JsonSerializerContext, ITestContext
{
}
Expand Down Expand Up @@ -58,6 +62,10 @@ public override void EnsureFastPathGeneratedAsExpected()
Assert.Null(MetadataAndSerializationContext.Default.ObjectArray.Serialize);
Assert.Null(MetadataAndSerializationContext.Default.String.Serialize);
Assert.NotNull(MetadataAndSerializationContext.Default.ClassWithEnumAndNullable.Serialize);
Assert.NotNull(MetadataAndSerializationContext.Default.ClassWithCustomConverter);
Assert.NotNull(MetadataAndSerializationContext.Default.StructWithCustomConverter);
Assert.Throws<InvalidOperationException>(() => MetadataAndSerializationContext.Default.ClassWithBadCustomConverter);
Assert.Throws<InvalidOperationException>(() => MetadataAndSerializationContext.Default.StructWithBadCustomConverter);
}
}
}
18 changes: 18 additions & 0 deletions ...es/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/MetadataContextTests.cs
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Expand Up @@ -26,6 +26,12 @@ namespace System.Text.Json.SourceGeneration.Tests
[JsonSerializable(typeof(object[]), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(string), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(RealWorldContextTests.ClassWithEnumAndNullable), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(ClassWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(StructWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(ClassWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(StructWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(ClassWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(StructWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata)]
internal partial class MetadataWithPerTypeAttributeContext : JsonSerializerContext, ITestContext
{
}
Expand Down Expand Up @@ -55,6 +61,10 @@ public override void EnsureFastPathGeneratedAsExpected()
Assert.Null(MetadataWithPerTypeAttributeContext.Default.ObjectArray.Serialize);
Assert.Null(MetadataWithPerTypeAttributeContext.Default.String.Serialize);
Assert.Null(MetadataWithPerTypeAttributeContext.Default.ClassWithEnumAndNullable.Serialize);
Assert.Null(MetadataWithPerTypeAttributeContext.Default.ClassWithCustomConverter.Serialize);
Assert.Null(MetadataWithPerTypeAttributeContext.Default.StructWithCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => MetadataWithPerTypeAttributeContext.Default.ClassWithBadCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => MetadataWithPerTypeAttributeContext.Default.StructWithBadCustomConverter.Serialize);
}
}

Expand All @@ -79,6 +89,10 @@ public override void EnsureFastPathGeneratedAsExpected()
[JsonSerializable(typeof(object[]))]
[JsonSerializable(typeof(string))]
[JsonSerializable(typeof(RealWorldContextTests.ClassWithEnumAndNullable))]
[JsonSerializable(typeof(ClassWithCustomConverter))]
[JsonSerializable(typeof(StructWithCustomConverter))]
[JsonSerializable(typeof(ClassWithBadCustomConverter))]
[JsonSerializable(typeof(StructWithBadCustomConverter))]
internal partial class MetadataContext : JsonSerializerContext, ITestContext
{
}
Expand Down Expand Up @@ -110,6 +124,10 @@ public override void EnsureFastPathGeneratedAsExpected()
Assert.Null(MetadataContext.Default.ObjectArray.Serialize);
Assert.Null(MetadataContext.Default.String.Serialize);
Assert.Null(MetadataContext.Default.ClassWithEnumAndNullable.Serialize);
Assert.Null(MetadataContext.Default.ClassWithCustomConverter.Serialize);
Assert.Null(MetadataContext.Default.StructWithCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => MetadataContext.Default.ClassWithBadCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => MetadataContext.Default.StructWithBadCustomConverter.Serialize);
}
}
}
8 changes: 8 additions & 0 deletions ...s/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/MixedModeContextTests.cs
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Expand Up @@ -26,6 +26,10 @@ namespace System.Text.Json.SourceGeneration.Tests
[JsonSerializable(typeof(object[]), GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(string), GenerationMode = JsonSourceGenerationMode.Metadata | JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(RealWorldContextTests.ClassWithEnumAndNullable), GenerationMode = JsonSourceGenerationMode.Metadata | JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(ClassWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata | JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(StructWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata | JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(ClassWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata | JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(StructWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Metadata | JsonSourceGenerationMode.Serialization)]
internal partial class MixedModeContext : JsonSerializerContext, ITestContext
{
}
Expand Down Expand Up @@ -56,6 +60,10 @@ public override void EnsureFastPathGeneratedAsExpected()
Assert.Null(MixedModeContext.Default.ObjectArray.Serialize);
Assert.Null(MixedModeContext.Default.String.Serialize);
Assert.NotNull(MixedModeContext.Default.ClassWithEnumAndNullable.Serialize);
Assert.Null(MixedModeContext.Default.ClassWithCustomConverter.Serialize);
Assert.Null(MixedModeContext.Default.StructWithCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => MixedModeContext.Default.ClassWithBadCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => MixedModeContext.Default.StructWithBadCustomConverter.Serialize);
}

[Fact]
Expand Down
58 changes: 58 additions & 0 deletions ...s/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/RealWorldContextTests.cs
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Expand Up @@ -110,6 +110,64 @@ public virtual void RoundTripTypeNameClash()
VerifyRepeatedLocation(expected, obj);
}

[Fact]
public virtual void RoundTripWithCustomConverter_Class()
{
const string Json = "{\"MyInt\":142}";

ClassWithCustomConverter obj = new ClassWithCustomConverter()
{
MyInt = 42
};

string json = JsonSerializer.Serialize(obj, DefaultContext.ClassWithCustomConverter);
Assert.Equal(Json, json);

obj = JsonSerializer.Deserialize(Json, DefaultContext.ClassWithCustomConverter);
Assert.Equal(42, obj.MyInt);
}

[Fact]
public virtual void RoundTripWithCustomConverter_Struct()
{
const string Json = "{\"MyInt\":142}";

StructWithCustomConverter obj = new StructWithCustomConverter()
{
MyInt = 42
};

string json = JsonSerializer.Serialize(obj, DefaultContext.StructWithCustomConverter);
Assert.Equal(Json, json);

obj = JsonSerializer.Deserialize(Json, DefaultContext.StructWithCustomConverter);
Assert.Equal(42, obj.MyInt);
}

[Fact]
public virtual void BadCustomConverter_Class()
{
const string Json = "{\"MyInt\":142}";

Assert.Throws<InvalidOperationException>(() =>
JsonSerializer.Serialize(new ClassWithBadCustomConverter(), DefaultContext.ClassWithBadCustomConverter));

Assert.Throws<InvalidOperationException>(() =>
JsonSerializer.Deserialize(Json, DefaultContext.ClassWithBadCustomConverter));
}

[Fact]
public virtual void BadCustomConverter_Struct()
{
const string Json = "{\"MyInt\":142}";

Assert.Throws<InvalidOperationException>(() =>
JsonSerializer.Serialize(new StructWithBadCustomConverter(), DefaultContext.StructWithBadCustomConverter));

Assert.Throws<InvalidOperationException>(() =>
JsonSerializer.Deserialize(Json, DefaultContext.StructWithBadCustomConverter));
}

protected static Location CreateLocation()
{
return new Location
Expand Down
22 changes: 22 additions & 0 deletions ...stem.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/SerializationContextTests.cs
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Expand Up @@ -27,6 +27,10 @@ namespace System.Text.Json.SourceGeneration.Tests
[JsonSerializable(typeof(object[]))]
[JsonSerializable(typeof(string))]
[JsonSerializable(typeof(RealWorldContextTests.ClassWithEnumAndNullable))]
[JsonSerializable(typeof(ClassWithCustomConverter))]
[JsonSerializable(typeof(StructWithCustomConverter))]
[JsonSerializable(typeof(ClassWithBadCustomConverter))]
[JsonSerializable(typeof(StructWithBadCustomConverter))]
internal partial class SerializationContext : JsonSerializerContext, ITestContext
{
}
Expand All @@ -51,6 +55,12 @@ internal partial class SerializationContext : JsonSerializerContext, ITestContex
[JsonSerializable(typeof(object[]), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(string), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(RealWorldContextTests.ClassWithEnumAndNullable), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(ClassWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(StructWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(ClassWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(StructWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(ClassWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(StructWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
internal partial class SerializationWithPerTypeAttributeContext : JsonSerializerContext, ITestContext
{
}
Expand All @@ -76,6 +86,10 @@ internal partial class SerializationWithPerTypeAttributeContext : JsonSerializer
[JsonSerializable(typeof(object[]), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(string), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(RealWorldContextTests.ClassWithEnumAndNullable), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(ClassWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(StructWithCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(ClassWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
[JsonSerializable(typeof(StructWithBadCustomConverter), GenerationMode = JsonSourceGenerationMode.Serialization)]
internal partial class SerializationContextWithCamelCase : JsonSerializerContext, ITestContext
{
}
Expand Down Expand Up @@ -112,6 +126,10 @@ public override void EnsureFastPathGeneratedAsExpected()
Assert.Null(SerializationContext.Default.ObjectArray.Serialize);
Assert.Null(SerializationContext.Default.String.Serialize);
Assert.NotNull(SerializationContext.Default.ClassWithEnumAndNullable.Serialize);
Assert.Null(SerializationContext.Default.ClassWithCustomConverter.Serialize);
Assert.Null(SerializationContext.Default.StructWithCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => SerializationContext.Default.ClassWithBadCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => SerializationContext.Default.StructWithBadCustomConverter.Serialize);
}

[Fact]
Expand Down Expand Up @@ -370,6 +388,10 @@ public override void EnsureFastPathGeneratedAsExpected()
Assert.Null(SerializationWithPerTypeAttributeContext.Default.ObjectArray.Serialize);
Assert.Null(SerializationWithPerTypeAttributeContext.Default.String.Serialize);
Assert.NotNull(SerializationWithPerTypeAttributeContext.Default.ClassWithEnumAndNullable.Serialize);
Assert.Null(SerializationWithPerTypeAttributeContext.Default.ClassWithCustomConverter.Serialize);
Assert.Null(SerializationWithPerTypeAttributeContext.Default.StructWithCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => SerializationWithPerTypeAttributeContext.Default.ClassWithBadCustomConverter.Serialize);
Assert.Throws<InvalidOperationException>(() => SerializationWithPerTypeAttributeContext.Default.StructWithBadCustomConverter.Serialize);
}
}
}
106 changes: 106 additions & 0 deletions src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/TestClasses.cs
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Expand Up @@ -151,4 +151,110 @@ public class JsonMessage
}

internal struct MyStruct { }

/// <summary>
/// Custom converter that adds\substract 100 from MyIntProperty.
/// </summary>
public class CustomConverterForClass : JsonConverter<ClassWithCustomConverter>
{
public override ClassWithCustomConverter Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
{
if (reader.TokenType != JsonTokenType.StartObject)
{
throw new JsonException("No StartObject");
}

ClassWithCustomConverter obj = new();

reader.Read();
if (reader.TokenType != JsonTokenType.PropertyName &&
reader.GetString() != "MyInt")
{
throw new JsonException("Wrong property name");
}

reader.Read();
obj.MyInt = reader.GetInt32() - 100;

reader.Read();
if (reader.TokenType != JsonTokenType.EndObject)
{
throw new JsonException("No EndObject");
}

return obj;
}

public override void Write(Utf8JsonWriter writer, ClassWithCustomConverter value, JsonSerializerOptions options)
{
writer.WriteStartObject();
writer.WriteNumber(nameof(ClassWithCustomConverter.MyInt), value.MyInt + 100);
writer.WriteEndObject();
}
}

[JsonConverter(typeof(CustomConverterForClass))]
public class ClassWithCustomConverter
{
public int MyInt { get; set; }
}

[JsonConverter(typeof(CustomConverterForStruct))] // Invalid
public struct ClassWithBadCustomConverter
{
public int MyInt { get; set; }
}

/// <summary>
/// Custom converter that adds\substract 100 from MyIntProperty.
/// </summary>
public class CustomConverterForStruct : JsonConverter<StructWithCustomConverter>
{
public override StructWithCustomConverter Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
{
if (reader.TokenType != JsonTokenType.StartObject)
{
throw new JsonException("No StartObject");
}

StructWithCustomConverter obj = new();

reader.Read();
if (reader.TokenType != JsonTokenType.PropertyName &&
reader.GetString() != "MyInt")
{
throw new JsonException("Wrong property name");
}

reader.Read();
obj.MyInt = reader.GetInt32() - 100;

reader.Read();
if (reader.TokenType != JsonTokenType.EndObject)
{
throw new JsonException("No EndObject");
}

return obj;
}

public override void Write(Utf8JsonWriter writer, StructWithCustomConverter value, JsonSerializerOptions options)
{
writer.WriteStartObject();
writer.WriteNumber(nameof(StructWithCustomConverter.MyInt), value.MyInt + 100);
writer.WriteEndObject();
}
}

[JsonConverter(typeof(CustomConverterForStruct))]
public struct StructWithCustomConverter
{
public int MyInt { get; set; }
}

[JsonConverter(typeof(CustomConverterForClass))] // Invalid
public struct StructWithBadCustomConverter
{
public int MyInt { get; set; }
}
}