|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System.Diagnostics;
using System.Text.Json.Serialization;
using SourceGenerators;
namespace System.Text.Json.SourceGeneration
{
/// <summary>
/// Models a property for a generated type.
/// </summary>
/// <remarks>
/// Type needs to be cacheable as a Roslyn incremental value so it must be
///
/// 1) immutable and
/// 2) implement structural (pointwise) equality comparison.
///
/// We can get these properties for free provided that we
///
/// a) define the type as an immutable C# record and
/// b) ensure all nested members are also immutable and implement structural equality.
///
/// When adding new members to the type, please ensure that these properties
/// are satisfied otherwise we risk breaking incremental caching in the source generator!
/// </remarks>
[DebuggerDisplay("Name = {MemberName}, Type = {PropertyType.Name}")]
public sealed record PropertyGenerationSpec
{
/// <summary>
/// The exact name specified in the source code. This might be different
/// from the <see cref="MemberName"/> because source code might be decorated
/// with '@' for reserved keywords, e.g. public string @event { get; set; }
/// </summary>
public required string NameSpecifiedInSourceCode { get; init; }
public required string MemberName { get; init; }
/// <summary>
/// Is this a property or a field?
/// </summary>
public required bool IsProperty { get; init; }
/// <summary>
/// If representing a property, returns true if either the getter or setter are public.
/// </summary>
public required bool IsPublic { get; init; }
public required bool IsVirtual { get; init; }
/// <summary>
/// The property name specified via JsonPropertyNameAttribute, if available.
/// </summary>
public required string? JsonPropertyName { get; init; }
/// <summary>
/// The pre-determined JSON property name, accounting for <see cref="JsonNamingPolicy"/>
/// specified ahead-of-time via <see cref="JsonSourceGenerationOptionsAttribute"/>.
/// Only used in fast-path serialization logic.
/// </summary>
public required string EffectiveJsonPropertyName { get; init; }
/// <summary>
/// The field identifier used for storing JsonEncodedText for use by the fast-path serializer.
/// </summary>
public required string PropertyNameFieldName { get; init; }
/// <summary>
/// Whether the property has a set method.
/// </summary>
public required bool IsReadOnly { get; init; }
/// <summary>
/// Whether the property is marked `required`.
/// </summary>
public required bool IsRequired { get; init; }
/// <summary>
/// The property is marked with JsonRequiredAttribute.
/// </summary>
public required bool HasJsonRequiredAttribute { get; init; }
/// <summary>
/// Whether the property has an init-only set method.
/// </summary>
public required bool IsInitOnlySetter { get; init; }
/// <summary>
/// Whether the property has a public or internal (only usable when JsonIncludeAttribute is specified)
/// getter that can be referenced in generated source code.
/// </summary>
public required bool CanUseGetter { get; init; }
/// <summary>
/// Whether the property has a public or internal (only usable when JsonIncludeAttribute is specified)
/// setter that can be referenced in generated source code.
/// </summary>
public required bool CanUseSetter { get; init; }
/// <summary>
/// Whether the property getter returns a nullable type with a non-nullable annotation.
/// </summary>
public required bool IsGetterNonNullableAnnotation { get; init; }
/// <summary>
/// Whether the property setter accepts a nullable type with a non-nullable annotation.
/// </summary>
public required bool IsSetterNonNullableAnnotation { get; init; }
/// <summary>
/// The <see cref="JsonIgnoreCondition"/> for the property.
/// </summary>
public required JsonIgnoreCondition? DefaultIgnoreCondition { get; init; }
/// <summary>
/// The <see cref="JsonNumberHandling"/> for the property.
/// </summary>
public required JsonNumberHandling? NumberHandling { get; init; }
/// <summary>
/// The <see cref="JsonObjectCreationHandling"/> for the property.
/// </summary>
public required JsonObjectCreationHandling? ObjectCreationHandling { get; init; }
/// <summary>
/// The serialization order of the property.
/// </summary>
public required int Order { get; init; }
/// <summary>
/// Whether the property has the JsonIncludeAttribute. If so, non-public accessors can be used for (de)serialziation.
/// </summary>
public required bool HasJsonInclude { get; init; }
/// <summary>
/// Whether the property can use UnsafeAccessor for its getter/setter.
/// This is true for non-generic types on .NET 8+ and for generic types on .NET 9+
/// (using a generic wrapper class). False when UnsafeAccessorAttribute is not available.
/// </summary>
public required bool CanUseUnsafeAccessors { get; init; }
/// <summary>
/// When <see cref="CanUseUnsafeAccessors"/> is true and the declaring type is generic,
/// contains the FQN of the declaring type using open type parameters
/// (e.g., "global::TestApp.MyGenericType<T>").
/// </summary>
public string? OpenDeclaringTypeFQN { get; init; }
/// <summary>
/// When <see cref="CanUseUnsafeAccessors"/> is true and the declaring type is generic,
/// contains the FQN of the property type using open type parameters
/// (e.g., "T" for a generic property, "string" for a concrete one).
/// </summary>
public string? OpenPropertyTypeFQN { get; init; }
/// <summary>
/// The type parameter names of the generic declaring type (e.g., ["T"]).
/// Null when the declaring type is not generic.
/// </summary>
public ImmutableEquatableArray<string>? DeclaringTypeParameterNames { get; init; }
/// <summary>
/// The combined type parameter constraint clauses of the generic declaring type
/// (e.g., "where T : notnull, global::MyNamespace.MyBase where U : struct").
/// Null when the declaring type is not generic or has no constraints.
/// </summary>
public string? DeclaringTypeParameterConstraintClauses { get; init; }
/// <summary>
/// Whether the property has the JsonExtensionDataAttribute.
/// </summary>
public required bool IsExtensionData { get; init; }
/// <summary>
/// Gets a reference to the property type.
/// </summary>
public required TypeRef PropertyType { get; init; }
/// <summary>
/// Gets a reference to the declaring type of the property.
/// </summary>
public required TypeRef DeclaringType { get; init; }
/// <summary>
/// Design-time specified custom converter type.
/// </summary>
public required TypeRef? ConverterType { get; init; }
/// <summary>
/// Determines if the specified property should be included in the fast-path method body.
/// </summary>
public bool ShouldIncludePropertyForFastPath(ContextGenerationSpec contextSpec)
{
// Discard ignored properties
if (DefaultIgnoreCondition is JsonIgnoreCondition.Always)
{
return false;
}
// Discard properties without getters, unless they have [JsonInclude]
// in which case we use UnsafeAccessor or reflection to read the value.
if (!CanUseGetter && !HasJsonInclude)
{
return false;
}
// Discard fields when JsonInclude or IncludeFields aren't enabled.
if (!IsProperty && !HasJsonInclude && contextSpec.GeneratedOptionsSpec?.IncludeFields != true)
{
return false;
}
// Ignore read-only properties/fields if enabled in configuration.
if (IsReadOnly)
{
if (IsProperty)
{
if (contextSpec.GeneratedOptionsSpec?.IgnoreReadOnlyProperties == true)
{
return false;
}
}
else if (contextSpec.GeneratedOptionsSpec?.IgnoreReadOnlyFields == true)
{
return false;
}
}
return true;
}
}
}
|