DynamicProxyMetaObject<T>
using System;
using System.Collections.Generic;
using System.Dynamic;
using System.Linq;
using System.Linq.Expressions;
using System.Runtime.CompilerServices;
namespace Newtonsoft.Json.Utilities
{
[System.Runtime.CompilerServices.NullableContext(1)]
[System.Runtime.CompilerServices.Nullable(0)]
internal sealed class DynamicProxyMetaObject<[System.Runtime.CompilerServices.Nullable(2)] T> : DynamicMetaObject
{
[System.Runtime.CompilerServices.NullableContext(0)]
private delegate DynamicMetaObject Fallback ([System.Runtime.CompilerServices.Nullable(2)] DynamicMetaObject errorSuggestion);
[System.Runtime.CompilerServices.Nullable(0)]
private sealed class GetBinderAdapter : GetMemberBinder
{
internal GetBinderAdapter(InvokeMemberBinder binder)
: base(binder.Name, binder.IgnoreCase)
{
}
public override DynamicMetaObject FallbackGetMember(DynamicMetaObject target, [System.Runtime.CompilerServices.Nullable(2)] DynamicMetaObject errorSuggestion)
{
throw new NotSupportedException();
}
}
private readonly DynamicProxy<T> _proxy;
private static Expression[] NoArgs => CollectionUtils.ArrayEmpty<Expression>();
internal DynamicProxyMetaObject(Expression expression, T value, DynamicProxy<T> proxy)
: base(expression, BindingRestrictions.Empty, value)
{
_proxy = proxy;
}
private bool IsOverridden(string method)
{
return ReflectionUtils.IsMethodOverridden(_proxy.GetType(), typeof(DynamicProxy<T>), method);
}
public override DynamicMetaObject BindGetMember(GetMemberBinder binder)
{
if (!IsOverridden("TryGetMember"))
return base.BindGetMember(binder);
return CallMethodWithResult("TryGetMember", binder, NoArgs, (DynamicMetaObject e) => binder.FallbackGetMember(this, e), null);
}
public override DynamicMetaObject BindSetMember(SetMemberBinder binder, DynamicMetaObject value)
{
if (!IsOverridden("TrySetMember"))
return base.BindSetMember(binder, value);
return CallMethodReturnLast("TrySetMember", binder, GetArgs(value), (DynamicMetaObject e) => binder.FallbackSetMember(this, value, e));
}
public override DynamicMetaObject BindDeleteMember(DeleteMemberBinder binder)
{
if (!IsOverridden("TryDeleteMember"))
return base.BindDeleteMember(binder);
return CallMethodNoResult("TryDeleteMember", binder, NoArgs, (DynamicMetaObject e) => binder.FallbackDeleteMember(this, e));
}
public override DynamicMetaObject BindConvert(ConvertBinder binder)
{
if (!IsOverridden("TryConvert"))
return base.BindConvert(binder);
return CallMethodWithResult("TryConvert", binder, NoArgs, (DynamicMetaObject e) => binder.FallbackConvert(this, e), null);
}
public override DynamicMetaObject BindInvokeMember(InvokeMemberBinder binder, DynamicMetaObject[] args)
{
if (!IsOverridden("TryInvokeMember"))
return base.BindInvokeMember(binder, args);
Fallback fallback = (DynamicMetaObject e) => binder.FallbackInvokeMember(this, args, e);
return BuildCallMethodWithResult("TryInvokeMember", binder, GetArgArray(args), BuildCallMethodWithResult("TryGetMember", new GetBinderAdapter(binder), NoArgs, fallback(null), (DynamicMetaObject e) => binder.FallbackInvoke(e, args, null)), null);
}
public override DynamicMetaObject BindCreateInstance(CreateInstanceBinder binder, DynamicMetaObject[] args)
{
if (!IsOverridden("TryCreateInstance"))
return base.BindCreateInstance(binder, args);
return CallMethodWithResult("TryCreateInstance", binder, GetArgArray(args), (DynamicMetaObject e) => binder.FallbackCreateInstance(this, args, e), null);
}
public override DynamicMetaObject BindInvoke(InvokeBinder binder, DynamicMetaObject[] args)
{
if (!IsOverridden("TryInvoke"))
return base.BindInvoke(binder, args);
return CallMethodWithResult("TryInvoke", binder, GetArgArray(args), (DynamicMetaObject e) => binder.FallbackInvoke(this, args, e), null);
}
public override DynamicMetaObject BindBinaryOperation(BinaryOperationBinder binder, DynamicMetaObject arg)
{
if (!IsOverridden("TryBinaryOperation"))
return base.BindBinaryOperation(binder, arg);
return CallMethodWithResult("TryBinaryOperation", binder, GetArgs(arg), (DynamicMetaObject e) => binder.FallbackBinaryOperation(this, arg, e), null);
}
public override DynamicMetaObject BindUnaryOperation(UnaryOperationBinder binder)
{
if (!IsOverridden("TryUnaryOperation"))
return base.BindUnaryOperation(binder);
return CallMethodWithResult("TryUnaryOperation", binder, NoArgs, (DynamicMetaObject e) => binder.FallbackUnaryOperation(this, e), null);
}
public override DynamicMetaObject BindGetIndex(GetIndexBinder binder, DynamicMetaObject[] indexes)
{
if (!IsOverridden("TryGetIndex"))
return base.BindGetIndex(binder, indexes);
return CallMethodWithResult("TryGetIndex", binder, GetArgArray(indexes), (DynamicMetaObject e) => binder.FallbackGetIndex(this, indexes, e), null);
}
public override DynamicMetaObject BindSetIndex(SetIndexBinder binder, DynamicMetaObject[] indexes, DynamicMetaObject value)
{
if (!IsOverridden("TrySetIndex"))
return base.BindSetIndex(binder, indexes, value);
return CallMethodReturnLast("TrySetIndex", binder, GetArgArray(indexes, value), (DynamicMetaObject e) => binder.FallbackSetIndex(this, indexes, value, e));
}
public override DynamicMetaObject BindDeleteIndex(DeleteIndexBinder binder, DynamicMetaObject[] indexes)
{
if (!IsOverridden("TryDeleteIndex"))
return base.BindDeleteIndex(binder, indexes);
return CallMethodNoResult("TryDeleteIndex", binder, GetArgArray(indexes), (DynamicMetaObject e) => binder.FallbackDeleteIndex(this, indexes, e));
}
private static IEnumerable<Expression> GetArgs(params DynamicMetaObject[] args)
{
return Enumerable.Select<DynamicMetaObject, Expression>((IEnumerable<DynamicMetaObject>)args, (Func<DynamicMetaObject, Expression>)delegate(DynamicMetaObject arg) {
Expression expression = arg.Expression;
if (!expression.Type.IsValueType())
return expression;
return Expression.Convert(expression, typeof(object));
});
}
private static Expression[] GetArgArray(DynamicMetaObject[] args)
{
return new NewArrayExpression[1] {
Expression.NewArrayInit(typeof(object), GetArgs(args))
};
}
private static Expression[] GetArgArray(DynamicMetaObject[] args, DynamicMetaObject value)
{
Expression expression = value.Expression;
return new Expression[2] {
Expression.NewArrayInit(typeof(object), GetArgs(args)),
expression.Type.IsValueType() ? Expression.Convert(expression, typeof(object)) : expression
};
}
private static ConstantExpression Constant(DynamicMetaObjectBinder binder)
{
Type type = binder.GetType();
while (!type.IsVisible()) {
type = type.BaseType();
}
return Expression.Constant(binder, type);
}
private DynamicMetaObject CallMethodWithResult(string methodName, DynamicMetaObjectBinder binder, IEnumerable<Expression> args, [System.Runtime.CompilerServices.Nullable(new byte[] {
1,
0
})] Fallback fallback, [System.Runtime.CompilerServices.Nullable(new byte[] {
2,
0
})] Fallback fallbackInvoke = null)
{
DynamicMetaObject fallbackResult = fallback(null);
return BuildCallMethodWithResult(methodName, binder, args, fallbackResult, fallbackInvoke);
}
private DynamicMetaObject BuildCallMethodWithResult(string methodName, DynamicMetaObjectBinder binder, IEnumerable<Expression> args, DynamicMetaObject fallbackResult, [System.Runtime.CompilerServices.Nullable(new byte[] {
2,
0
})] Fallback fallbackInvoke)
{
ParameterExpression parameterExpression = Expression.Parameter(typeof(object), null);
IList<Expression> list = new List<Expression>();
list.Add(Expression.Convert(base.Expression, typeof(T)));
list.Add(Constant(binder));
CollectionUtils.AddRange<Expression>(list, args);
list.Add(parameterExpression);
DynamicMetaObject dynamicMetaObject = new DynamicMetaObject(parameterExpression, BindingRestrictions.Empty);
if (binder.ReturnType != typeof(object))
dynamicMetaObject = new DynamicMetaObject(Expression.Convert(dynamicMetaObject.Expression, binder.ReturnType), dynamicMetaObject.Restrictions);
if (fallbackInvoke != null)
dynamicMetaObject = fallbackInvoke(dynamicMetaObject);
return new DynamicMetaObject(Expression.Block(new ParameterExpression[1] {
parameterExpression
}, Expression.Condition(Expression.Call(Expression.Constant(_proxy), typeof(DynamicProxy<T>).GetMethod(methodName), list), dynamicMetaObject.Expression, fallbackResult.Expression, binder.ReturnType)), GetRestrictions().Merge(dynamicMetaObject.Restrictions).Merge(fallbackResult.Restrictions));
}
private DynamicMetaObject CallMethodReturnLast(string methodName, DynamicMetaObjectBinder binder, IEnumerable<Expression> args, [System.Runtime.CompilerServices.Nullable(new byte[] {
1,
0
})] Fallback fallback)
{
DynamicMetaObject dynamicMetaObject = fallback(null);
ParameterExpression parameterExpression = Expression.Parameter(typeof(object), null);
IList<Expression> list = new List<Expression>();
list.Add(Expression.Convert(base.Expression, typeof(T)));
list.Add(Constant(binder));
CollectionUtils.AddRange<Expression>(list, args);
list[list.Count - 1] = Expression.Assign(parameterExpression, list[list.Count - 1]);
return new DynamicMetaObject(Expression.Block(new ParameterExpression[1] {
parameterExpression
}, Expression.Condition(Expression.Call(Expression.Constant(_proxy), typeof(DynamicProxy<T>).GetMethod(methodName), list), parameterExpression, dynamicMetaObject.Expression, typeof(object))), GetRestrictions().Merge(dynamicMetaObject.Restrictions));
}
private DynamicMetaObject CallMethodNoResult(string methodName, DynamicMetaObjectBinder binder, Expression[] args, [System.Runtime.CompilerServices.Nullable(new byte[] {
1,
0
})] Fallback fallback)
{
DynamicMetaObject dynamicMetaObject = fallback(null);
IList<Expression> list = new List<Expression>();
list.Add(Expression.Convert(base.Expression, typeof(T)));
list.Add(Constant(binder));
CollectionUtils.AddRange<Expression>(list, (IEnumerable<Expression>)args);
return new DynamicMetaObject(Expression.Condition(Expression.Call(Expression.Constant(_proxy), typeof(DynamicProxy<T>).GetMethod(methodName), list), Expression.Empty(), dynamicMetaObject.Expression, typeof(void)), GetRestrictions().Merge(dynamicMetaObject.Restrictions));
}
private BindingRestrictions GetRestrictions()
{
if (base.Value != null || !base.HasValue)
return BindingRestrictions.GetTypeRestriction(base.Expression, base.LimitType);
return BindingRestrictions.GetInstanceRestriction(base.Expression, null);
}
public override IEnumerable<string> GetDynamicMemberNames()
{
return _proxy.GetDynamicMemberNames((T)base.Value);
}
}
}