Expression.Property() throws System.ArgumentException: 'The method 'X' is not a property accessor (Parameter 'propertyAccessor')'

[voroninp]

Description

Method public static MemberExpression Property(Expression? expression, MethodInfo propertyAccessor) throws System.ArgumentException: 'The method 'X' is not a property accessor (Parameter 'propertyAccessor')' for getters reflected via descendant class.

Internally this method looks for the property having same getter as passed method:

[RequiresUnreferencedCode(PropertyFromAccessorRequiresUnreferencedCode)]
public static MemberExpression Property(Expression? expression, MethodInfo propertyAccessor)
{
    ArgumentNullException.ThrowIfNull(propertyAccessor);
    ValidateMethodInfo(propertyAccessor, nameof(propertyAccessor));
    return Property(expression, GetProperty(propertyAccessor, nameof(propertyAccessor)));
}

[RequiresUnreferencedCode(PropertyFromAccessorRequiresUnreferencedCode)]
private static PropertyInfo GetProperty(MethodInfo mi, string? paramName, int index = -1)
{
    Type? type = mi.DeclaringType;
    if (type != null)
    {
        BindingFlags flags = BindingFlags.Public | BindingFlags.NonPublic;
        flags |= (mi.IsStatic) ? BindingFlags.Static : BindingFlags.Instance;
        PropertyInfo[] props = type.GetProperties(flags);
        foreach (PropertyInfo pi in props)
        {
            if (pi.CanRead && CheckMethod(mi, pi.GetGetMethod(nonPublic: true)!))
            {
                return pi;
            }
            if (pi.CanWrite && CheckMethod(mi, pi.GetSetMethod(nonPublic: true)!))
            {
                return pi;
            }
        }
    }

    throw Error.MethodNotPropertyAccessor(mi.DeclaringType, mi.Name, paramName, index);
}

[UnconditionalSuppressMessage("ReflectionAnalysis", "IL2075:UnrecognizedReflectionPattern",
    Justification = "Since the methods are already supplied, they won't be trimmed. Just checking for method equality.")]
private static bool CheckMethod(MethodInfo method, MethodInfo propertyMethod)
{
    // WARNING, ALERT, DANGER: These won't equal if getter was acquired via descendant type!!!
    if (method.Equals(propertyMethod))
    {
        return true;
    }
    // If the type is an interface then the handle for the method got by the compiler will not be the
    // same as that returned by reflection.
    // Check for this condition and try and get the method from reflection.
    Type type = method.DeclaringType!;
    if (type.IsInterface && method.Name == propertyMethod.Name && type.GetMethod(method.Name) == propertyMethod)
    {
        return true;
    }
    return false;
}

The only problem is that getters reflected via ancestor and descendant differ! Type? type =mi.DeclaringType; is the core thing.

It should be Type? type = mi.ReflectedType;

Reproduction Steps

See this repo to reproduce.

Method public static MemberExpression Property(Expression? expression, MethodInfo propertyAccessor)

Expected behavior

It should just work.

Actual behavior

If fails.

Regression?

I have no clue.

Known Workarounds

If I use an overload version:

public static MemberExpression Property(Expression? expression, PropertyInfo property)

it works ok. And it's obviously faster because there's no search for the property. But anyway...

Configuration

No response

Other information

No response

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