netcore/System.Private.CoreLib/shared/System/Reflection/MemberInfo.cs

   1 // Licensed to the .NET Foundation under one or more agreements.
   2 // The .NET Foundation licenses this file to you under the MIT license.
   3 // See the LICENSE file in the project root for more information.
   4
   5 using System.Collections.Generic;
   6 using System.Runtime.CompilerServices;
   7
   8 namespace System.Reflection
   9 {
  10     public abstract partial class MemberInfo : ICustomAttributeProvider
  11     {
  12         protected MemberInfo() { }
  13
  14         public abstract MemberTypes MemberType { get; }
  15         public abstract string Name { get; }
  16         public abstract Type? DeclaringType { get; }
  17         public abstract Type? ReflectedType { get; }
  18
  19         public virtual Module Module
  20         {
  21             get
  22             {
  23                 // This check is necessary because for some reason, Type adds a new "Module" property that hides the inherited one instead
  24                 // of overriding.
  25
  26                 if (this is Type type)
  27                     return type.Module;
  28
  29                 throw NotImplemented.ByDesign;
  30             }
  31         }
  32
  33         public virtual bool HasSameMetadataDefinitionAs(MemberInfo other) { throw NotImplemented.ByDesign; }
  34
  35         public abstract bool IsDefined(Type attributeType, bool inherit);
  36         public abstract object[] GetCustomAttributes(bool inherit);
  37         public abstract object[] GetCustomAttributes(Type attributeType, bool inherit);
  38
  39         public virtual IEnumerable<CustomAttributeData> CustomAttributes => GetCustomAttributesData();
  40         public virtual IList<CustomAttributeData> GetCustomAttributesData() { throw NotImplemented.ByDesign; }
  41         public virtual bool IsCollectible => true;
  42         public virtual int MetadataToken => throw new InvalidOperationException();
  43
  44         public override bool Equals(object? obj) => base.Equals(obj);
  45         public override int GetHashCode() => base.GetHashCode();
  46
  47         [MethodImpl(MethodImplOptions.AggressiveInlining)]
  48         public static bool operator ==(MemberInfo? left, MemberInfo? right)
  49         {
  50             // Test "right" first to allow branch elimination when inlined for null checks (== null)
  51             // so it can become a simple test
  52             if (right is null)
  53             {
  54                 // return true/false not the test result https://github.com/dotnet/coreclr/issues/914
  55                 return (left is null) ? true : false;
  56             }
  57
  58             // Try fast reference equality and opposite null check prior to calling the slower virtual Equals
  59             if ((object?)left == (object)right)
  60             {
  61                 return true;
  62             }
  63
  64             return (left is null) ? false : left.Equals(right);
  65         }
  66
  67         public static bool operator !=(MemberInfo? left, MemberInfo? right) => !(left == right);
  68     }
  69 }