Add GetDeclaringType to PropertyDefinition and EventDefinition. (#111646)

* Add `GetDeclaringType` to `PropertyDefinition` and `EventDefinition`.

* Add test.

* Add documentation to all `GetDeclaringType` APIs.

* Remove unnecessary code.

* Update tests.

We assert that the test assembly has types with events and properties, and acknowledge that it does not have nested types.

---------

Co-authored-by: Jan Kotas <jkotas@microsoft.com>

Author: teo-tsirpanis

src/libraries/System.Reflection.Metadata/ref/System.Reflection.Metadata.cs

@@ -715,6 +715,7 @@ public readonly partial struct EventDefinition
         public System.Reflection.Metadata.EntityHandle Type { get { throw null; } }
         public System.Reflection.Metadata.EventAccessors GetAccessors() { throw null; }
         public System.Reflection.Metadata.CustomAttributeHandleCollection GetCustomAttributes() { throw null; }
+        public System.Reflection.Metadata.TypeDefinitionHandle GetDeclaringType() { throw null; }
     }
     public readonly partial struct EventDefinitionHandle : System.IEquatable<System.Reflection.Metadata.EventDefinitionHandle>
     {
@@ -2135,6 +2136,7 @@ public readonly partial struct PropertyDefinition
         public System.Reflection.Metadata.MethodSignature<TType> DecodeSignature<TType, TGenericContext>(System.Reflection.Metadata.ISignatureTypeProvider<TType, TGenericContext> provider, TGenericContext genericContext) { throw null; }
         public System.Reflection.Metadata.PropertyAccessors GetAccessors() { throw null; }
         public System.Reflection.Metadata.CustomAttributeHandleCollection GetCustomAttributes() { throw null; }
+        public System.Reflection.Metadata.TypeDefinitionHandle GetDeclaringType() { throw null; }
         public System.Reflection.Metadata.ConstantHandle GetDefaultValue() { throw null; }
     }
     public readonly partial struct PropertyDefinitionHandle : System.IEquatable<System.Reflection.Metadata.PropertyDefinitionHandle>

src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/Internal/Tables.cs

@@ -1213,6 +1213,29 @@ internal int GetEventListStartFor(int rowId)
             int rowOffset = (rowId - 1) * this.RowSize;
             return this.Block.PeekReference(rowOffset + _EventListOffset, _IsEventRefSizeSmall);
         }
+
+        internal TypeDefinitionHandle FindTypeContainingEvent(int eventRowId, int numberOfEvents)
+        {
+            int numOfRows = this.NumberOfRows;
+            int slot = this.Block.BinarySearchForSlot(numOfRows, this.RowSize, _EventListOffset, (uint)eventRowId, _IsEventRefSizeSmall);
+            int row = slot + 1;
+            if (row == 0)
+            {
+                return default(TypeDefinitionHandle);
+            }
+
+            if (row > numOfRows)
+            {
+                if (eventRowId <= numberOfEvents)
+                {
+                    return GetParentType(numOfRows);
+                }
+
+                return default(TypeDefinitionHandle);
+            }
+
+            return GetParentType(row);
+        }
     }
 
     internal readonly struct EventPtrTableReader
@@ -1343,6 +1366,29 @@ internal int GetPropertyListStartFor(int rowId)
             int rowOffset = (rowId - 1) * this.RowSize;
             return this.Block.PeekReference(rowOffset + _PropertyListOffset, _IsPropertyRefSizeSmall);
         }
+
+        internal TypeDefinitionHandle FindTypeContainingProperty(int propertyRowId, int numberOfProperties)
+        {
+            int numOfRows = this.NumberOfRows;
+            int slot = this.Block.BinarySearchForSlot(numOfRows, this.RowSize, _PropertyListOffset, (uint)propertyRowId, _IsPropertyRefSizeSmall);
+            int row = slot + 1;
+            if (row == 0)
+            {
+                return default(TypeDefinitionHandle);
+            }
+
+            if (row > numOfRows)
+            {
+                if (propertyRowId <= numberOfProperties)
+                {
+                    return GetParentType(numOfRows);
+                }
+
+                return default(TypeDefinitionHandle);
+            }
+
+            return GetParentType(row);
+        }
     }
 
     internal readonly struct PropertyPtrTableReader

src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/MetadataReader.cs

@@ -1350,6 +1350,26 @@ internal TypeDefinitionHandle GetDeclaringType(FieldDefinitionHandle fieldDef)
             return TypeDefTable.FindTypeContainingField(fieldRowId, FieldTable.NumberOfRows);
         }
 
+        internal TypeDefinitionHandle GetDeclaringType(EventDefinitionHandle eventDef)
+        {
+            if (UseEventPtrTable)
+            {
+                eventDef = EventPtrTable.GetEventFor(eventDef.RowId);
+            }
+
+            return EventMapTable.FindTypeContainingEvent(eventDef.RowId, EventTable.NumberOfRows);
+        }
+
+        internal TypeDefinitionHandle GetDeclaringType(PropertyDefinitionHandle propertyDef)
+        {
+            if (UsePropertyPtrTable)
+            {
+                propertyDef = PropertyPtrTable.GetPropertyFor(propertyDef.RowId);
+            }
+
+            return PropertyMapTable.FindTypeContainingProperty(propertyDef.RowId, PropertyTable.NumberOfRows);
+        }
+
         public string GetString(DocumentNameBlobHandle handle)
         {
             return BlobHeap.GetDocumentName(handle);

src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/TypeSystem/EventDefinition.cs

@@ -57,6 +57,14 @@ public CustomAttributeHandleCollection GetCustomAttributes()
             return new CustomAttributeHandleCollection(_reader, Handle);
         }
 
+        /// <summary>
+        /// Returns a handle to the type that declares this event.
+        /// </summary>
+        public TypeDefinitionHandle GetDeclaringType()
+        {
+            return _reader.GetDeclaringType(Handle);
+        }
+
         public EventAccessors GetAccessors()
         {
             int adder = 0;

src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/TypeSystem/FieldDefinition.cs

@@ -83,6 +83,9 @@ public TType DecodeSignature<TType, TGenericContext>(ISignatureTypeProvider<TTyp
             return decoder.DecodeFieldSignature(ref blob);
         }
 
+        /// <summary>
+        /// Returns a handle to the type that declares this field.
+        /// </summary>
         public TypeDefinitionHandle GetDeclaringType()
         {
             return _reader.GetDeclaringType(Handle);

src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/TypeSystem/MethodDefinition.cs

@@ -109,6 +109,9 @@ public MethodImplAttributes ImplAttributes
             }
         }
 
+        /// <summary>
+        /// Returns a handle to the type that declares this method.
+        /// </summary>
         public TypeDefinitionHandle GetDeclaringType()
         {
             return _reader.GetDeclaringType(Handle);

src/libraries/System.Reflection.Metadata/src/System/Reflection/Metadata/TypeSystem/PropertyDefinition.cs

@@ -69,6 +69,14 @@ public CustomAttributeHandleCollection GetCustomAttributes()
             return new CustomAttributeHandleCollection(_reader, Handle);
         }
 
+        /// <summary>
+        /// Returns a handle to the type that declares this property.
+        /// </summary>
+        public TypeDefinitionHandle GetDeclaringType()
+        {
+            return _reader.GetDeclaringType(Handle);
+        }
+
         public PropertyAccessors GetAccessors()
         {
             int getter = 0;

src/libraries/System.Reflection.Metadata/tests/Metadata/MetadataReaderTests.cs

@@ -2723,6 +2723,7 @@ public void MemberCollections_AllMembers()
                     "add_ED1",
                     "remove_ED1",
                     ".ctor",
+                    ".ctor",
                     "get_PE1",
                     "set_PE1",
                     "get_PE2",

src/libraries/System.Reflection.Metadata/tests/Metadata/TypeSystem/TypeDefinitionTests.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Reflection.Metadata.Ecma335;
 using Xunit;
 
 namespace System.Reflection.Metadata.Tests
@@ -32,5 +33,44 @@ public void ValidateTypeDefinitionIsNestedWindowsProjection()
                 Assert.Equal(typeDef.Attributes.IsNested(), typeDef.IsNested);
             }
         }
+
+        [Fact]
+        public void ValidateDeclaringType()
+        {
+            var reader = MetadataReaderTests.GetMetadataReader(Misc.Members);
+
+            Assert.NotEmpty(reader.GetTypesWithEvents());
+            Assert.NotEmpty(reader.GetTypesWithProperties());
+
+            foreach (var typeDefHandle in reader.TypeDefinitions)
+            {
+                var typeDef = reader.GetTypeDefinition(typeDefHandle);
+                foreach (var nestedTypeHandle in typeDef.GetNestedTypes())
+                {
+                    var nestedType = reader.GetTypeDefinition(nestedTypeHandle);
+                    Assert.Equal(typeDefHandle, nestedType.GetDeclaringType());
+                }
+                foreach (var fieldHandle in typeDef.GetFields())
+                {
+                    var field = reader.GetFieldDefinition(fieldHandle);
+                    Assert.Equal(typeDefHandle, field.GetDeclaringType());
+                }
+                foreach (var methodHandle in typeDef.GetMethods())
+                {
+                    var method = reader.GetMethodDefinition(methodHandle);
+                    Assert.Equal(typeDefHandle, method.GetDeclaringType());
+                }
+                foreach (var eventHandle in typeDef.GetEvents())
+                {
+                    var eventDef = reader.GetEventDefinition(eventHandle);
+                    Assert.Equal(typeDefHandle, eventDef.GetDeclaringType());
+                }
+                foreach (var propertyHandle in typeDef.GetProperties())
+                {
+                    var property = reader.GetPropertyDefinition(propertyHandle);
+                    Assert.Equal(typeDefHandle, property.GetDeclaringType());
+                }
+            }
+        }
     }
 }

src/libraries/System.Reflection.Metadata/tests/PortableExecutable/PEReaderTests.cs

@@ -245,7 +245,7 @@ private unsafe void ValidateSectionData(PEReader reader)
             {
                 0x00, 0x20, 0x00, 0x00,
                 0x0C, 0x00, 0x00, 0x00,
-                0xD0, 0x38, 0x00, 0x00
+                0x00, 0x39, 0x00, 0x00
             }, relocBlob1);
 
             AssertEx.Equal(relocBlob1, relocBlob2);

src/libraries/System.Reflection.Metadata/tests/Resources/Misc/Members.cs

@@ -21,6 +21,10 @@ public void MD1() { }
     public int PE1 { get { return 1; } set { } }
 
     event System.Action ED1;
+
+    public class N
+    {
+    }
 }
 
 public class E