Metadata: Add Getter/Setter support for indexed properties

Part of #13610

src/EFCore/Extensions/ConventionEntityTypeExtensions.cs

@@ -504,6 +504,28 @@ public static IConventionProperty FindDeclaredProperty([NotNull] this IConventio
             bool setTypeConfigurationSource = true, bool fromDataAnnotation = false)
             => entityType.AddProperty(name, propertyType, null, setTypeConfigurationSource, fromDataAnnotation);
 
+        /// <summary>
+        ///     Adds an indexed property to this entity type.
+        /// </summary>
+        /// <param name="entityType"> The entity type to add the property to. </param>
+        /// <param name="name"> The name of the property to add. </param>
+        /// <param name="propertyType"> The type of value the property will hold. </param>
+        /// <param name="setTypeConfigurationSource"> Indicates whether the type configuration source should be set. </param>
+        /// <param name="fromDataAnnotation"> Indicates whether the configuration was specified using a data annotation. </param>
+        /// <returns> The newly created property. </returns>
+        public static IConventionProperty AddIndexedProperty(
+            [NotNull] this IConventionEntityType entityType, [NotNull] string name, [NotNull] Type propertyType,
+            bool setTypeConfigurationSource = true, bool fromDataAnnotation = false)
+        {
+            Check.NotNull(entityType, nameof(entityType));
+
+            var indexerPropertyInfo = entityType.GetIndexerPropertyInfo();
+
+            return indexerPropertyInfo != null
+                ? entityType.AddProperty(name, propertyType, indexerPropertyInfo, setTypeConfigurationSource, fromDataAnnotation)
+                : null;
+        }
+
         /// <summary>
         ///     Gets the index defined on the given property. Returns null if no index is defined.
         /// </summary>

src/EFCore/Extensions/MutableEntityTypeExtensions.cs

@@ -6,6 +6,8 @@
 using System.Linq.Expressions;
 using System.Reflection;
 using JetBrains.Annotations;
+using Microsoft.EntityFrameworkCore.Diagnostics;
+using Microsoft.EntityFrameworkCore.Infrastructure;
 using Microsoft.EntityFrameworkCore.Metadata;
 using Microsoft.EntityFrameworkCore.Metadata.Internal;
 using Microsoft.EntityFrameworkCore.Utilities;
@@ -463,6 +465,28 @@ public static IMutableProperty FindDeclaredProperty([NotNull] this IMutableEntit
             [NotNull] this IMutableEntityType entityType, [NotNull] string name, [NotNull] Type propertyType)
             => entityType.AddProperty(name, propertyType, null);
 
+        /// <summary>
+        ///     Adds an indexed property to this entity type.
+        /// </summary>
+        /// <param name="entityType"> The entity type to add the property to. </param>
+        /// <param name="name"> The name of the property to add. </param>
+        /// <param name="propertyType"> The type of value the property will hold. </param>
+        /// <returns> The newly created property. </returns>
+        public static IMutableProperty AddIndexedProperty(
+            [NotNull] this IMutableEntityType entityType, [NotNull] string name, [NotNull] Type propertyType)
+        {
+            Check.NotNull(entityType, nameof(entityType));
+
+            var indexerPropertyInfo = entityType.GetIndexerPropertyInfo();
+            if (indexerPropertyInfo == null)
+            {
+                throw new InvalidOperationException(
+                    CoreStrings.NonIndexerEntityType(name, entityType.DisplayName(), typeof(string).ShortDisplayName()));
+            }
+
+            return entityType.AddProperty(name, propertyType, indexerPropertyInfo);
+        }
+
         /// <summary>
         ///     Gets the index defined on the given property. Returns null if no index is defined.
         /// </summary>

src/EFCore/Extensions/PropertyBaseExtensions.cs

@@ -82,6 +82,18 @@ public static string GetFieldName([NotNull] this IPropertyBase propertyBase)
         public static bool IsShadowProperty([NotNull] this IPropertyBase property)
             => Check.NotNull(property, nameof(property)).GetIdentifyingMemberInfo() == null;
 
+        /// <summary>
+        ///     Gets a value indicating whether this is an indexer property. An indexer property is one that is accessed through
+        ///     indexer on entity class.
+        /// </summary>
+        /// <param name="property"> The property to check. </param>
+        /// <returns>
+        ///     <c>True</c> if the property is an indexer property, otherwise <c>false</c>.
+        /// </returns>
+        public static bool IsIndexerProperty([NotNull] this IPropertyBase property)
+            => Check.NotNull(property, nameof(property)).GetIdentifyingMemberInfo() is PropertyInfo propertyInfo
+                && propertyInfo.IsIndexerProperty();
+
         /// <summary>
         ///     <para>
         ///         Gets the <see cref="PropertyAccessMode" /> being used for this property.

src/EFCore/Infrastructure/ModelValidator.cs

@@ -783,7 +783,7 @@ private bool Contains(IForeignKey inheritedFk, IForeignKey derivedFk)
                         .GetDeclaredProperties()
                         .Cast<IPropertyBase>()
                         .Concat(entityType.GetDeclaredNavigations())
-                        .Where(p => !p.IsShadowProperty()));
+                        .Where(p => !p.IsShadowProperty() && !p.IsIndexerProperty()));
 
                 var constructorBinding = (InstantiationBinding)entityType[CoreAnnotationNames.ConstructorBinding];
 

src/EFCore/Metadata/Internal/ClrPropertyGetterFactory.cs

@@ -40,7 +40,7 @@ public override IClrPropertyGetter Create(IPropertyBase property)
             Expression readExpression;
             if (memberInfo.DeclaringType.IsAssignableFrom(typeof(TEntity)))
             {
-                readExpression = Expression.MakeMemberAccess(entityParameter, memberInfo);
+                readExpression = CreateMemberAccess(entityParameter);
             }
             else
             {
@@ -57,7 +57,7 @@ public override IClrPropertyGetter Create(IPropertyBase property)
                         Expression.Condition(
                             Expression.ReferenceEqual(converted, Expression.Constant(null)),
                             Expression.Default(memberInfo.GetMemberType()),
-                            Expression.MakeMemberAccess(converted, memberInfo))
+                            CreateMemberAccess(converted))
                     });
             }
 
@@ -101,6 +101,14 @@ public override IClrPropertyGetter Create(IPropertyBase property)
             return new ClrPropertyGetter<TEntity, TValue>(
                 Expression.Lambda<Func<TEntity, TValue>>(readExpression, entityParameter).Compile(),
                 Expression.Lambda<Func<TEntity, bool>>(hasDefaultValueExpression, entityParameter).Compile());
+
+            Expression CreateMemberAccess(Expression parameter)
+            {
+                return propertyBase?.IsIndexerProperty() == true
+                    ? Expression.MakeIndex(
+                        entityParameter, (PropertyInfo)memberInfo, new List<Expression>() { Expression.Constant(propertyBase.Name) })
+                    : (Expression)Expression.MakeMemberAccess(parameter, memberInfo);
+            }
         }
     }
 }

src/EFCore/Metadata/Internal/ClrPropertySetterFactory.cs

@@ -45,8 +45,7 @@ public override IClrPropertySetter Create(IPropertyBase property)
             Expression writeExpression;
             if (memberInfo.DeclaringType.IsAssignableFrom(typeof(TEntity)))
             {
-                writeExpression = Expression.MakeMemberAccess(entityParameter, memberInfo)
-                    .Assign(convertedParameter);
+                writeExpression = CreateMemberAssignment(entityParameter);
             }
             else
             {
@@ -62,8 +61,7 @@ public override IClrPropertySetter Create(IPropertyBase property)
                             Expression.TypeAs(entityParameter, memberInfo.DeclaringType)),
                         Expression.IfThen(
                             Expression.ReferenceNotEqual(converted, Expression.Constant(null)),
-                            Expression.MakeMemberAccess(converted, memberInfo)
-                                .Assign(convertedParameter))
+                            CreateMemberAssignment(converted))
                     });
             }
 
@@ -78,6 +76,16 @@ public override IClrPropertySetter Create(IPropertyBase property)
                 && propertyType.UnwrapNullableType().IsEnum
                     ? new NullableEnumClrPropertySetter<TEntity, TValue, TNonNullableEnumValue>(setter)
                     : (IClrPropertySetter)new ClrPropertySetter<TEntity, TValue>(setter);
+
+            Expression CreateMemberAssignment(Expression parameter)
+            {
+                return propertyBase?.IsIndexerProperty() == true
+                    ? Expression.Assign(
+                        Expression.MakeIndex(
+                            entityParameter, (PropertyInfo)memberInfo, new List<Expression>() { Expression.Constant(propertyBase.Name) }),
+                        convertedParameter)
+                    : Expression.MakeMemberAccess(parameter, memberInfo).Assign(convertedParameter);
+            }
         }
     }
 }

src/EFCore/Metadata/Internal/EntityType.cs

@@ -1599,7 +1599,7 @@ private Type ValidateClrMember(string name, MemberInfo memberInfo, bool throwOnN
 
             if (name != memberInfo.GetSimpleMemberName())
             {
-                if ((memberInfo as PropertyInfo)?.IsEFIndexerProperty() != true)
+                if ((memberInfo as PropertyInfo)?.IsIndexerProperty() != true)
                 {
                     if (throwOnNameMismatch)
                     {
@@ -2066,7 +2066,7 @@ public virtual Index RemoveIndex([NotNull] Index index)
 
             if (memberInfo != null
                 && propertyType != memberInfo.GetMemberType()
-                && (memberInfo as PropertyInfo)?.IsEFIndexerProperty() != true)
+                && (memberInfo as PropertyInfo)?.IsIndexerProperty() != true)
             {
                 if (typeConfigurationSource != null)
                 {

src/EFCore/Metadata/Internal/InternalEntityTypeBuilder.cs

@@ -682,7 +682,7 @@ public virtual bool CanAddProperty([NotNull] Type propertyType, [NotNull] string
             var memberInfo = Metadata.ClrType.GetMembersInHierarchy(name).FirstOrDefault();
             if (memberInfo != null
                 && propertyType != memberInfo.GetMemberType()
-                && (memberInfo as PropertyInfo)?.IsEFIndexerProperty() != true
+                && (memberInfo as PropertyInfo)?.IsIndexerProperty() != true
                 && typeConfigurationSource != null)
             {
                 return false;

src/EFCore/Metadata/Internal/PropertyBase.cs

@@ -80,8 +80,10 @@ public abstract class PropertyBase : ConventionAnnotatable, IMutablePropertyBase
         /// </summary>
         public virtual FieldInfo FieldInfo
         {
-            [DebuggerStepThrough] get => _fieldInfo;
-            [DebuggerStepThrough] set => SetField(value, ConfigurationSource.Explicit);
+            [DebuggerStepThrough]
+            get => _fieldInfo;
+            [DebuggerStepThrough]
+            set => SetField(value, ConfigurationSource.Explicit);
         }
 
         /// <summary>

src/EFCore/Metadata/Internal/TypeBase.cs

@@ -25,6 +25,7 @@ public abstract class TypeBase : ConventionAnnotatable, IMutableTypeBase, IConve
         private readonly Dictionary<string, ConfigurationSource> _ignoredMembers
             = new Dictionary<string, ConfigurationSource>(StringComparer.Ordinal);
 
+        private PropertyInfo _indexerPropertyInfo;
         private Dictionary<string, PropertyInfo> _runtimeProperties;
         private Dictionary<string, FieldInfo> _runtimeFields;
 
@@ -168,6 +169,29 @@ public virtual void UpdateConfigurationSource(ConfigurationSource configurationS
             return _runtimeFields;
         }
 
+        /// <summary>
+        ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
+        ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
+        ///     any release. You should only use it directly in your code with extreme caution and knowing that
+        ///     doing so can result in application failures when updating to a new Entity Framework Core release.
+        /// </summary>
+        public virtual PropertyInfo GetIndexerPropertyInfo()
+        {
+            if (ClrType == null)
+            {
+                return null;
+            }
+
+            if (_indexerPropertyInfo == null)
+            {
+                var indexerPropertyInfo = GetRuntimeProperties().Values.FirstOrDefault(pi => pi.IsIndexerProperty());
+
+                Interlocked.CompareExchange(ref _indexerPropertyInfo, indexerPropertyInfo, null);
+            }
+
+            return _indexerPropertyInfo;
+        }
+
         /// <summary>
         ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
         ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
@@ -198,6 +222,7 @@ public virtual void ClearCaches()
         {
             _runtimeProperties = null;
             _runtimeFields = null;
+            _indexerPropertyInfo = null;
             Thread.MemoryBarrier();
         }
 

src/EFCore/Metadata/Internal/TypeBaseExtensions.cs

@@ -45,6 +45,15 @@ public static bool HasClrType([NotNull] this ITypeBase type)
         public static IReadOnlyDictionary<string, FieldInfo> GetRuntimeFields([NotNull] this ITypeBase type)
             => (type as TypeBase).GetRuntimeFields();
 
+        /// <summary>
+        ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
+        ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
+        ///     any release. You should only use it directly in your code with extreme caution and knowing that
+        ///     doing so can result in application failures when updating to a new Entity Framework Core release.
+        /// </summary>
+        public static PropertyInfo GetIndexerPropertyInfo([NotNull] this ITypeBase type)
+            => (type as TypeBase).GetIndexerPropertyInfo();
+
         /// <summary>
         ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
         ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
@@ -53,17 +62,9 @@ public static bool HasClrType([NotNull] this ITypeBase type)
         /// </summary>
         public static MemberInfo FindClrMember([NotNull] this TypeBase type, [NotNull] string name)
         {
-            if (type.GetRuntimeProperties().TryGetValue(name, out var property))
-            {
-                return property;
-            }
-
-            if (type.GetRuntimeFields().TryGetValue(name, out var field))
-            {
-                return field;
-            }
-
-            return null;
+            return type.GetRuntimeProperties().TryGetValue(name, out var property)
+                ? property
+                : (MemberInfo)(type.GetRuntimeFields().TryGetValue(name, out var field) ? field : null);
         }
 
         /// <summary>

src/EFCore/Properties/CoreStrings.resx

@@ -1,17 +1,17 @@
 <?xml version="1.0" encoding="utf-8"?>
 <root>
-  <!--
-    Microsoft ResX Schema
-
+  <!-- 
+    Microsoft ResX Schema 
+    
     Version 2.0
-
-    The primary goals of this format is to allow a simple XML format
-    that is mostly human readable. The generation and parsing of the
-    various data types are done through the TypeConverter classes
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
     associated with the data types.
-
+    
     Example:
-
+    
     ... ado.net/XML headers & schema ...
     <resheader name="resmimetype">text/microsoft-resx</resheader>
     <resheader name="version">2.0</resheader>
@@ -26,36 +26,36 @@
         <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
         <comment>This is a comment</comment>
     </data>
-
-    There are any number of "resheader" rows that contain simple
+                
+    There are any number of "resheader" rows that contain simple 
     name/value pairs.
-
-    Each data row contains a name, and value. The row also contains a
-    type or mimetype. Type corresponds to a .NET class that support
-    text/value conversion through the TypeConverter architecture.
-    Classes that don't support this are serialized and stored with the
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
     mimetype set.
-
-    The mimetype is used for serialized objects, and tells the
-    ResXResourceReader how to depersist the object. This is currently not
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
     extensible. For a given mimetype the value must be set accordingly:
-
-    Note - application/x-microsoft.net.object.binary.base64 is the format
-    that the ResXResourceWriter will generate, however the reader can
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
     read any of the formats listed below.
-
+    
     mimetype: application/x-microsoft.net.object.binary.base64
-    value   : The object must be serialized with
+    value   : The object must be serialized with 
             : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
             : and then encoded with base64 encoding.
-
+    
     mimetype: application/x-microsoft.net.object.soap.base64
-    value   : The object must be serialized with
+    value   : The object must be serialized with 
             : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
             : and then encoded with base64 encoding.
 
     mimetype: application/x-microsoft.net.object.bytearray.base64
-    value   : The object must be serialized into a byte array
+    value   : The object must be serialized into a byte array 
             : using a System.ComponentModel.TypeConverter
             : and then encoded with base64 encoding.
     -->
@@ -1245,4 +1245,7 @@
   <data name="SkipNavigationNonCollection" xml:space="preserve">
     <value>The skip navigation '{navigation}' on entity type '{entityType}' is not a collection. Only collection skip navigation properties are currently supported.</value>
   </data>
+  <data name="NonIndexerEntityType" xml:space="preserve">
+    <value>Cannot add property '{property}' on entity type '{entity}' since there is no indexer on '{entity}' taking a single argument of type '{type}'.</value>
+  </data>
 </root>