Fix to #33004 - Unfulfillable nullable contraints are set for complex types with TPH entities

src/EFCore.Relational/Extensions/RelationalPropertyExtensions.cs

@@ -1188,7 +1188,7 @@ public static bool IsColumnNullable(this IReadOnlyProperty property, in StoreObj
         }
 
         return property.IsNullable
-            || (property.DeclaringType is IReadOnlyEntityType entityType
+            || (property.DeclaringType.ContainingEntityType is IReadOnlyEntityType entityType
                 && ((entityType.BaseType != null
                         && entityType.GetMappingStrategy() == RelationalAnnotationNames.TphMappingStrategy)
                     || IsOptionalSharingDependent(entityType, storeObject, 0)));

test/EFCore.Relational.Specification.Tests/Migrations/MigrationsTestBase.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.ComponentModel.DataAnnotations;
 using Microsoft.EntityFrameworkCore.Metadata.Internal;
 using Microsoft.EntityFrameworkCore.Migrations.Internal;
 using Microsoft.EntityFrameworkCore.Scaffolding.Metadata;
@@ -2790,6 +2791,73 @@ await Test(
 """);
     }
 
+    [ConditionalFact]
+    public virtual Task Create_table_with_complex_type_with_required_properties_on_derived_entity_in_TPH()
+        => Test(
+            builder => { },
+            builder =>
+            {
+                builder.Entity(
+                    "Contact", e =>
+                    {
+                        e.Property<int>("Id").ValueGeneratedOnAdd();
+                        e.HasKey("Id");
+                        e.Property<string>("Name");
+                        e.ToTable("Contacts");
+                    });
+
+                builder.Entity(
+                    "Supplier", e =>
+                    {
+                        e.HasBaseType("Contact");
+                        e.Property<int>("Number");
+                        e.ComplexProperty<MyComplex>("MyComplex", ct =>
+                        {
+                            ct.ComplexProperty<MyNestedComplex>("MyNestedComplex").IsRequired();
+                        });
+                    });
+            },
+            model =>
+            {
+                var contactsTable = Assert.Single(model.Tables.Where(t => t.Name == "Contacts"));
+                Assert.Collection(
+                    contactsTable.Columns,
+                    c => Assert.Equal("Id", c.Name),
+                    c => Assert.Equal("Discriminator", c.Name),
+                    c => Assert.Equal("Name", c.Name),
+                    c => Assert.Equal("Number", c.Name),
+                    c =>
+                    {
+                        Assert.Equal("MyComplex_Prop", c.Name);
+                        Assert.Equal(true, c.IsNullable);
+                    },
+                    c =>
+                    {
+                        Assert.Equal("MyComplex_MyNestedComplex_Bar", c.Name);
+                        Assert.Equal(true, c.IsNullable);
+                    },
+                    c =>
+                    {
+                        Assert.Equal("MyComplex_MyNestedComplex_Foo", c.Name);
+                        Assert.Equal(true, c.IsNullable);
+                    });
+            });
+
+    protected class MyComplex
+    {
+        [Required]
+        public string Prop { get; set; }
+
+        [Required]
+        public MyNestedComplex Nested { get; set; }
+    }
+
+    public class MyNestedComplex
+    {
+        public int Foo { get; set; }
+        public DateTime Bar { get; set; }
+    }
+
     protected class Person
     {
         public int Id { get; set; }

test/EFCore.SqlServer.FunctionalTests/Migrations/MigrationsSqlServerTest.cs

@@ -11101,6 +11101,26 @@ CONSTRAINT [PK_Customers] PRIMARY KEY ([Id])
 """);
     }
 
+    [ConditionalFact]
+    public override async Task Create_table_with_complex_type_with_required_properties_on_derived_entity_in_TPH()
+    {
+        await base.Create_table_with_complex_type_with_required_properties_on_derived_entity_in_TPH();
+
+        AssertSql(
+"""
+CREATE TABLE [Contacts] (
+    [Id] int NOT NULL IDENTITY,
+    [Discriminator] nvarchar(8) NOT NULL,
+    [Name] nvarchar(max) NULL,
+    [Number] int NULL,
+    [MyComplex_Prop] nvarchar(max) NULL,
+    [MyComplex_MyNestedComplex_Bar] datetime2 NULL,
+    [MyComplex_MyNestedComplex_Foo] int NULL,
+    CONSTRAINT [PK_Contacts] PRIMARY KEY ([Id])
+);
+""");
+    }
+
     protected override string NonDefaultCollation
         => _nonDefaultCollation ??= GetDatabaseCollation() == "German_PhoneBook_CI_AS"
             ? "French_CI_AS"

test/EFCore.Sqlite.FunctionalTests/Migrations/MigrationsSqliteTest.cs

@@ -2081,6 +2081,24 @@ public override Task Rename_sequence()
     public override Task Move_sequence()
         => AssertNotSupportedAsync(base.Move_sequence, SqliteStrings.SequencesNotSupported);
 
+    public override async Task Create_table_with_complex_type_with_required_properties_on_derived_entity_in_TPH()
+    {
+        await base.Create_table_with_complex_type_with_required_properties_on_derived_entity_in_TPH();
+
+        AssertSql(
+"""
+CREATE TABLE "Contacts" (
+    "Id" INTEGER NOT NULL CONSTRAINT "PK_Contacts" PRIMARY KEY AUTOINCREMENT,
+    "Discriminator" TEXT NOT NULL,
+    "Name" TEXT NULL,
+    "Number" INTEGER NULL,
+    "MyComplex_Prop" TEXT NULL,
+    "MyComplex_MyNestedComplex_Bar" TEXT NULL,
+    "MyComplex_MyNestedComplex_Foo" INTEGER NULL
+);
+""");
+    }
+
     // SQLite does not support schemas
     protected override bool AssertSchemaNames
         => false;