MA0042: suppress diagnostic for IDbContextFactory<TContext>.CreateDbContext()

docs/Rules/MA0042.md

@@ -53,6 +53,8 @@ public sealed class Sample
 }
 ````
 
+The rule does not report a diagnostic for `IDbContextFactory<TContext>.CreateDbContext()`. The `CreateDbContextAsync()` overload was introduced only for specific edge-case scenarios where the factory itself must perform asynchronous initialization, and is not intended as a general-purpose replacement. See [dotnet/efcore#26630](https://github.com/dotnet/efcore/issues/26630) for more details.
+
 ## Additional resources
 
 - [Enforcing asynchronous code good practices using a Roslyn analyzer](https://www.meziantou.net/enforcing-asynchronous-code-good-practices-using-a-roslyn-analyzer.htm)

src/Meziantou.Analyzer/Rules/DoNotUseBlockingCallInAsyncContextAnalyzer.cs

@@ -95,6 +95,7 @@ public Context(Compilation compilation)
 
             DbContextSymbol = compilation.GetBestTypeByMetadataName("Microsoft.EntityFrameworkCore.DbContext");
             DbSetSymbol = compilation.GetBestTypeByMetadataName("Microsoft.EntityFrameworkCore.DbSet`1");
+            DbContextFactorySymbol = compilation.GetBestTypeByMetadataName("Microsoft.EntityFrameworkCore.IDbContextFactory`1");
 
             ServiceProviderServiceExtensionsSymbol = compilation.GetBestTypeByMetadataName("Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions");
             if (ServiceProviderServiceExtensionsSymbol is not null)
@@ -146,6 +147,7 @@ public Context(Compilation compilation)
 
         private INamedTypeSymbol? DbContextSymbol { get; }
         private INamedTypeSymbol? DbSetSymbol { get; }
+        private INamedTypeSymbol? DbContextFactorySymbol { get; }
 
         public INamedTypeSymbol? Moq_MockSymbol { get; }
 
@@ -248,6 +250,15 @@ private bool HasAsyncEquivalent(IInvocationOperation operation, [NotNullWhen(tru
                 return false;
             }
 
+            // IDbContextFactory<TContext>.CreateDbContext() - CreateDbContextAsync() is only for specific edge-cases
+            // https://github.com/dotnet/efcore/issues/26630
+            else if (DbContextFactorySymbol is not null && targetMethod.Name is "CreateDbContext" &&
+                     (targetMethod.ContainingType.OriginalDefinition.IsEqualTo(DbContextFactorySymbol) ||
+                      targetMethod.ContainingType.ImplementsGenericInterface(DbContextFactorySymbol)))
+            {
+                return false;
+            }
+
             else if (Moq_MockSymbol is not null && targetMethod.Name is "Raise" && targetMethod.ContainingType.OriginalDefinition.IsEqualTo(Moq_MockSymbol))
             {
                 return false;

tests/Meziantou.Analyzer.Test/Rules/DoNotUseBlockingCallInAsyncContextAnalyzer_AsyncContextTests.cs

@@ -1926,6 +1926,33 @@ async Task A()
               .ValidateAsync();
     }
 
+    [Fact]
+    [Trait("Issue", "https://github.com/meziantou/Meziantou.Analyzer/issues/891")]
+    public async Task IDbContextFactory_CreateDbContext_NoReport()
+    {
+        await CreateProjectBuilder()
+              .WithTargetFramework(TargetFramework.Net6_0)
+              .AddNuGetReference("Microsoft.EntityFrameworkCore", "6.0.8", "lib/net6.0/")
+              .AddNuGetReference("Microsoft.EntityFrameworkCore.Abstractions", "6.0.8", "lib/net6.0/")
+              .WithSourceCode("""
+                using System.Threading.Tasks;
+                using Microsoft.EntityFrameworkCore;
+
+                class BloggingContext : DbContext { }
+
+                class Sample
+                {
+                    private IDbContextFactory<BloggingContext> _factory;
+
+                    async Task A()
+                    {
+                        await using var context = _factory.CreateDbContext();
+                    }
+                }
+                """)
+              .ValidateAsync();
+    }
+
     [Fact]
     public async Task IAsyncEnumerable()
     {