When using XUnit tests in Visual Studio after upgrading my Entity Framework version from 8 to 9 (EF8 to EF9), I started receiving the following error when trying to run my API tests:
System.InvalidOperationException
HResult=0x80131509
Message=Services for database providers 'Microsoft.EntityFrameworkCore.SqlServer', 'Microsoft.EntityFrameworkCore.InMemory' have been registered in the service provider. Only a single database provider can be registered in a service provider. If possible, ensure that Entity Framework is managing its service provider by removing the call to 'UseInternalServiceProvider'. Otherwise, consider conditionally registering the database provider, or maintaining one service provider per database provider.
Source=Microsoft.EntityFrameworkCore
StackTrace:
at Microsoft.EntityFrameworkCore.Internal.DbContextServices.Initialize(IServiceProvider scopedProvider, DbContextOptions contextOptions, DbContext context)
at Microsoft.EntityFrameworkCore.DbContext.get_ContextServices()
at Microsoft.EntityFrameworkCore.DbContext.get_InternalServiceProvider()
at Microsoft.EntityFrameworkCore.DbContext.Microsoft.EntityFrameworkCore.Infrastructure.IInfrastructure<System.IServiceProvider>.get_Instance()
at Microsoft.EntityFrameworkCore.Infrastructure.Internal.InfrastructureExtensions.GetService(IInfrastructure`1 accessor, Type serviceType)
at Microsoft.EntityFrameworkCore.Infrastructure.Internal.InfrastructureExtensions.GetService[TService](IInfrastructure`1 accessor)
at Microsoft.EntityFrameworkCore.Infrastructure.AccessorExtensions.GetService[TService](IInfrastructure`1 accessor)
at Microsoft.EntityFrameworkCore.Infrastructure.DatabaseFacade.get_Dependencies()
at Microsoft.EntityFrameworkCore.Infrastructure.DatabaseFacade.EnsureCreated()
at YTG.RVS.RVAdvert.X.API.Tests.CustomWebApplicationFactory`1.<>c.<ConfigureWebHost>b__0_0(IServiceCollection services) in C:\SourceYTGI\YTG-RVS-RVAdvert-API-PROC\Source\YTG.RVS.RVAdvert.X.API.Tests\CustomWebApplicationFactory.cs:line 78
at Microsoft.Extensions.Hosting.HostBuilder.InitializeServiceProvider()
at Microsoft.Extensions.Hosting.HostBuilder.Build()
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.CreateHost(IHostBuilder builder)
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.ConfigureHostBuilder(IHostBuilder hostBuilder)
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.EnsureServer()
at Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory`1.get_Services()
at YTG.RVS.RVAdvert.X.API.Tests.AdvertTests.get_RVSalesRep() in C:\SourceYTGI\YTG-RVS-RVAdvert-API-PROC\Source\YTG.RVS.RVAdvert.X.API.Tests\AdvertTests.cs:line 63
at YTG.RVS.RVAdvert.X.API.Tests.AdvertTests.<GETAdvertByUniqueIdTest01>d__8.MoveNext() in C:\SourceYTGI\YTG-RVS-RVAdvert-API-PROC\Source\YTG.RVS.RVAdvert.X.API.Tests\AdvertTests.cs:line 91
at Xunit.Sdk.TestInvoker`1.<>c__DisplayClass47_0.<<InvokeTestMethodAsync>b__1>d.MoveNext()
at Xunit.Sdk.ExecutionTimer.<AggregateAsync>d__4.MoveNext()
at Xunit.Sdk.ExceptionAggregator.<RunAsync>d__9.MoveNext()
This occurs in the CustomWebApplicationFactory class at the line:
db.Database.EnsureCreated();
In your ConfigureWebHost class, there is a line where you remove your stock DBContext and add an in-memory version. That line likely looks like this:
ServiceDescriptor descriptor1 = services.SingleOrDefault(
d => d.ServiceType == typeof(DbContextOptions<RVSAccountsContext>))!;
It turns out an undocumented breaking change in the EF9 implementation is causing this. DbContextOptions should no longer be used here. If you change this line to the new implementation, it should resolve your issue:
ServiceDescriptor descriptor1 = services.SingleOrDefault(
d => d.ServiceType == typeof(IDbContextOptionsConfiguration<RVSAccountsContext>))!;
This issue is documented here:
https://github.com/dotnet/efcore/issues/35126#issuecomment-2576387727
