dotnet ef migrations fails with "...doesn't reference Microsoft.EntityFrameworkCore.Design ..." but design package is added

[cerkoid]

Question

We are having problems with ef tools.

Your startup project 'ENS3.Migrations' doesn't reference Microsoft.EntityFrameworkCore.Design. This package is required for the Entity Framework Core Tools to work. Ensure your startup project is correct, install the package, and try again.

But Microsoft.EntityFrameworkCore.Design is referenced and package manager restores the package. What could be wrong, how to diagnose the problem?

Your code

Part of ENS3.Migrations.csproj file that is added using package manager
<ItemGroup>
  <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="9.0.0">
    <PrivateAssets>all</PrivateAssets>
    <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
  </PackageReference>
</ItemGroup>

Stack traces

Verbose output

EF Core version

9.0.0

Database provider

No response

Target framework

.NET 9.0

Operating system

Windows 11

IDE

Microsoft Visual Studio Community 2022 (64-bit) - Preview Version 17.13.0 Preview 3.0

[aldrashan]

You need to build the project once after adding the package, otherwise you get that error.

[geertdoornbos]

You need to build the project once after adding the package, otherwise you get that error.

Sorry, doesn't help.

    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="9.0.1">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="9.0.1" />

dotnet build 

Successful

dotnet ef migrations add MigrationX

Failed - "Your startup project 'Prj.EntityFramework.SqlServer' doesn't reference Microsoft.EntityFrameworkCore.Design. This package is required for the Entity Framework Core Tools to work. Ensure your startup project is correct, install the package, and try again."

dotnet ef

Entity Framework Core .NET Command-line Tools 9.0.1

[adamburgess]

Can I also pipe in here and say this happened to me today. I'm not sure exactly when it started to happen, but it was working fine a week or two ago, and I don't think I've changed anything apart from keeping VS 2022 preview up to date.

Removing the PrivateAssets did fix it – but this isn't a solution as I don't want the design dlls to be in the published output.

I am also using the scaffold command, not migrations.

[aldrashan]

Strange, it's working in my console program.

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net9.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="9.*">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="9.*" />
  </ItemGroup>
</Project>

I'm using VS Enterprise 2022 version 17.12.4 though, not a preview version.

PM> dotnet ef dbcontext scaffold "..." Microsoft.EntityFrameworkCore.SqlServer -o MSSQL/Db -c OurDbContext -f --no-onconfiguring --no-pluralize
Build started...
Build succeeded.
PM> 

[roji]

This is something that generally works - I can't repro this, and almost all EF users use dotnet ef migrations successfully. I'm not saying there isn't a problem here, but we're going to need precise repro steps in order to investigate here.

[cerkoid]

I don't know... I have 2 different projects on two computers, both running windows 11 with Microsoft Visual Studio Community 2022 (64-bit) - Preview Version 17.13.0 Preview 3.0. EF core tools upgraded to latest version, migration fails. I understand that most users don't have problems. We are using ef core for years, but this problem occured this week on both computers and I have no idea what changed, because source code did not...

Sample project that does not work on my current setup:
EFCoreTest.zip

cmd: dotnet ef migrations add Initial --context TestDbContext -o Migrations/PostgreSQL/Test

outputs:

Build started...
Build succeeded.
Your startup project 'EFCoreTest' doesn't reference Microsoft.EntityFrameworkCore.Design. This package is required for the Entity Framework Core Tools to work. Ensure your startup project is correct, install the package, and try again.

[thoemmi]

I experienced the same issue since Preview 3 of Visual Studio (.NET SDK 9.0.200-preview.0.25057.12)
My workaround was to add a global.json to pin the latest stable SDK:

dotnet new globaljson --sdk-version 9.0.102

[cincuranet]

Using your repro, I'm not able to reproduce it. No error and migration is created.

Using:

.NET SDK:
 Version:           9.0.102
 Commit:            cb83cd4923
 Workload version:  9.0.100-manifests.4a54b1a6
 MSBuild version:   17.12.18+ed8c6aec5

Host:
  Version:      9.0.1
  Architecture: x64
  Commit:       c8acea2262

Unless we get repro, there's not much we can do.

[thoemmi]

The error does not occur with the 9.0.102 but the current preview, as several comments stated above.

I'm using:

.NET SDK:
 Version:           9.0.200-preview.0.25057.12
 Commit:            cf6faae8d1
 Workload version:  9.0.200-manifests.693890c1
 MSBuild version:   17.13.0-preview-24569-04+8f6b

Host:
  Version:      9.0.1
  Architecture: x64
  Commit:       c8acea2262

[cincuranet]

@AndriySvyryd are we interested, given it is happening on preview version?

[thoemmi]

Well, IMHO preview versions are released so everyone can check that the next official release won't break your stuff. So this issue can be seen as a hint that EF migrations might break with the next minor release of .NET SDK.

[AndriySvyryd]

This is a duplicate of #35265, it will be fixed in EF 10.

As a workaround add <Publish>true</Publish>. It will still be added to the output folder, but it won't be referenced, so you can just delete it:

    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="9.0.1">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      <Publish>true</Publish>
    </PackageReference>

[AndriySvyryd]

Added this to breaking changes.