How does EF Core's DbContext supress all CS8618 (non-nullable property) warnings?

Question

I know it's an issue in the past since you can search the web and SO for so many questions about getting warning from EF Core model. Today I first use EF Core for .NET 8 and I just realized the warning is not there anymore:

public class AppDbContext : DbContext
{

    public DbSet<DbAccount> Accounts { get; set; }

}

public class MyClass
{

    // The line below still receives this warning:
    // Warning CS8618 Non-nullable property 'Accounts' must contain a non-null value when exiting constructor.Consider declaring the property as nullable:
    public DbSet<DbAccount> Accounts { get; set; }

}

Interestingly it skips for members of DbContext and not DbSet type itself as you can see from the example above, my own class still receive CS8618 warning.

I have tried reading the decompiled code of DbContext and even DbSet and couldn't find anything special. How does EF Core team do that? Can I apply it to my own classes somehow (for POCO JSON classes for example)?

Ragged

For stuff I know will be set by a deserializer or similar, I just public string MyProp{get;set;} = default!; or if there are a lot of them I toggle it off with #nullable ... but I take it you're asserting to have code that doesn't do this or anything like it, nor any #nullable disable etc, but still you see no warning in the code generated by ef tools, but you do see warning in your own code? – Orangeade

@Orangeade yeah I already use null! and #nullable false currently but I am surprised EF Core could somehow did that without. The above example code I gave is from the same file, DbContext derived class doesn't get any warning but my own class gets it. That's why I am curious and want to know how to do that. – Ragged

Answer 1

Suppressing Warning CS8618 is done by EFCore.Analyzers package.

Check source code for such analyzer UninitializedDbSetDiagnosticSuppressor

Liturgist

Very interesting! Now I know where to start reading. Thanks a lot. I guess this article is a good start. – Ragged

The GitHub issue : Write a DiagnosticSuppressor for CS8618 for DbSet properties – Commie