How can we debug with InMemoryDatabase and how can we know exactly the key is duplicate?

Kha Vo 0

How can we debug with InMemoryDatabase Unit test?

Also I have question that when I get this error for example "An item with the same key has already been added. Key: 16c568e8-b00d-46b2-ab27-cdb7685839ae" why VS don't point exactly what entity is duplicate key? I can't also in Callstack

Or another example that when we get error "Null Reference Objection. Object reference not set to an instance of an object" I don't see what exactly object is null.

Should we have the new update for VS of this point? It will help developer saving time and more convenience while working.

Thanks.

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Ping Ni-MSFT 2,240 Reputation points Microsoft Vendor

2024-04-11T06:44:26.63+00:00

Hi @Kha Vo, it is better for you to share enough code which can reproduce the issue.
Kha Vo 0 Reputation points

2024-04-11T07:48:05.2966667+00:00

Hi @Ping Ni-MSFT I am working upgrade from .NET Core 3.1 to .NET 6 and working on Unit test using InMemoryDatabase. And I have the initial seeding data for my all test case.

I will get error "An item with the same key has already been added. Key: xxx-xxx". But I see the issue not happen from NewGuid() because this key can't duplicate. So that I need to know what is the entity is duplicate key? And I see that I can't see exactly entity is get duplicate key also in call stack.
From my side I think Visual Studio need to point or show what is entity causing error will be better. Or my another example about the error "Null Reference Objection. Object reference not set to an instance of an object". It will be valuable feature for developer.
Ping Ni-MSFT 2,240 Reputation points Microsoft Vendor

2024-04-11T09:20:24.3166667+00:00

Hi @Kha Vo, I am so sorry that visual studio cannot achieve such requirement from now on.
AgaveJoe 26,136 Reputation points

2024-04-11T10:16:47.4033333+00:00

So that I need to know what is the entity is duplicate key?

The error message tells you a key field is duplicated. The only entity that is being saved in the screenshot is the FieldTranslations entity. Basically, your logic is trying to do an INSERT when it should be doing an UPDATE. You should check if the Primary Key exists before blindly committing an update.

Or my another example about the error "Null Reference Objection. Object reference not set to an instance of an object".

The null reference exception means the code tries to access a member of an object that has not been created. In my opinion the null reference exception is one of the easiest exceptions to debug because the error message shows the line of code and usually the name of the object that is null. All you have to do is figure out why the object is null. Then add code to check for null before accessing members of the object.