Null reference exception in xunit test cases: IConfiguration settings

Question

I have written a few xUnit tests for API controller methods. I am using the configuration setting from the azure portal app settings.

This is the code I used for initializing the settings.

private readonly  IConfiguration _configuration;
public   Controller(IConfiguration configuration)
{
    _configuration = configuration;
}

In the test case class,

IConfiguration _configuration;
[Fact]
public async void Method1()
{
    Controller controller = new Controller(_configuration);


}

After run the test I am getting an error

System.NullReferenceException : Object reference not set to an instance of an object.

What is the possible solution for this?

You're passing a null to the constructor, unless you initialize `_configuration` in code you haven't posted — Panagiotis Kanavos, Mar 22 '19 at 08:40

score 1 · Answer 1 · answered Mar 22 '19 at 08:39

1

You need to define _configuration. At the moment you declare the reference, but don't assign an object to it. It is null.

You need somethine such as :

IConfiguration _configuration = new Configuration();

The above assumes, of course, that Configuration is a class that implements your IConfiguration interface.

answered Mar 22 '19 at 08:39

Mark Willis

Should a class be created that implements Iconfiguration? – D V V Mar 22 '19 at 09:08
@DVV, yes absolutely. IConfiguration is just an interface. It describes a contract, but does nothing itself. – Mark Willis Mar 22 '19 at 12:08

1 Answers1