dotnet-testing-nsubstitute-mocking

To mock dependencies in C# unit tests using NSubstitute, use Substitute.For to create test doubles and Returns to define outputs. This isolates dependencies for reliable testing in .NET projects.

In .NET dependency substitution, a stub provides predefined return values using Returns, while a mock verifies interactions using Received. This Skill covers both patterns for isolating dependencies.

Yes, you can verify method calls and argument matching with NSubstitute in xUnit by using the Received method with argument matchers to validate interactions and capture arguments in C# tests.

To simulate exceptions for asynchronous flows in C# unit tests, use the Throws method with NSubstitute. This allows testing error handling and failure scenarios in dependency substitution.

Yes, this NSubstitute guidance works with dependency injection and logging patterns commonly used in .NET projects. It provides real-world testing scenarios for DI and asynchronous flows.

Use NSubstitute for .NET unit testing when you need clear syntax for substituting dependencies, setting return values, and verifying calls. It handles complex argument matching and exception simulation effectively.