PosInfoMoq2001.md

PosInfoMoq2001: The Setup()/SetupSet() method must be used only on overridable members

Property	Value
Rule ID	PosInfoMoq2001
Title	The Setup()/SetupSet() method must be used only on overridable members
Category	Compilation
Default severity	Error

Cause

The Setup() or SetupSet() methods must be applied only for overridable members. An overridable member is a method or property which is in:

• An interface.
• A non-sealed class. In this case, the member must be:
  • Defines as abstract.
  • Or defined as virtual

Rule description

The Setup() method must be applied only for overridable members.

For example:

• The following methods and properties can be mock and used in the Setup() method:
  • IService.MethodCanBeMocked()
  • IService.PropertyCanBeMocked
  • Service.VirtualMethodCanBeMocked
  • Service.VirtualPropertyCanBeMocked
  • Service.AbstractMethodCanBeMocked
  • Service.AbstractPropertyCanBeMocked
• The following properties can be mock and used in the SetupSet() method:
  • IService.PropertyCanBeMocked
  • Service.VirtualPropertyCanBeMocked
  • Service.AbstractPropertyCanBeMocked

public interface IService
{
	void MethodCanBeMocked();

	string PropertyCanBeMocked { get; set; }
}

public abstract class Service
{
	public virtual void VirtualMethodCanBeMocked() { ... }

	public virtual void VirtualPropertyCanBeMocked() { ... }

	public abstract void AbstractMethodCanBeMocked();

	public abstract void AbstractPropertyCanBeMocked();
}

NOTE: The extension methods can not be overriden. The C# syntax looks like a member method an interface or class, but the extension method are just simple static methods which can not be overriden.

How to fix violations

To fix a violation of this rule, be sure to mock a member in the Setup() or SetupSet() method which can be overriden.

When to suppress warnings

Do not suppress an error from this rule. If bypassed, the execution of the unit test will be failed with a MoqException thrown with the "Unsupported expression: m => m.Method(). Non-overridable members (here: Namespace.Class.Method) may not be used in setup / verification expressions." message.