argument constrains

Hi,

suppose that i want to check an argument against a method with a signature like

bool IsIn(param object[] list)

There are 3 ways to check the arguments of this method signiture.
First, lets remember that the CLR sees the param object[] argument as object[], so we have to check that the argument object[] fits our expectations.

Here are the different methods:

1. Use Args, TypeMock.NET will automatically validate all items of an array. So our code might look like this.

[Test]
public void testIsIn()
{
  Mock mock = MockManager.Mock(typeof(TestedClass));
  TestedClass t = new TestedClass();
  object expectedParameters = new object[] {3,"tt",false,MockManager.Any};
  mock.ExpectAndReturn("IsIn",false).Args(expectedParameters);
  Assert.AreEqual(false,t.IsIn(3,"tt",false,"SFD");
}

:idea: Tip: If you have more arguments before the params, you don't have to create the expectedParameters variable, but can use new object[]{} in the Args method.
:idea: Tip: You can pass a ParameterChecker delegate, to have your own validator. This can be done as also per array item. In this example we are using MockManager.Any which is actually an implementation of this delegate.

2. Use the ParameterChecker

public static bool CheckParams(object parameter)
{
  object[] parameters = (object[])parameter;
  bool ok = (3==(int)parameters[0]) &&
    ("tt"==(string)parameters[1]) &&
    (false==(bool)parameters[2]);
  return ok;
}
[Test]
public void testIsIn()
{
  Mock mock = MockManager.Mock(typeof(TestedClass));
  TestedClass t = new TestedClass();
  mock.ExpectAndReturn("IsIn",false).Args(new ParameterChecker(CheckParams))
  Assert.AreEqual(false,t.IsIn(3,"tt",false,"SFD");
}

Here we are are checking the arguments, in the ParameterChecker delegate


3. Use the DynamicReturnValues.

public object ParamsRetValue(object[] pars,object context) 
{
  // first parameter is an object array
  object[] parameters = (object[])pars[0];
  Assert.AreEqual(3,(int)parameters[0]);
  Assert.AreEqual("tt",(string)parameters[1]);
  Assert.AreEqual(false,(bool)parameters[2]);
  return false;
}
[Test]
public void testIsIn()
{
  Mock mock = MockManager.Mock(typeof(TestedClass));
  TestedClass t = new TestedClass();
  mock.ExpectAndReturn("IsIn",new DynamicReturnValue(ParamsRetValue));
  Assert.AreEqual(false,t.IsIn(3,"tt",false,"SFD");
}

Here we are are checking the arguments, in the DynamicReturnValue delegate

other libraries have build in a number of argument constrains do u have such support

This is true, but instead of creating different constraints that developers will have to learn, we created a flexible interface that any checker can be implemented. We distribute TypeMock with one checker, the MockManager,Any. Of course if you would like to see more checkers please post a request. We will take your ideas seriously.

by the way the type mock looks/works beautifull

Thanks alot.

Just as a reminder, when using the DynamicReturnValues, you can continue with the normal execution of the method by returning MockManager.CONTINUE_WITH_METHOD (This is called verify mode)

public object ParamsRetValue(object[] pars,object context) 
{
  // first parameter is an object array
  object[] parameters = (object[])pars[0];
  Assert.AreEqual(3,(int)parameters[0]);
  Assert.AreEqual("tt",(string)parameters[1]);
  Assert.AreEqual(false,(bool)parameters[2]);
  return MockManager.CONTINUE_WITH_METHOD;
}

The above code will check the arguments and if they are ok, the original method will be run.

Hi,
This feature has been added in version 2.1