Help with the Moles syntax for testing private method with generics - moles

I've got a signature for a method that looks like this:
private IEnumerable BuildCustomerUpdatePlan(List localCacheChangedCustomers, List crmChangedCustomers){}
When I look at the moled object, the syntax (IntelliSense) of how to call the method and test itis absolutely confusing to me and every time I give it a shot, I get compilation errors. I've looked through the basic tutorials provided on MSFT's site, but I simply don't get how to test a private method using Moles or how to deal with the return type and multiple parameters.
Unfortuantely I've been unable to find other good HOWTO's or threads demonstrating a more complex sample than just working with a simple Add() method that spits out an INT and accepts an INT. :(
Tips?

In your testing project, first make sure you add a Moles assembly corresponding to the assembly-under-test. You'll also want to add an using statement of the assembly-under-test with .Moles appended so you can use the moled assembly.
Moles changes the names of the classes and methods to the form M[Original Class Name].[Original Method Name][typeof param1][typeof param2].... In your case a detour for that method could look like MClass.BuildCustomerUpdatePlanListList = (List x, List y) => { [code]};. That defines an anonymous method that takes two Lists as parameters and you'd put whatever code wanted in the function. Just make sure that you return an IEnumerable in that anonymous method.
Here's an example using Moles to detour Directory.GetFiles:
using System.IO.Moles;
[assembly: MoledType(typeof(System.IO.Directory))]
...
MDirectory.GetFilesStringString = (string x, string y) => new string[0];
Since the Directory class is a member of System.IO I use using System.IO.Moles; to specify that I want to use moled members of the assembly.
Moles requires you to specify the types Moled: [assembly: MoledType(typeof(System.IO.Directory))] does the job.
Finally, Directory.GetFiles takes two strings as parameters and returns a string array. To detour the method into returning the equivalent of no files found, the moled method just returns new string[0]. Curly braces are needed if you want multiple lines in the anonymous method and, if not detouring a void method, a return statement that matches the type the original method would return.

Related

Modern equivalent of the superiorto() function

I'm working on rewriting an old MATLAB package. As part of that rewrite I'm updating two classes (lets call them old_class1 and old_class2) defined using the class() function to classes defined with classdef.
The definition of old_class1 contains the line superiorto('old_class2'). This function is not allowed in a constructor defined with classdef, but I am unable to find any equivalent. How do I create functionality equivalent to superiorto() in a class defined with classdef?
superiorto is no longer available in MATLAB, but I was able to find a copy of old documentation that indicates it was used to determine which object's method was called when multiple different classes were given as function arguments. For example, given obj1=class1() and obj2=class2(), with the class1 constructor containing superiorto('class2'), would cause function(obj1,obj2) to callclass1.function, rather thanclass2.function`.
With modern classdef functionality, the same can be accomplished by setting the InferiorClasses property:
classdef (InferiorClasses = {?class2}) class1

Why do some Matlab class methods require "apparently" unnecessary output argument

After evolving my project code for months, I've finally hit a need to define a new class. Having to romp through my previous class definitions as a refresher of the conventions, I noticed that all constructors and property setters all have an output argument, even though nothing is assigned to it, e.g.:
function o = myConstructor( arg1, arg2, ... )
function o = set.SomeProperty( o, arg1 )
I've been looking through the documentation for upward of an hour without finding the explanation for this. It doesn't look like it depends on whether a function is defined in the class definition file or in its own separate m-file.
Can anyone please explain?
The best place to start is the documentation "Comparison of Handle and Value Classes". From the very top:
A value class constructor returns an object that is associated with the variable to which it is assigned. If you reassign this variable, MATLABĀ® creates an independent copy of the original object. If you pass this variable to a function to modify it, the function must return the modified object as an output argument.
A handle class constructor returns a handle object that is a reference to the object created. You can assign the handle object to multiple variables or pass it to functions without causing MATLAB to make a copy of the original object. A function that modifies a handle object passed as an input argument does not need to return the object.
In other words, value classes need to return a modified object (which is a new object distinct from the original), while handle classes don't. The constructor of either class will always have to return an object, since it is actually constructing it.
Some good additional reading is "Which Kind of Class to Use", which links to a couple helpful examples of each type of class object. Looking at the DocPolynom value class example, you can see that property set methods have to return the modified object, while the dlnode handle class example only requires an output for its constructor. Note that you could still return an object from a handle class method (if desired), but it's not required.

Swift dynamic function call from Any

I'm trying to make a generic testing interface that takes an function, fills out the function signature parameters via introspection, and then runs the arbitrary function.
Test(function: <Any>)
{
let signature = Mirror(reflecting:function)
...
}
In Swift 3 I can get the function signature from reflection. With the Zewo library I have KVO & KVC built on top of the swift 3 Metadata. So far so good.
But the last two steps I'm tripping over: Building up a arbitrary parameter list and dynamically calling Function.
Is there a generic way to do this? (pointers are allowed!) Now that tuple splat is gone (and it was never dynamic in the first place), are there any exposed methods for dynamic arguments, or popping arguments onto the stack dynamically or another language provision?

Dynamic Proxy using Scalas new Dynamic Type

Is it possible to create an AOP like interceptor using Scalas new Dynamic Type feature? For example: Would it be possible to create a generic stopwatch interceptor that could be mixed in with arbitrary types to profile my code? Or would I still have to use AspectJ?
I'm pretty sure Dynamic is only used when the object you're selecting on doesn't already have what you're selecting:
From the nightly scaladoc:
Instances x of this trait allow calls x.meth(args) for arbitrary method names meth and argument lists args. If a call is not natively supported by x, it is rewritten to x.invokeDynamic("meth", args)
Note that since the documentation was written, the method has been renamed applyDynamic.
No.
In order for a dynamic object to be supplied as a parameter, it'll need to have the expected type - which means inheriting from the class you want to proxy, or from the appropriate superclass / interface.
As soon as you do this, it'll have the relevant methods statically provided, so applyDynamic would never be considered.
I think your odds are bad. Scala will call applyDynamic only if there is no static match on the method call:
class Slow {
def doStuff = //slow stuff
}
var slow = new Slow with DynamicTimer
slow.doStuff
In the example above, scalac won't call applyDynamic because it statically resolved your call to doStuff. It will only fall through to applyDynamic if the method you are calling matches none of the names of methods on the type.

RhinoMocks - Pass Action<T> as parameter

In RhinoMocks, there's Stub extension method, that takes Action<T>. For some reason this:
CurrentInvoice.Stub(i => i.TaxYear).Return(1);
works great, but this:
CurrentInvoice.Stub(new Action<Invoice>(i => i.TaxYear)).Return(1);
produces the compiler error:
Only assignment, call, increment, decrement, and new object expressions can be used as a statement
The intellisense for this method explicitly says that it expects Action<Invoice>, so I can't understand why the first works, but not the second.
The main relevance of this is that I'd like to be able to pass some of these configuration lambdas as parameters to a method, and I run into this same issue.
Thanks
Are you sure you're not accidentally using an overload for Stub which takes a Func<T, TResult> in the first line? I can't see why the first call would work otherwise.
Do you have a link to API documentation?