On 2013-03-25, at 21:24, Denis Kudriashov <dionisiydk@gmail.com> wrote:
Hello
I think you read about Mocketry and know that It provides same "should syntax" DSL like project Phexample.
There is problem between two projects. We both implement #should message in Object class. So when somebody want Phexample Mocketry become broken and vice versa.
In the past I actually only read about Phexample tests reusage idea with #given message. And I didn't know that It provides "should syntax" too. Now I read about it and look at code (thank's Yuriy Tymchuk) and I have some suggestions about it.
First few words about state of Mocketry project.
Mocketry is not based on SSpec (I was google such wrong opinion). It is just implement SSpec idea about executable specifications and "should syntax". And specifications part with DSL was extracted from Mocketry to StateSpecs project. So Mocketry is only about mocks and behaviour specs.
Idea of executable specifications is not about replacement "assert syntax" with "should syntax". It is about building reusable first class objects which can validate domain objects. For example there are EqualitySpec, ElementsCountSpec, ClassSpec. All this specs present "valid state" of objects. They know how to validate objects. State specs can be used in tests, UI and any other domain where you want put descriptions about what it mean "valid object". I start use StateSpecs in Presenty to build object editor. With specs I put requirements on model aspects. I am sure Magritte provides something similar in description objects.
So StateSpecs solve very general problem: how to describe validation rules for objects and how to make such descriptions reusable. To make it convenient and readable StateSpecs provides two kind of DSL:
- should syntax to immediately check object state - first class words to create spec instances with more readable way: Instance of: SomeClass, Equal to: #some, Containing item: arrayItem and others
First option can be used in tests instead #assert: expressions. Last can be used in mock message arguments.
StateSpecs provide very simple way to extend it DSL based on pragmas:
Instance of: aClass <syntax: #(be an instance of:)> ^ClassSpec for: aClass
Equal to: anObject <syntax: #(equal:)> <syntax: #(be equal:)> ^self return: (EqualitySpec pattern: anObject)
Containing item: anObject <syntax: #(include:)> ^ElementContainmentSpec requiredElement: anObject
And with this you can write:
object should be an instance of: SomeClass object should equal: #some object should be equal: #some array should include: item.
So with such approach both kind of DSL extended at one place.
Ok. Now my main suggestion. Let's Phexample use StateSpecs for "should syntax". I can provide all "should protocol" of Phexample in StateSpecs. So it will be transparent for current users. It just few extra pragmas and classes in StateSpecs-DSL package. Maybe it is already done by Yuriy Tymchuk. With such integration both projects will just improved.
What do you think?
humm I have ambigous feelings about that. Definitely StateSpec looks more mature and can be used in a more flexible way. But I am not a big fan of the pragma magic. Why? It breaks all tools for me :/. If I see a message send I want to be able to: - browse it, so I can see who implements it? - debug it directly to get to the real method. SateSpec does indeed help writing readable code by allowing almost grammatically correct sentences. However I don't think this is the way to program. I am a big fan of stupid english: `foo should isKindOf: Bar` vs. `foo should be an instance of: Bar` If I want to figure out how the first one works, I can simply browse the implementors of #should and/or #isKindOf: where is the StateSpec version I am lost. I have to rely on "contains string literal" to get the sources, for me that is very strange. So personally I would go for the simple solution that doesn't introduce yet another indirection meta-level using the pragmas. For me, complex DSLs only work if you write the proper debugging tools for it. Sorry for so much negative energy :) but you can try to convince me otherwise :)