Is there any way to do mock argument capturing in Spock

Question

I have looked around and tried different things to no avail. The examples out there on the interwebs are few, and IMHO pretty simple. My use case:

(the 'itocNetworkHandler' below is the mock)

when: "we're doing stuff"
    StandardResponse response = cms.doCardStuff("123", "111", order)
....
then: "we get proper calls and response object"
    1 * cms.itocNetworkHandler.doNetworkCall(
            { it instanceof ReplacementRequestRecord
            }, StandardResponseRecord.class) >> record

I would like to store away the parameter ('it') to the "doNetworkCall" on the mock.

The reason i want the parameter is because the object i'm testing is supposed to take my in parameters, do stuff, create a new object and pass that one to my mock. I want to make sure that the created object looks the way its supposed to.

Pointers much appreciated.

Spoilage

Why do you want to store the argument? What will you do with it? – Apivorous

I clarified above why i need it. – Spoilage

Answer 1

You can capture an argument as follows:

// must be declared before when-block (or inside Specification.interaction {})
def captured

when:
...

then:
1 * mock.doNetworkCall(...) >> { record, recordClass -> 
    // save the argument
    captured = record
    ...
}
// use the saved argument
captured == ...

That said, often there is a simpler solution such as checking the expected record right in the argument constraint (e.g. ...doNetworkCall( { it == ... } )).

Apivorous

Thanks, works. The reason i dont want it in "it ==" etc. is that i want to lots of checks, and i think its much tidier to have all asserts in the end, if you see what i mean. – Spoilage

You could put the checks into a helper method, and call the helper method from the argument constraint. – Apivorous

Yeah, thats a possibility. I think i like them in the end though. It feels a little bit "sneaky" to do the asserts within the parameter block, for readability i like them in the end. Or perhaps i'm just not used to the lingo. – Spoilage

I have found it impossible to access the captured argument outside of the closure, regardless of where the variable is defined. – Pompidou

I couldn't figure out how to break up the arguments in the closure as in the example code. I had to do 1 * mock.doNetworkCall(_) >> { arguments -> captured = arguments.get(0)} – Washerwoman