Is there any utility for turning a hierarchy Kotlin data classes into code. Want to fetch some data...

# stdlib

[yschimke]

Is there any utility for turning a hierarchy Kotlin data classes into code. Want to fetch some data from an API, and turn it into executable code for test fixtures.

[Zac Sweers]

not a joke - ChatGPT is actually excellent at this

[yschimke]

Give it the data classes, ask for better toString values.

[darkmoon_uk]

I'm not sure exactly what you mean but it sounds like you want to serialise your classes; in which case I recommend kotlinx.serialization library.

[yschimke]

No, I meant code I can copy and paste into my IDE to recreate a data class that would be exactly equal.

[yschimke]

I think ruby had an inspect method

[yschimke]

I don't need perfect, or handling all possible types. Just knowing to quote strings correctly

[Joffrey]

Data classes are already code, though. Do you mean you want to turn JSON into code that creates data class instances with the same data?

[yschimke]

I have an instance of an arbitrary data class at runtime. I want to turn it into a string I can put into my code to reinflate later

[Joffrey]

Ah I see. I think someone has asked this question some time ago, but I don't remember the outcome

[darkmoon_uk]

@yschimke are you sure you don't want kotlinx.serialization

[darkmoon_uk]

Turning instances of data classes into strings that can be reinflated later on is kind of it's thing

[yschimke]

Maybe, but I don't want to have to use kotlinx serialisation on the other side. Just copy and paste.

[yschimke]

I have other solutions. More curious if an inspect like operation is supported.

[yschimke]

I'd like the final form to be affected by refactoring, for example

[darkmoon_uk]

I think we need an example. I can't be alone in feeling I haven't fully grasped what you're looking for.

[yschimke]

val conferenceList = GetConferencesQuery.ConferenceList(conferences = listOf(
        GetConferencesQuery.Conference(
            "kotlinconf2023",
            listOf(
                LocalDate.parse("2023-04-12"),
                LocalDate.parse("2023-04-13"),
                LocalDate.parse("2023-04-14")
            ),
            "KotlinConf 2023"
        )
...

val textFixtureInspector = TestFixtureInspector()

println(textFixtureInspector.inspect(conferenceList))

[yschimke]

And that output

[yschimke]

GetConferencesQuery.ConferenceList(conferences = listOf(
        GetConferencesQuery.Conference(
            id = "kotlinconf2023",
            dates = listOf(
                LocalDate.parse("2023-04-12"),
                LocalDate.parse("2023-04-13"),
                LocalDate.parse("2023-04-14")
            ),
            name = "KotlinConf 2023"
        )