I have a problem in a StringSpec using withData: `...

# kotest

[henrik]

I have a problem in a StringSpec using withData:

"should drop default port" {
            withData(
                "<http://hei:80>" to "<http://hei>",
                "<http://hei:88>" to "<http://hei:88>",
                "<https://hei:443>" to "<https://hei>",
                "<https://hei:448>" to "<https://hei:448>",
            ) { (input, expected) ->
                input.toUrl().toString() shouldBe expected
                input.toUri().toString() shouldBe expected
            }
        }

This gives me

Cannot add a root test after the spec has been instantiated: (<http://hei:80>, <http://hei>)
io.kotest.core.spec.InvalidDslException: Cannot add a root test after the spec has been instantiated: (<http://hei:80>, <http://hei>)
	at io.kotest.core.spec.DslDrivenSpec.add(DslDrivenSpec.kt:46)
	at io.kotest.core.spec.style.scopes.RootScopeKt.addTest(RootScope.kt:33)
	at io.kotest.datatest.RootKt.withData(root.kt:65)
	at io.kotest.datatest.RootKt.withData(root.kt:51)
	at io.kotest.datatest.RootKt.withData(root.kt:16)

Any ideas what I'm doing wrong?

[henrik]

Seems like it's not possible. I'll roll my own with listof(...).forEach(...) instead. It would have been a nice feature to have!

[Klitos Kyriacou]

You can use FreeSpec at a container level (using -):

class MySampleDataDrivenTest : FreeSpec({
       "should drop default port" - {
            withData(
                "<http://hei:80>" to "<http://hei>",
                "<http://hei:88>" to "<http://hei:88>",
                "<https://hei:443>" to "<https://hei>",
                "<https://hei:448>" to "<https://hei:448>",
            ) { (input, expected) ->
                input.toUrl().toString() shouldBe expected
                input.toUri().toString() shouldBe expected
            }
        }
})

[henrik]

-!

[henrik]

interesting 🙂

[henrik]

thanks!

[henrik]

Would have been nice if this was mentioned on https://kotest.io/docs/framework/datatesting/data-driven-testing.html

[Klitos Kyriacou]

To be fair, it says "data tests can be nested inside any number of containers. But this is optional, you can define data tests at the root level as well." However, I agree that it's not immediately obvious, and I've found that the terminology is not entirely clear (e.g. it took me some time before I understood the term "container").

[henrik]

I realize I still don't understand kotest's definition of a container, although I haven't really tried that hard. I'll try to improve!