Spying on a lambda with receiver function?

[EdricChan03]

Is it possible to spy on a function that takes a lambda with receiver?

Attempting to do something like this:

fun blah(init: Thing.() -> Unit) = Thing().apply(init)

// In test
mockkStatic(::blah)
dslMock = spyk<Thing>()
every { blah(any()) } answers { dslMock.apply(firstArg()) }

Throws the following error:

java.lang.AbstractMethodError: Receiver class kotlin.jvm.functions.Function1$Subclass0 does not define or inherit an implementation of the resolved method 'abstract java.lang.Object invoke(java.lang.Object)' of interface kotlin.jvm.functions.Function1.

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A quick search in the issues here gives me the following comment to an unrelated issue:

#271 (comment)