[BUG] java.lang.IllegalArgumentException: No container found for type parameter 'FROM' of 'CLASS IR_EXTERNAL_DECLARATION_STUB CLASS name:ObjectMappie modality:ABSTRACT visibility [...] when trying to compile for iOS (compileKotlinIosSimulatorArm64)

[lkjh654]

Describe the bug
Version 1.1.0 used, compilation fails with:

error: java.lang.IllegalArgumentException: No container found for type parameter 'FROM' of 'CLASS IR_EXTERNAL_DECLARATION_STUB CLASS name:ObjectMappie modality:ABSTRACT visibility:public superTypes:[tech.mappie.api.Mappie<TO of tech.mappie.api.ObjectMappie>]'
	at org.jetbrains.kotlin.backend.common.serialization.mangle.BaseKotlinMangleComputer.mangleTypeParameterReference(BaseKotlinMangleComputer.kt:226)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.ir.IrMangleComputer.mangleType(IrMangleComputer.kt:120)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.ir.IrMangleComputer.mangleType(IrMangleComputer.kt:25)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.BaseKotlinMangleComputer.mangleValueParameter(BaseKotlinMangleComputer.kt:256)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.BaseKotlinMangleComputer.mangleSignature$lambda$4(BaseKotlinMangleComputer.kt:187)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.MangleUtilsKt.collectForMangler(mangleUtils.kt:25)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.BaseKotlinMangleComputer.mangleSignature(BaseKotlinMangleComputer.kt:182)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.BaseKotlinMangleComputer.mangleFunction(BaseKotlinMangleComputer.kt:155)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.ir.IrMangleComputer.access$mangleFunction(IrMangleComputer.kt:25)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.ir.IrMangleComputer$Visitor.visitSimpleFunction(IrMangleComputer.kt:248)
	at org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid$DefaultImpls.visitSimpleFunction(IrElementVisitorVoid.kt:144)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.ir.IrMangleComputer$Visitor.visitSimpleFunction(IrMangleComputer.kt:136)
	at org.jetbrains.kotlin.backend.common.serialization.mangle.ir.IrMangleComputer$Visitor.visitSimpleFunction(IrMangleComputer.kt:136)
	at org.jetbrains.kotlin.ir.declarations.IrSimpleFunction.accept(IrSimpleFunction.kt:39)
	at org.jetbrains.kotlin.ir.visitors.IrVisitorsKt.acceptVoid(IrVisitors.kt:11)

To Reproduce
Run compileKotlinIosSimulatorArm64 task for KMP project

Expected behavior
Compilation tasks is successful

Additional context
The library works fine on Android. The dependency was added in: commonMain.dependencies {} block. Compiler version: 2.1.0.

[stefankoppier]

Hi @lkjh654, I'm sad to hear another problem occurs. I just ran the existing tests on mac, but I have few mac specific tests.

Are you able to pinpoint and share a mapper gives this problem? You could do this by changing the implementation of the mappers to from either mapping { ... } or no implementation to something which results in no code being generated. e.g. TODO() until no compilation error occurs.

The line tech.mappie.api.Mappie<TO of tech.mappie.api.ObjectMappie> also stands out, do you have a mapper which has a target type of another mapper?

[lkjh654]

Hi,

this is a mapper that can be used to reproduce the problem:

import tech.mappie.api.ObjectMappie

object AMapper : ObjectMappie<AIn, AOut>()
//object BMapper : ObjectMappie<BIn, BOut>() // works fine if commented out on Android, fails on iOS

data class AIn(val b: BIn)
data class AOut(val b: BOut)

data class BIn(val value: String)
data class BOut(val value: String)

Basically if a mapper for type B is not explicitly defined the compilation fails on iOS however it works fine on Android. Also if the compilation fails there is no way to figure out which mapper is missing.

[stefankoppier]

Thanks @lkjh654. I managed to reproduce this in a test from Gradle.

I tried to rewrite the (test) compilation dsl to allow in-process multiplatform compilation, but this doesn't seem to be supported. This means that finding the issue might be hard, but I am looking into it.

For "Also if the compilation fails there is no way to figure out which mapper is missing.", this is sometimes the case if Mappie itself thinks everything went well, but something is rejected by the compiler. These should never occur, and the compiler should either succeed or mappie should report the actual problem. A compiler exception like this is considered a bug.

[stefankoppier]

Hi @lkjh654. I just made a fix for this issue. I will create release 1.1.1 right after it is merged. Thanks for the report.

[lkjh654]

@stefankoppier
I actually still face the exact same problem for some mappers. The case seems to be the same: all works fine on Android and it fails during compilation on iOS. I'm using the latest version "2.1.20-1.2.1". For iOS I need to declare all mappers explicitly but for Android it's not necessary. From the compilation error it's not possible to figure out which mapper is actually missing.

One case of a mapper for I face this error is a mapper that is supposed to map a collection of "child" classes, but I'm not sure if that's somehow related.

[lkjh654]

Side question: is it somehow possible to preview the generated code?

[stefankoppier]

HI @lkjh654. I'm sad to hear that. I'm looking into it and I will let you know when I'm able to reproduce this and have a fix.

[stefankoppier]

Side question: is it somehow possible to preview the generated code?

Currently, no. The code is generated as an intermediate representation. The issue that is arising occurs in a separate part of the compiler. So logging the generated code will not pinpoint the exact mapper causing the compilation error. But beside that, a report that contains all generated mappers would be nice (also for my own debugging purposes).