[BUG] [Kotlin] Data class must have at least one primary constructor parameter

[alex-hedley]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

I'm trying to generate a Kotlin class from a Swagger Spec.

Actual Kotlin Class
class FooList : MutableList<Foo> by ArrayList()

OpenAPI Generator output
data class FooList () : kotlin.collections.ArrayList<Foo>()

Build Error:

Data class must have at least one primary constructor parameter

openapi-generator version

6.3.0

Generation Details

import org.openapitools.generator.gradle.plugin.tasks.GenerateTask

plugins {
  id("org.openapi.generator") version "6.3.0"
}

tasks.register<GenerateTask>() { ... }

Steps to reproduce

...

Suggest a fix

Tried adding No-arg compiler plugin but it would prob need to be ran at a certain time in the build?

plugins {
// id("org.jetbrains.kotlin.plugin.noarg") version "1.8.10"
  kotlin("plugin.noarg") version "1.7.21"
}

noArg {
  annotation("com.example.FooList")
}

[sumowrestler]

Also seeing this in my case there is no annotation to target in the noarg plugin.

[Perondas]

I am having the same issue trying to generate a client for this spec.
The data classes: End, EndDate, Start, StartDate and LocationInner are all missing a constructor.