[Kotlin][Spring] use flag delegatePattern together with skipDefaultInterface

[pstorch]

fix #19211 kotlin-spring flag delegatePattern together with skipDefaultInterface generates broken code

It internally splits the skipDefaultInterface into skipDefaultApiInterface and skipDefaultDelegateInterface depending on the delegatePattern option.

This way, if the delegatePattern is used, it keeps the Api interface complete (to be able to be used by the Controller class) and removes the default implementations on the Delegate interface instead.

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[wing328]

i ran gradle build in this folder but got

wing3@MSI MINGW64 ~/Code/openapi-generator/samples/server/petstore/kotlin-springboot-delegate-nodefaults (pstorch-kotlin_delegate_nodefaults_19211)
$ gradle build
Starting a Gradle Daemon (subsequent builds will be faster)

> Task :compileKotlin
e: C:\Users\wing3\Code\openapi-generator\samples\server\petstore\kotlin-springboot-delegate-nodefaults\src\main\kotlin\org\openapitools\api\PetApiController.kt: (10, 9): Platform declaration clash: The following declarations have the same JVM signature (getDelegate()Lorg/openapitools/api/PetApiDelegate;):
    fun `<get-delegate>`(): PetApiDelegate defined in org.openapitools.api.PetApiController
    fun getDelegate(): PetApiDelegate defined in org.openapitools.api.PetApiController
e: C:\Users\wing3\Code\openapi-generator\samples\server\petstore\kotlin-springboot-delegate-nodefaults\src\main\kotlin\org\openapitools\api\PetApiController.kt: (14, 5): Platform declaration clash: The following declarations have the same JVM signature (getDelegate()Lorg/openapitools/api/PetApiDelegate;):
    fun `<get-delegate>`(): PetApiDelegate defined in org.openapitools.api.PetApiController
    fun getDelegate(): PetApiDelegate defined in org.openapitools.api.PetApiController
e: C:\Users\wing3\Code\openapi-generator\samples\server\petstore\kotlin-springboot-delegate-nodefaults\src\main\kotlin\org\openapitools\api\StoreApiController.kt: (10, 9): Platform declaration clash: The following declarations have the same JVM signature (getDelegate()Lorg/openapitools/api/StoreApiDelegate;):
    fun `<get-delegate>`(): StoreApiDelegate defined in org.openapitools.api.StoreApiController
    fun getDelegate(): StoreApiDelegate defined in org.openapitools.api.StoreApiController
e: C:\Users\wing3\Code\openapi-generator\samples\server\petstore\kotlin-springboot-delegate-nodefaults\src\main\kotlin\org\openapitools\api\StoreApiController.kt: (14, 5): Platform declaration clash: The following declarations have the same JVM signature (getDelegate()Lorg/openapitools/api/StoreApiDelegate;):
    fun `<get-delegate>`(): StoreApiDelegate defined in org.openapitools.api.StoreApiController
    fun getDelegate(): StoreApiDelegate defined in org.openapitools.api.StoreApiController
e: C:\Users\wing3\Code\openapi-generator\samples\server\petstore\kotlin-springboot-delegate-nodefaults\src\main\kotlin\org\openapitools\api\UserApiController.kt: (10, 9): Platform declaration clash: The following declarations have the same JVM signature (getDelegate()Lorg/openapitools/api/UserApiDelegate;):
    fun `<get-delegate>`(): UserApiDelegate defined in org.openapitools.api.UserApiController
    fun getDelegate(): UserApiDelegate defined in org.openapitools.api.UserApiController
e: C:\Users\wing3\Code\openapi-generator\samples\server\petstore\kotlin-springboot-delegate-nodefaults\src\main\kotlin\org\openapitools\api\UserApiController.kt: (14, 5): Platform declaration clash: The following declarations have the same JVM signature (getDelegate()Lorg/openapitools/api/UserApiDelegate;):
    fun `<get-delegate>`(): UserApiDelegate defined in org.openapitools.api.UserApiController
    fun getDelegate(): UserApiDelegate defined in org.openapitools.api.UserApiController

can you please take a look when you've time?

can you also add the new folder to the workflow file: https://github.com/OpenAPITools/openapi-generator/blob/master/.github/workflows/samples-kotlin-server.yaml#L34 ?

[pstorch]

Thanks for the feedback. I've fixed it.

[wing328]

please refactor to

        {{#skipDefaultDelegateInterface}}
        private val delegate: {{classname}}Delegate
        {{/skipDefaultDelegateInterface}}
        {{^skipDefaultDelegateInterface}}
        delegate: {{classname}}Delegate?
        {{/skipDefaultDelegateInterface}}

to avoid empty line break

[pstorch]

fixed