[FIR generator] Remove unused class ImplementationWithArg

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/context/AbstractFirTreeImplementationConfigurator.kt

@@ -27,7 +27,6 @@ abstract class AbstractFirTreeImplementationConfigurator {
         } ?: Implementation(element, name)
         val context = ImplementationContext(implementation)
         context.apply(config)
-        implementation.updateMutabilityAccordingParents()
         elementsWithImpl += element
         return implementation
     }
@@ -77,19 +76,6 @@ abstract class AbstractFirTreeImplementationConfigurator {
             return implementation.getField(name)
         }
 
-        inner class ParentsHolder {
-            operator fun plusAssign(parent: Implementation) {
-                implementation.addParent(parent)
-            }
-
-            operator fun plusAssign(parent: ImplementationWithArg) {
-                implementation.addParent(parent.implementation, parent.argument)
-                parent.argument?.let { useTypes(it) }
-            }
-        }
-
-        val parents = ParentsHolder()
-
         fun optInToInternals() {
             implementation.requiresOptIn = true
         }

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/model/Implementation.kt

@@ -7,18 +7,8 @@ package org.jetbrains.kotlin.fir.tree.generator.model
 
 import org.jetbrains.kotlin.generators.tree.*
 
-class ImplementationWithArg(
-    val implementation: Implementation,
-    val argument: Importable?
-) : FieldContainer by implementation, ImplementationKindOwner by implementation {
-    val element: Element get() = implementation.element
-}
-
 class Implementation(val element: Element, val name: String?) : FieldContainer, ImplementationKindOwner {
-    private val _parents = mutableListOf<ImplementationWithArg>()
-    val parents: List<ImplementationWithArg> get() = _parents
-
-    override val allParents: List<ImplementationKindOwner> get() = listOf(element) + parents
+    override val allParents: List<ImplementationKindOwner> get() = listOf(element)
     val isDefault = name == null
     override val typeName = name ?: (element.typeName + "Impl")
 
@@ -80,26 +70,10 @@ class Implementation(val element: Element, val name: String?) : FieldContainer,
     override val transformableChildren: List<FieldWithDefault>
         get() = walkableChildren.filter { it.isMutable }
 
-    fun addParent(parent: Implementation, arg: Importable? = null) {
-        _parents += ImplementationWithArg(parent, arg)
-    }
-
     override fun get(fieldName: String): FieldWithDefault? {
         return allFields.firstOrNull { it.name == fieldName }
     }
 
-    fun updateMutabilityAccordingParents() {
-        for (parent in parents) {
-            for (field in allFields) {
-                val fieldFromParent = parent[field.name] ?: continue
-                field.isMutable = field.isMutable || fieldFromParent.isMutable
-                if (field.isMutable && field.customSetter == null) {
-                    field.withGetter = false
-                }
-            }
-        }
-    }
-
     val fieldsWithoutDefault by lazy { allFields.filter { it.defaultValueInImplementation == null } }
     val fieldsWithDefault by lazy { allFields.filter { it.defaultValueInImplementation != null } }
 

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/util/configureInterfacesAndAbstractClasses.kt

@@ -6,17 +6,13 @@
 package org.jetbrains.kotlin.fir.tree.generator.util
 
 import org.jetbrains.kotlin.fir.tree.generator.context.AbstractFirTreeBuilder
-import org.jetbrains.kotlin.fir.tree.generator.model.*
+import org.jetbrains.kotlin.fir.tree.generator.model.Implementation
 import org.jetbrains.kotlin.generators.tree.ImplementationKindOwner
-import org.jetbrains.kotlin.generators.tree.ImplementationKind
 import org.jetbrains.kotlin.generators.tree.InterfaceAndAbstractClassConfigurator
 
 private class FirInterfaceAndAbstractClassConfigurator(builder: AbstractFirTreeBuilder) : InterfaceAndAbstractClassConfigurator() {
 
-    override val elements = (builder.elements + builder.elements.flatMap { it.allImplementations }).map { it.origin }
-
-    override val ImplementationKindOwner.origin: ImplementationKindOwner
-        get() = if (this is ImplementationWithArg) implementation else this
+    override val elements: List<ImplementationKindOwner> = (builder.elements + builder.elements.flatMap { it.allImplementations })
 
     override fun shouldBeFinalClass(element: ImplementationKindOwner, allParents: Set<ImplementationKindOwner>): Boolean =
         element is Implementation && element !in allParents

generators/tree-generator-common/src/org/jetbrains/kotlin/generators/tree/InterfaceAndAbstractClassConfigurator.kt

@@ -18,16 +18,13 @@ abstract class InterfaceAndAbstractClassConfigurator {
             get() = element.allParents.map(::NodeImpl)
 
         override val origin: NodeImpl
-            get() = if (element.origin == element) this else NodeImpl(element.origin)
+            get() = this
 
         override fun equals(other: Any?): Boolean = other is NodeImpl && element == other.element
 
         override fun hashCode(): Int = element.hashCode()
     }
 
-    protected open val ImplementationKindOwner.origin: ImplementationKindOwner
-        get() = this
-
     /**
      * The list of elements of the tree to infer their [ImplementationKind].
      */