[FIR generator] Move Field and FieldContainer to common module

This is a step towards commonizing the code generator between
FIR and IR: KT-61970

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

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.fir.tree.generator.model
 
+import org.jetbrains.kotlin.generators.tree.FieldContainer
 import org.jetbrains.kotlin.generators.tree.Importable
 
 private const val DEFAULT_BUILDER_PACKAGE = "org.jetbrains.kotlin.fir.tree.builder"

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

@@ -8,6 +8,7 @@ package org.jetbrains.kotlin.fir.tree.generator.model
 import org.jetbrains.kotlin.fir.tree.generator.printer.BASE_PACKAGE
 import org.jetbrains.kotlin.fir.tree.generator.printer.typeWithArguments
 import org.jetbrains.kotlin.fir.tree.generator.util.set
+import org.jetbrains.kotlin.generators.tree.FieldContainer
 import org.jetbrains.kotlin.generators.tree.Importable
 
 interface KindOwner : Importable {
@@ -15,11 +16,6 @@ interface KindOwner : Importable {
     val allParents: List<KindOwner>
 }
 
-interface FieldContainer {
-    val allFields: List<Field>
-    operator fun get(fieldName: String): Field?
-}
-
 interface AbstractElement : FieldContainer, KindOwner {
     val name: String
     val fields: Set<Field>

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

@@ -8,32 +8,20 @@ package org.jetbrains.kotlin.fir.tree.generator.model
 import org.jetbrains.kotlin.fir.tree.generator.printer.typeWithArguments
 import org.jetbrains.kotlin.generators.tree.ArbitraryImportable
 import org.jetbrains.kotlin.generators.tree.Importable
+import org.jetbrains.kotlin.generators.tree.AbstractField
 
-sealed class Field : Importable {
-    abstract val name: String
-    open val arguments = mutableListOf<Importable>()
-    abstract val nullable: Boolean
-    abstract var isVolatile: Boolean
-    abstract var isFinal: Boolean
-    abstract var isLateinit: Boolean
-    abstract var isParameter: Boolean
+sealed class Field : AbstractField() {
     open var withReplace: Boolean = false
     abstract val isFirType: Boolean
 
-    var fromParent: Boolean = false
     open var needsSeparateTransform: Boolean = false
     var parentHasSeparateTransform: Boolean = true
     open var needTransformInOtherChildren: Boolean = false
     open var customInitializationCall: String? = null
-    open val arbitraryImportables: MutableList<Importable> = mutableListOf()
-    open var optInAnnotation: ArbitraryImportable? = null
 
     open val defaultValueInImplementation: String? get() = null
-    abstract var isMutable: Boolean
     abstract var isMutableOrEmpty: Boolean
     open var isMutableInInterface: Boolean = false
-    open val withGetter: Boolean get() = false
-    open val customSetter: String? get() = null
     open val fromDelegate: Boolean get() = false
 
     open val overridenTypes: MutableSet<Importable> = mutableSetOf()
@@ -65,21 +53,6 @@ sealed class Field : Importable {
 
     protected abstract fun internalCopy(): Field
 
-    override fun toString(): String {
-        return name
-    }
-
-    override fun equals(other: Any?): Boolean {
-        if (this === other) return true
-        if (other == null) return false
-        if (javaClass != other.javaClass) return false
-        other as Field
-        return name == other.name
-    }
-
-    override fun hashCode(): Int {
-        return name.hashCode()
-    }
 }
 
 // ----------- Field with default -----------

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

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.tree.generator.model
 
 import org.jetbrains.kotlin.generators.tree.ArbitraryImportable
+import org.jetbrains.kotlin.generators.tree.FieldContainer
 import org.jetbrains.kotlin.generators.tree.Importable
 
 class ImplementationWithArg(

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

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.generators.tree
+
+abstract class AbstractField : Importable {
+
+    abstract val name: String
+
+    open val arguments = mutableListOf<Importable>()
+
+    abstract val nullable: Boolean
+
+    abstract var isVolatile: Boolean
+
+    abstract var isFinal: Boolean
+
+    abstract var isLateinit: Boolean
+
+    abstract var isParameter: Boolean
+
+    open val arbitraryImportables: MutableList<Importable> = mutableListOf()
+
+    open var optInAnnotation: ArbitraryImportable? = null
+
+    abstract var isMutable: Boolean
+    open val withGetter: Boolean get() = false
+    open val customSetter: String? get() = null
+
+    var fromParent: Boolean = false
+
+    override fun toString(): String {
+        return name
+    }
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other == null) return false
+        if (javaClass != other.javaClass) return false
+        other as AbstractField
+        return name == other.name
+    }
+
+    override fun hashCode(): Int {
+        return name.hashCode()
+    }
+}

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

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.generators.tree
+
+interface FieldContainer {
+    val allFields: List<AbstractField>
+    operator fun get(fieldName: String): AbstractField?
+}