[IR generator] Don't use kotlinpoet for auto-generating IR tree classes

KT-61970 Fixed
KT-61703 Fixed

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

@@ -69,7 +69,7 @@ abstract class AbstractElementPrinter<Element : AbstractElement<Element, Field>,
 
             if (body.isNotEmpty()) {
                 println(" {")
-                print(body)
+                print(body.trimStart('\n'))
                 print("}")
             }
             println()

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

@@ -32,6 +32,10 @@ abstract class AbstractField {
     open val withGetter: Boolean get() = false
     open val customSetter: String? get() = null
 
+    var deprecation: Deprecated? = null
+
+    var visibility: Visibility = Visibility.PUBLIC
+
     var fromParent: Boolean = false
 
     open val defaultValueInImplementation: String? get() = null

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

@@ -35,6 +35,17 @@ abstract class AbstractFieldPrinter<Field : AbstractField>(
     ) {
         printer.run {
             printKDoc(field.kDoc)
+
+            field.deprecation?.let {
+                println("@Deprecated(")
+                withIndent {
+                    println("message = \"", it.message, "\",")
+                    println("replaceWith = ReplaceWith(\"", it.replaceWith.expression, "\"),")
+                    println("level = DeprecationLevel.", it.level.name, ",")
+                }
+                println(")")
+            }
+
             if (field.isVolatile) {
                 println("@", type<Volatile>().render())
             }
@@ -50,6 +61,10 @@ abstract class AbstractFieldPrinter<Field : AbstractField>(
                 }
             }
 
+            if (field.visibility != Visibility.PUBLIC) {
+                print(field.visibility.name.toLowerCaseAsciiOnly(), " ")
+            }
+
             modality?.let {
                 print(it.name.toLowerCaseAsciiOnly(), " ")
             }

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

@@ -68,12 +68,20 @@ class ImportCollector(currentPackage: String) {
         addImport(packageName, "*")
     }
 
-    fun printAllImports(printer: Appendable) {
+    /**
+     * Prints all the collected imports in alphabetical order.
+     *
+     * @return `true` if at least one import was printed, `false` if no imports were printed.
+     */
+    fun printAllImports(printer: Appendable): Boolean {
+        var atLeastOneImport = false
         for ((packageName, entities) in imports) {
             for (entity in entities) {
+                atLeastOneImport = true
                 printer.append("import ", packageName, ".", entity, "\n")
             }
         }
+        return atLeastOneImport
     }
 
     fun addAllImports(importables: Collection<Importable>) {

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

@@ -0,0 +1,10 @@
+/*
+ * 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
+
+enum class Visibility {
+    PUBLIC, PROTECTED, INTERNAL, PRIVATE
+}

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

@@ -45,7 +45,9 @@ fun printGeneratedType(
             }
             appendLine("package $packageName")
             appendLine()
-            importCollector.printAllImports(this)
+            if (importCollector.printAllImports(this)) {
+                appendLine()
+            }
             append(stringBuilder)
         }
     )