FIR: introduce FirLazyBlock node

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousFunction.kt

@@ -53,6 +53,8 @@ abstract class FirAnonymousFunction : FirFunction<FirAnonymousFunction>, FirExpr
 
     abstract override fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
 
+    abstract override fun replaceBody(newBody: FirBlock?)
+
     abstract override fun replaceTypeRef(newTypeRef: FirTypeRef)
 
     abstract fun replaceInvocationKind(newInvocationKind: EventOccurrencesRange?)

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirConstructor.kt

@@ -53,6 +53,8 @@ abstract class FirConstructor : FirPureAbstractElement(), FirFunction<FirConstru
 
     abstract override fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
 
+    abstract override fun replaceBody(newBody: FirBlock?)
+
     abstract override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirConstructor
 
     abstract override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirConstructor

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirErrorFunction.kt

@@ -50,6 +50,8 @@ abstract class FirErrorFunction : FirPureAbstractElement(), FirFunction<FirError
 
     abstract override fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
 
+    abstract override fun replaceBody(newBody: FirBlock?)
+
     abstract override fun <D> transformAnnotations(transformer: FirTransformer<D>, data: D): FirErrorFunction
 
     abstract override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirErrorFunction

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirFunction.kt

@@ -48,6 +48,8 @@ interface FirFunction<F : FirFunction<F>> : FirCallableDeclaration<F>, FirTarget
 
     fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
 
+    fun replaceBody(newBody: FirBlock?)
+
     override fun <D> transformAnnotations(transformer: FirTransformer<D>, data: D): FirFunction<F>
 
     override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirFunction<F>

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirPropertyAccessor.kt

@@ -54,6 +54,8 @@ abstract class FirPropertyAccessor : FirPureAbstractElement(), FirFunction<FirPr
 
     abstract override fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
 
+    abstract override fun replaceBody(newBody: FirBlock?)
+
     abstract override fun replaceContractDescription(newContractDescription: FirContractDescription)
 
     abstract override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirPropertyAccessor

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirSimpleFunction.kt

@@ -54,6 +54,8 @@ abstract class FirSimpleFunction : FirPureAbstractElement(), FirFunction<FirSimp
 
     abstract override fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
 
+    abstract override fun replaceBody(newBody: FirBlock?)
+
     abstract override fun replaceContractDescription(newContractDescription: FirContractDescription)
 
     abstract override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirSimpleFunction

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousFunctionImpl.kt

@@ -127,6 +127,10 @@ internal class FirAnonymousFunctionImpl(
         valueParameters.addAll(newValueParameters)
     }
 
+    override fun replaceBody(newBody: FirBlock?) {
+        body = newBody
+    }
+
     override fun replaceTypeRef(newTypeRef: FirTypeRef) {
         typeRef = newTypeRef
     }

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirConstructorImpl.kt

@@ -137,4 +137,8 @@ internal class FirConstructorImpl(
         valueParameters.clear()
         valueParameters.addAll(newValueParameters)
     }
+
+    override fun replaceBody(newBody: FirBlock?) {
+        body = newBody
+    }
 }

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirErrorFunctionImpl.kt

@@ -111,4 +111,6 @@ internal class FirErrorFunctionImpl(
         valueParameters.clear()
         valueParameters.addAll(newValueParameters)
     }
+
+    override fun replaceBody(newBody: FirBlock?) {}
 }

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPrimaryConstructor.kt

@@ -137,4 +137,8 @@ internal class FirPrimaryConstructor(
         valueParameters.clear()
         valueParameters.addAll(newValueParameters)
     }
+
+    override fun replaceBody(newBody: FirBlock?) {
+        body = newBody
+    }
 }

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyAccessorImpl.kt

@@ -136,6 +136,10 @@ open class FirPropertyAccessorImpl @FirImplementationDetail constructor(
         valueParameters.addAll(newValueParameters)
     }
 
+    override fun replaceBody(newBody: FirBlock?) {
+        body = newBody
+    }
+
     override fun replaceContractDescription(newContractDescription: FirContractDescription) {
         contractDescription = newContractDescription
     }

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSimpleFunctionImpl.kt

@@ -140,6 +140,10 @@ open class FirSimpleFunctionImpl @FirImplementationDetail constructor(
         valueParameters.addAll(newValueParameters)
     }
 
+    override fun replaceBody(newBody: FirBlock?) {
+        body = newBody
+    }
+
     override fun replaceContractDescription(newContractDescription: FirContractDescription) {
         contractDescription = newContractDescription
     }

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirLazyBlockBuilder.kt

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2010-2020 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.fir.expressions.builder
+
+import kotlin.contracts.*
+import org.jetbrains.kotlin.fir.FirImplementationDetail
+import org.jetbrains.kotlin.fir.FirSourceElement
+import org.jetbrains.kotlin.fir.builder.FirAnnotationContainerBuilder
+import org.jetbrains.kotlin.fir.builder.FirBuilderDsl
+import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
+import org.jetbrains.kotlin.fir.expressions.FirBlock
+import org.jetbrains.kotlin.fir.expressions.FirStatement
+import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
+import org.jetbrains.kotlin.fir.expressions.impl.FirLazyBlock
+import org.jetbrains.kotlin.fir.types.FirTypeRef
+import org.jetbrains.kotlin.fir.visitors.*
+
+/*
+ * This file was generated automatically
+ * DO NOT MODIFY IT MANUALLY
+ */
+
+@FirBuilderDsl
+class FirLazyBlockBuilder : FirAnnotationContainerBuilder, FirExpressionBuilder {
+    override var source: FirSourceElement? = null
+
+    @OptIn(FirImplementationDetail::class)
+    override fun build(): FirBlock {
+        return FirLazyBlock(
+            source,
+        )
+    }
+
+
+    @Deprecated("Modification of 'annotations' has no impact for FirLazyBlockBuilder", level = DeprecationLevel.HIDDEN)
+    override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
+
+    @Deprecated("Modification of 'typeRef' has no impact for FirLazyBlockBuilder", level = DeprecationLevel.HIDDEN)
+    override var typeRef: FirTypeRef
+        get() = throw IllegalStateException()
+        set(value) {
+            throw IllegalStateException()
+        }
+}
+
+@OptIn(ExperimentalContracts::class)
+inline fun buildLazyBlock(init: FirLazyBlockBuilder.() -> Unit = {}): FirBlock {
+    contract {
+        callsInPlace(init, kotlin.contracts.InvocationKind.EXACTLY_ONCE)
+    }
+    return FirLazyBlockBuilder().apply(init).build()
+}

compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirLazyBlock.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2010-2020 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.fir.expressions.impl
+
+import org.jetbrains.kotlin.fir.FirImplementationDetail
+import org.jetbrains.kotlin.fir.FirSourceElement
+import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
+import org.jetbrains.kotlin.fir.expressions.FirBlock
+import org.jetbrains.kotlin.fir.expressions.FirStatement
+import org.jetbrains.kotlin.fir.types.FirTypeRef
+import org.jetbrains.kotlin.fir.visitors.*
+
+/*
+ * This file was generated automatically
+ * DO NOT MODIFY IT MANUALLY
+ */
+
+class FirLazyBlock @FirImplementationDetail constructor(
+    override val source: FirSourceElement?,
+) : FirBlock() {
+    override val annotations: List<FirAnnotationCall> get() = error("FirLazyBlock should be calculated before accessing")
+    override val statements: List<FirStatement> get() = error("FirLazyBlock should be calculated before accessing")
+    override val typeRef: FirTypeRef get() = error("FirLazyBlock should be calculated before accessing")
+
+    override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
+    }
+
+    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirLazyBlock {
+        transformOtherChildren(transformer, data)
+        return this
+    }
+
+    override fun <D> transformAnnotations(transformer: FirTransformer<D>, data: D): FirLazyBlock {
+        return this
+    }
+
+    override fun <D> transformStatements(transformer: FirTransformer<D>, data: D): FirLazyBlock {
+        return this
+    }
+
+    override fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirLazyBlock {
+        return this
+    }
+
+    override fun replaceTypeRef(newTypeRef: FirTypeRef) {}
+}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirRenderer.kt

@@ -503,8 +503,11 @@ class FirRenderer(builder: StringBuilder, private val mode: RenderMode = RenderM
         anonymousInitializer.body?.renderBody()
     }
 
-    private fun FirBlock.renderBody(additionalStatements: List<FirStatement> = emptyList()) {
-        renderInBraces {
+    private fun FirBlock.renderBody(additionalStatements: List<FirStatement> = emptyList()) = when (this) {
+        is FirLazyBlock -> {
+            println(" { LAZY_BLOCK }")
+        }
+        else -> renderInBraces {
             for (statement in additionalStatements + statements) {
                 statement.accept(this@FirRenderer)
                 println()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/synthetic/FirSyntheticPropertyAccessor.kt

@@ -79,6 +79,10 @@ class FirSyntheticPropertyAccessor(
         contractDescription.accept(visitor, data)
     }
 
+    override fun replaceBody(newBody: FirBlock?) {
+        throw AssertionError("Transformation of synthetic property accessor isn't supported")
+    }
+
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirPropertyAccessorImpl {
         throw AssertionError("Transformation of synthetic property accessor isn't supported")
     }

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

@@ -47,8 +47,8 @@ object FieldSets {
     fun symbol(symbolClassName: String, argument: String? = null): Field =
         symbolWithPackage("fir.symbols.impl", symbolClassName, argument)
 
-    fun body(nullable: Boolean = false) =
-        field("body", block, nullable)
+    fun body(nullable: Boolean = false, withReplace: Boolean = false) =
+        field("body", block, nullable, withReplace = withReplace)
 
     val returnTypeRef =
         field("returnTypeRef", typeRef)

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

@@ -113,6 +113,23 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
             publicImplementation()
         }
 
+        impl(block, "FirLazyBlock") {
+            val error = """error("FirLazyBlock should be calculated before accessing")"""
+            default("statements") {
+                value = error
+                withGetter = true
+            }
+            default("annotations") {
+                value = error
+                withGetter = true
+            }
+            default("typeRef") {
+                value = error
+                withGetter = true
+            }
+            publicImplementation()
+        }
+
         impl(errorLoop) {
             default("block", "FirEmptyExpressionBlock()")
             default("condition", "FirErrorExpressionImpl(source, ConeStubDiagnostic(diagnostic))")

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

@@ -102,7 +102,7 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
             parentArg(callableDeclaration, "F", "F")
             +symbol("FirFunctionSymbol", "F")
             +fieldList(valueParameter, withReplace = true).withTransform()
-            +body(nullable = true).withTransform()
+            +body(nullable = true, withReplace = true).withTransform()
         }
 
         errorFunction.configure {