FIR: refactor destructuring declaration building helpers

rename them since they generate variables with initialization, rather
than arbitrary statements, and this fact is used in scripts
and also add initialization helper, used for scripting support too.

compiler/fir/raw-fir/light-tree2fir/src/org/jetbrains/kotlin/fir/lightTree/fir/DestructuringDeclaration.kt

@@ -10,7 +10,7 @@ import org.jetbrains.kotlin.fir.FirModuleData
 import org.jetbrains.kotlin.fir.builder.AbstractRawFirBuilder
 import org.jetbrains.kotlin.fir.builder.DestructuringContext
 import org.jetbrains.kotlin.fir.builder.FirAnnotationContainerBuilder
-import org.jetbrains.kotlin.fir.builder.addDestructuringStatements
+import org.jetbrains.kotlin.fir.builder.addDestructuringVariables
 import org.jetbrains.kotlin.fir.declarations.FirVariable
 import org.jetbrains.kotlin.fir.expressions.FirAnnotation
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -80,7 +80,7 @@ fun MutableList<FirStatement>.addDestructuringStatements(
     localEntries: Boolean,
 ) {
     with(DestructuringEntry) {
-        addDestructuringStatements(
+        addDestructuringVariables(
             moduleData,
             container,
             multiDeclaration.entries,

compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/PsiConversionUtils.kt

@@ -132,7 +132,7 @@ internal fun generateDestructuringBlock(
 ): FirBlock {
     return buildBlock {
         source = multiDeclaration.toKtPsiSourceElement()
-        statements.addDestructuringStatements(
+        statements.addDestructuringVariables(
             moduleData,
             multiDeclaration,
             container,
@@ -143,12 +143,15 @@ internal fun generateDestructuringBlock(
 }
 
 context(AbstractRawFirBuilder<*>, DestructuringContext<KtDestructuringDeclarationEntry>)
-internal fun MutableList<FirStatement>.addDestructuringStatements(
+internal fun MutableList<in FirVariable>.addDestructuringVariables(
     moduleData: FirModuleData,
     multiDeclaration: KtDestructuringDeclaration,
     container: FirVariable,
     tmpVariable: Boolean,
     localEntries: Boolean,
+    configure: (FirVariable) -> Unit = {}
 ) {
-    addDestructuringStatements(moduleData, container, multiDeclaration.entries, multiDeclaration.isVar, tmpVariable, localEntries)
+    this@addDestructuringVariables.addDestructuringVariables(
+        moduleData, container, multiDeclaration.entries, multiDeclaration.isVar, tmpVariable, localEntries, configure
+    )
 }

compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/PsiRawFirBuilder.kt

@@ -1299,19 +1299,17 @@ open class PsiRawFirBuilder(
                             ).apply {
                                 isDestructuringDeclarationContainerVariable = true
                             }
-                            val destructuringBlock = generateDestructuringBlock(
-                                baseModuleData,
+                            statements.add(destructuringContainerVar)
+
+                            statements.addDestructuringVariables(
+                                moduleData,
                                 declaration,
                                 destructuringContainerVar,
                                 tmpVariable = false,
                                 localEntries = false,
-                            ).apply {
-                                statements.forEach {
-                                    (it as FirProperty).destructuringDeclarationContainerVariable = destructuringContainerVar.symbol
-                                }
+                            ) {
+                                (it as FirProperty).destructuringDeclarationContainerVariable = destructuringContainerVar.symbol
                             }
-                            statements.add(destructuringContainerVar)
-                            statements.addAll(destructuringBlock.statements)
                         }
                         else -> {
                             statements.add(declaration.toFirStatement())
@@ -1835,7 +1833,7 @@ open class PsiRawFirBuilder(
                 isLambda = true
                 hasExplicitParameterList = expression.functionLiteral.arrow != null
 
-                val destructuringStatements = mutableListOf<FirStatement>()
+                val destructuringVariables = mutableListOf<FirStatement>()
                 for (valueParameter in literal.valueParameters) {
                     val multiDeclaration = valueParameter.destructuringDeclaration
                     valueParameters += if (multiDeclaration != null) {
@@ -1852,7 +1850,7 @@ open class PsiRawFirBuilder(
                             isNoinline = false
                             isVararg = false
                         }
-                        destructuringStatements.addDestructuringStatements(
+                        destructuringVariables.addDestructuringVariables(
                             baseModuleData,
                             multiDeclaration,
                             multiParameter,
@@ -1881,7 +1879,7 @@ open class PsiRawFirBuilder(
                         val errorExpression = buildErrorExpression(source, ConeSyntaxDiagnostic("Lambda has no body"))
                         FirSingleExpressionBlock(errorExpression.toReturn())
                     } else {
-                        val kind = runIf(destructuringStatements.isNotEmpty()) {
+                        val kind = runIf(destructuringVariables.isNotEmpty()) {
                             KtFakeSourceElementKind.LambdaDestructuringBlock
                         }
                         val bodyBlock = configureBlockWithoutBuilding(ktBody, kind).apply {
@@ -1905,11 +1903,11 @@ open class PsiRawFirBuilder(
                             }
                         }.build()
 
-                        if (destructuringStatements.isNotEmpty()) {
+                        if (destructuringVariables.isNotEmpty()) {
                             // Destructured variables must be in a separate block so that they can be shadowed.
                             buildBlock {
                                 source = bodyBlock.source?.realElement()
-                                statements.addAll(destructuringStatements)
+                                statements.addAll(destructuringVariables)
                                 statements.add(bodyBlock)
                             }
                         } else {
@@ -2739,7 +2737,7 @@ open class PsiRawFirBuilder(
                             extractedAnnotations = ktParameter.modifierList?.annotationEntries?.map { it.convert<FirAnnotation>() },
                         )
                         if (multiDeclaration != null) {
-                            blockBuilder.statements.addDestructuringStatements(
+                            blockBuilder.statements.addDestructuringVariables(
                                 baseModuleData,
                                 multiDeclaration = multiDeclaration,
                                 container = firLoopParameter,

compiler/fir/raw-fir/raw-fir.common/src/org/jetbrains/kotlin/fir/builder/Destructuring.kt

@@ -13,7 +13,6 @@ import org.jetbrains.kotlin.fir.declarations.FirDeclarationOrigin
 import org.jetbrains.kotlin.fir.declarations.FirVariable
 import org.jetbrains.kotlin.fir.declarations.builder.buildProperty
 import org.jetbrains.kotlin.fir.declarations.impl.FirDeclarationStatusImpl
-import org.jetbrains.kotlin.fir.expressions.FirStatement
 import org.jetbrains.kotlin.fir.symbols.FirBasedSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirPropertySymbol
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -27,13 +26,14 @@ interface DestructuringContext<T> {
 }
 
 context(AbstractRawFirBuilder<*>, DestructuringContext<T>)
-fun <T> MutableList<FirStatement>.addDestructuringStatements(
+fun <T> MutableList<in FirVariable>.addDestructuringVariables(
     moduleData: FirModuleData,
     container: FirVariable,
     entries: List<T>,
     isVar: Boolean,
     tmpVariable: Boolean,
     localEntries: Boolean,
+    configure: (FirVariable) -> Unit = {}
 ) {
     if (tmpVariable) {
         this += container
@@ -53,6 +53,6 @@ fun <T> MutableList<FirStatement>.addDestructuringStatements(
                 status = FirDeclarationStatusImpl(if (localEntries) Visibilities.Local else Visibilities.Public, Modality.FINAL)
                 entry.extractAnnotationsTo(this, context.containerSymbol)
             }
-        }
+        }.also(configure)
     }
 }