FIR2IR: fix top-level parent settings thus fixing Cli.testFirHello

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt

@@ -17,6 +17,7 @@ import org.jetbrains.kotlin.fir.descriptors.FirModuleDescriptor
 import org.jetbrains.kotlin.fir.descriptors.FirPackageFragmentDescriptor
 import org.jetbrains.kotlin.fir.expressions.FirVariable
 import org.jetbrains.kotlin.fir.render
+import org.jetbrains.kotlin.fir.resolve.FirProvider
 import org.jetbrains.kotlin.fir.resolve.FirSymbolProvider
 import org.jetbrains.kotlin.fir.resolve.getOrPut
 import org.jetbrains.kotlin.fir.service
@@ -44,8 +45,12 @@ class Fir2IrDeclarationStorage(
 ) {
     private val firSymbolProvider = session.service<FirSymbolProvider>()
 
+    private val firProvider = session.service<FirProvider>()
+
     private val fragmentCache = mutableMapOf<FqName, IrExternalPackageFragment>()
 
+    private val fileCache = mutableMapOf<FirFile, IrFile>()
+
     private val classCache = mutableMapOf<FirRegularClass, IrClass>()
 
     private val typeParameterCache = mutableMapOf<FirTypeParameter, IrTypeParameter>()
@@ -62,6 +67,10 @@ class Fir2IrDeclarationStorage(
 
     private val unitType = session.builtinTypes.unitType.toIrType(session, this)
 
+    fun registerFile(firFile: FirFile, irFile: IrFile) {
+        fileCache[firFile] = irFile
+    }
+
     fun enterScope(descriptor: DeclarationDescriptor) {
         irSymbolTable.enterScope(descriptor)
         if (descriptor is WrappedSimpleFunctionDescriptor ||
@@ -219,8 +228,13 @@ class Fir2IrDeclarationStorage(
                 null
             }
         } else {
-            val packageFqName = callableId.packageName
+            val containerFile = firProvider.getFirCallableContainerFile(firBasedSymbol)
-            getIrExternalPackageFragment(packageFqName)
+            if (containerFile != null) {
+                fileCache[containerFile]
+            } else {
+                val packageFqName = callableId.packageName
+                getIrExternalPackageFragment(packageFqName)
+            }
         }
     }
 

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt

@@ -27,7 +27,6 @@ import org.jetbrains.kotlin.fir.scopes.impl.FirClassSubstitutionScope
 import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.fir.visitors.FirDefaultVisitor
-import org.jetbrains.kotlin.fir.visitors.FirVisitor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.builders.*
@@ -142,6 +141,7 @@ class Fir2IrVisitor(
             sourceManager.getOrCreateFileEntry(file.psi as KtFile),
             moduleDescriptor.findPackageFragmentForFile(file)
         ).withParent {
+            declarationStorage.registerFile(file, this)
             file.declarations.forEach {
                 val irDeclaration = it.toIrDeclaration() ?: return@forEach
                 declarations += irDeclaration