[FIR] Add contaning class lookup element for local FirRegular classes

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

@@ -524,6 +524,8 @@ class DeclarationsConverter(
                     }
                 }
             }
+        }.also {
+            it.initContainingClassForLocalAttr()
         }
     }
 

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

@@ -896,6 +896,8 @@ open class RawFirBuilder(
                         }
                     }
                 }
+            }.also {
+                it.initContainingClassForLocalAttr()
             }
         }
 

compiler/fir/raw-fir/psi2fir/testData/rawBuilder/declarations/initBlockWithDeclarations.txt

@@ -5,7 +5,7 @@ FILE: initBlockWithDeclarations.kt
         }
 
         init {
-            local final? class classInInit : R|kotlin/Any| {
+            local final? [ContainingClassKey=X] class classInInit : R|kotlin/Any| {
                 public? [ContainingClassKey=classInInit] constructor(): R|X.classInInit| {
                     super<R|kotlin/Any|>()
                 }
@@ -27,7 +27,7 @@ FILE: initBlockWithDeclarations.kt
         }
 
         init {
-            local final? class classInInit : R|kotlin/Any| {
+            local final? [ContainingClassKey=<no name provided>] class classInInit : R|kotlin/Any| {
                 public? [ContainingClassKey=classInInit] constructor(): R|<no name provided>.classInInit| {
                     super<R|kotlin/Any|>()
                 }

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

@@ -1152,6 +1152,15 @@ abstract class BaseFirBuilder<T>(val baseSession: FirSession, val context: Conte
         }
     }
 
+    protected fun FirRegularClass.initContainingClassForLocalAttr() {
+        if (isLocal) {
+            val currentDispatchReceiverType = currentDispatchReceiverType()
+            if (currentDispatchReceiverType != null) {
+                containingClassForLocalAttr = currentDispatchReceiverType.lookupTag
+            }
+        }
+    }
+
     protected fun FirCallableDeclaration<*>.initContainingClassAttr() {
         val currentDispatchReceiverType = currentDispatchReceiverType() ?: return
         containingClassAttr = currentDispatchReceiverType.lookupTag

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

@@ -32,9 +32,12 @@ fun FirCallableDeclaration<*>.containingClass(): ConeClassLikeLookupTag? {
 fun FirCallableMemberDeclaration<*>.containingClass(): ConeClassLikeLookupTag? {
     return (containingClassAttr ?: dispatchReceiverClassOrNull())
 }
+fun FirRegularClass.containingClassForLocal(): ConeClassLikeLookupTag? =
+    if (isLocal) containingClassForLocalAttr else null
 
 private object ContainingClassKey : FirDeclarationDataKey()
 var FirCallableDeclaration<*>.containingClassAttr: ConeClassLikeLookupTag? by FirDeclarationDataRegistry.data(ContainingClassKey)
+var FirRegularClass.containingClassForLocalAttr: ConeClassLikeLookupTag? by FirDeclarationDataRegistry.data(ContainingClassKey)
 
 val FirCallableDeclaration<*>.isIntersectionOverride get() = origin == FirDeclarationOrigin.IntersectionOverride
 val FirCallableDeclaration<*>.isSubstitutionOverride get() = origin == FirDeclarationOrigin.SubstitutionOverride