Minor. FIR: Simplify createFunctionalType

^KT-32725 In Progress

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ResolveUtils.kt

@@ -6,7 +6,8 @@
 package org.jetbrains.kotlin.fir.resolve
 
 import org.jetbrains.kotlin.descriptors.ClassKind
-import org.jetbrains.kotlin.fir.*
+import org.jetbrains.kotlin.fir.FirSession
+import org.jetbrains.kotlin.fir.componentArrayAccessor
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccess
 import org.jetbrains.kotlin.fir.expressions.FirResolvable
@@ -14,9 +15,11 @@ import org.jetbrains.kotlin.fir.expressions.FirResolvedQualifier
 import org.jetbrains.kotlin.fir.references.FirErrorNamedReference
 import org.jetbrains.kotlin.fir.references.FirResolvedCallableReference
 import org.jetbrains.kotlin.fir.references.FirThisReference
+import org.jetbrains.kotlin.fir.render
 import org.jetbrains.kotlin.fir.resolve.calls.FirNamedReferenceWithCandidate
 import org.jetbrains.kotlin.fir.resolve.substitution.AbstractConeSubstitutor
 import org.jetbrains.kotlin.fir.resolve.transformers.body.resolve.resultType
+import org.jetbrains.kotlin.fir.resolvedTypeFromPrototype
 import org.jetbrains.kotlin.fir.scopes.impl.FirMemberScopeProvider
 import org.jetbrains.kotlin.fir.scopes.impl.withReplacedConeType
 import org.jetbrains.kotlin.fir.symbols.*
@@ -205,13 +208,12 @@ fun FirFunction<*>.constructFunctionalTypeRef(session: FirSession): FirResolvedT
     }
     val rawReturnType = (this as FirTypedDeclaration).returnTypeRef.coneTypeUnsafe<ConeKotlinType>()
 
-    val functionalType = createFunctionalType(session, parameters, receiverTypeRef?.coneTypeUnsafe(), rawReturnType)
+    val functionalType = createFunctionalType(parameters, receiverTypeRef?.coneTypeUnsafe(), rawReturnType)
 
     return FirResolvedTypeRefImpl(psi, functionalType)
 }
 
 fun createFunctionalType(
-    session: FirSession,
     parameters: List<ConeKotlinType>,
     receiverType: ConeKotlinType?,
     rawReturnType: ConeKotlinType
@@ -219,15 +221,14 @@ fun createFunctionalType(
     val receiverAndParameterTypes = listOfNotNull(receiverType) + parameters + listOf(rawReturnType)
 
     val functionalTypeId = StandardClassIds.byName("Function${receiverAndParameterTypes.size - 1}")
-    val functionalType = functionalTypeId(session.firSymbolProvider).constructType(receiverAndParameterTypes.toTypedArray(), isNullable = false)
+    return ConeClassTypeImpl(ConeClassLikeLookupTagImpl(functionalTypeId), receiverAndParameterTypes.toTypedArray(), isNullable = false)
-    return functionalType
 }
 
 fun BodyResolveComponents.typeForQualifier(resolvedQualifier: FirResolvedQualifier): FirTypeRef {
     val classId = resolvedQualifier.classId
     val resultType = resolvedQualifier.resultType
     if (classId != null) {
-        val classSymbol: FirClassLikeSymbol<*> = symbolProvider.getClassLikeSymbolByFqName(classId)!!
+        val classSymbol = symbolProvider.getClassLikeSymbolByFqName(classId)!!
         val declaration = classSymbol.phasedFir
         if (declaration is FirClass) {
             if (declaration.classKind == ClassKind.OBJECT) {
@@ -311,8 +312,10 @@ private fun BodyResolveComponents.typeFromSymbol(symbol: AbstractFirBasedSymbol<
                     "no enum item supertype"
                 )
             } else
-                FirResolvedTypeRefImpl(null, symbol.constructType(emptyArray(), isNullable = false))
+                FirResolvedTypeRefImpl(
+                    null, symbol.constructType(emptyArray(), isNullable = false)
+                )
         }
         else -> error("WTF ! $symbol")
     }
-}
+}

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/SamResolution.kt

@@ -191,7 +191,7 @@ class FirSamResolverImpl(
             val abstractMethod = firRegularClass.getSingleAbstractMethodOrNull(firSession, scopeSession) ?: return@getOrPut NULL_STUB
             // TODO: val shouldConvertFirstParameterToDescriptor = samWithReceiverResolvers.any { it.shouldConvertFirstSamParameterToReceiver(abstractMethod) }
 
-            abstractMethod.getFunctionTypeForAbstractMethod(firSession)
+            abstractMethod.getFunctionTypeForAbstractMethod()
         } as? ConeKotlinType
     }
 
@@ -292,14 +292,13 @@ private fun FirRegularClass.hasMoreThenOneAbstractFunctionOrHasAbstractProperty(
     return false
 }
 
-private fun FirSimpleFunction.getFunctionTypeForAbstractMethod(session: FirSession): ConeLookupTagBasedType {
+private fun FirSimpleFunction.getFunctionTypeForAbstractMethod(): ConeLookupTagBasedType {
     val parameterTypes = valueParameters.map {
         it.returnTypeRef.coneTypeSafe<ConeKotlinType>() ?: ConeKotlinErrorType("No type for parameter $it")
     }
 
     return createFunctionalType(
-        session, parameterTypes,
+        parameterTypes, receiverType = null,
-        receiverType = null,
         rawReturnType = returnTypeRef.coneTypeSafe() ?: ConeKotlinErrorType("No type for return type of $this")
     )
 }