[FIR] refactoring, use data class instead of a Pair in FirTypeResolver.resolveType

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

@@ -23,7 +23,12 @@ abstract class FirTypeResolver : FirSessionComponent {
         // Note: sometimes we don't have useSiteFile in IDE context
         useSiteFile: FirFile?,
         supertypeSupplier: SupertypeSupplier
-    ): Pair<ConeKotlinType, ConeDiagnostic?>
+    ): FirTypeResolutionResult
 }
 
+data class FirTypeResolutionResult(
+    val type: ConeKotlinType,
+    val diagnostic: ConeDiagnostic?,
+)
+
 val FirSession.typeResolver: FirTypeResolver by FirSession.sessionComponentAccessor()

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/providers/impl/FirTypeResolverImpl.kt

@@ -449,7 +449,7 @@ class FirTypeResolverImpl(private val session: FirSession) : FirTypeResolver() {
     private fun createFunctionType(
         typeRef: FirFunctionTypeRef,
         containerDeclaration: FirDeclaration? = null
-    ): Pair<ConeClassLikeTypeImpl, ConeDiagnostic?> {
+    ): FirTypeResolutionResult {
         val parameters =
             typeRef.contextReceiverTypeRefs.map { it.coneType } +
                     listOfNotNull(typeRef.receiverTypeRef?.coneType) +
@@ -482,12 +482,15 @@ class FirTypeResolverImpl(private val session: FirSession) : FirTypeResolver() {
             containerDeclaration,
             shouldExpandTypeAliases = true
         )
-        return ConeClassLikeTypeImpl(
-            classId.toLookupTag(),
-            parameters.toTypedArray(),
-            typeRef.isMarkedNullable,
-            attributes
-        ) to diagnostic
+        return FirTypeResolutionResult(
+            ConeClassLikeTypeImpl(
+                classId.toLookupTag(),
+                parameters.toTypedArray(),
+                typeRef.isMarkedNullable,
+                attributes
+            ),
+            diagnostic
+        )
     }
 
     override fun resolveType(
@@ -498,28 +501,29 @@ class FirTypeResolverImpl(private val session: FirSession) : FirTypeResolver() {
         resolveDeprecations: Boolean,
         useSiteFile: FirFile?,
         supertypeSupplier: SupertypeSupplier
-    ): Pair<ConeKotlinType, ConeDiagnostic?> {
+    ): FirTypeResolutionResult {
         return when (typeRef) {
             is FirResolvedTypeRef -> error("Do not resolve, resolved type-refs")
             is FirUserTypeRef -> {
                 val result = resolveUserTypeToSymbol(typeRef, scopeClassDeclaration, useSiteFile, supertypeSupplier, resolveDeprecations)
-                resolveUserType(
+                val resolvedType = resolveUserType(
                     typeRef,
                     result,
                     areBareTypesAllowed,
                     scopeClassDeclaration.topContainer ?: scopeClassDeclaration.containingDeclarations.lastOrNull(),
                     scopeClassDeclaration.containerDeclaration,
                     isOperandOfIsOperator,
-                ) to (result as? TypeResolutionResult.Resolved)?.typeCandidate?.diagnostic
+                )
+                FirTypeResolutionResult(resolvedType, (result as? TypeResolutionResult.Resolved)?.typeCandidate?.diagnostic)
             }
             is FirFunctionTypeRef -> createFunctionType(typeRef, scopeClassDeclaration.containerDeclaration)
-            is FirDynamicTypeRef -> ConeDynamicType.create(session) to null
+            is FirDynamicTypeRef -> FirTypeResolutionResult(ConeDynamicType.create(session), diagnostic = null)
             is FirIntersectionTypeRef -> {
                 val leftType = typeRef.leftType.coneType
                 if (leftType is ConeTypeParameterType) {
-                    ConeDefinitelyNotNullType(leftType) to null
+                    FirTypeResolutionResult(ConeDefinitelyNotNullType(leftType), diagnostic = null)
                 } else {
-                    ConeErrorType(ConeForbiddenIntersection) to null
+                    FirTypeResolutionResult(ConeErrorType(ConeForbiddenIntersection), diagnostic = null)
                 }
             }
             else -> error(typeRef.render())

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/FirSpecificTypeResolverTransformer.kt

@@ -15,6 +15,7 @@ import org.jetbrains.kotlin.fir.diagnostics.ConeDiagnostic
 import org.jetbrains.kotlin.fir.diagnostics.ConeSimpleDiagnostic
 import org.jetbrains.kotlin.fir.diagnostics.ConeUnexpectedTypeArgumentsError
 import org.jetbrains.kotlin.fir.expressions.FirStatement
+import org.jetbrains.kotlin.fir.resolve.FirTypeResolutionResult
 import org.jetbrains.kotlin.fir.resolve.SupertypeSupplier
 import org.jetbrains.kotlin.fir.resolve.diagnostics.ConeUnsupportedDefaultValueInFunctionType
 import org.jetbrains.kotlin.fir.resolve.transformers.body.resolve.resultType
@@ -95,8 +96,8 @@ class FirSpecificTypeResolverTransformer(
         val scopeOwnerLookupNames = data.scopes.flatMap { it.scopeOwnerLookupNames }
         session.lookupTracker?.recordTypeLookup(functionTypeRef, scopeOwnerLookupNames, currentFile?.source)
         val resolvedTypeWithDiagnostic = resolveType(functionTypeRef, data)
-        val resolvedType = resolvedTypeWithDiagnostic.first.takeIfAcceptable()
-        val diagnostic = resolvedTypeWithDiagnostic.second
+        val resolvedType = resolvedTypeWithDiagnostic.type.takeIfAcceptable()
+        val diagnostic = resolvedTypeWithDiagnostic.diagnostic
         return if (resolvedType != null && resolvedType !is ConeErrorType && diagnostic == null) {
             buildResolvedTypeRef {
                 source = functionTypeRef.source
@@ -120,7 +121,7 @@ class FirSpecificTypeResolverTransformer(
     private fun FirSpecificTypeResolverTransformer.resolveType(
         typeRef: FirTypeRef,
         scopeClassDeclaration: ScopeClassDeclaration,
-    ): Pair<ConeKotlinType, ConeDiagnostic?> {
+    ): FirTypeResolutionResult {
         return typeResolver.resolveType(
             typeRef,
             scopeClassDeclaration,