FIR supertype resolve: generate error types for type parameters

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

@@ -11,10 +11,7 @@ import org.jetbrains.kotlin.fir.expressions.FirStatement
 import org.jetbrains.kotlin.fir.render
 import org.jetbrains.kotlin.fir.resolve.*
 import org.jetbrains.kotlin.fir.scopes.addImportingScopes
-import org.jetbrains.kotlin.fir.types.ConeClassLikeType
-import org.jetbrains.kotlin.fir.types.FirResolvedTypeRef
-import org.jetbrains.kotlin.fir.types.FirTypeRef
-import org.jetbrains.kotlin.fir.types.coneTypeSafe
+import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.fir.types.impl.FirErrorTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.CompositeTransformResult
 import org.jetbrains.kotlin.fir.visitors.compose
@@ -162,7 +159,14 @@ class FirSupertypeResolverTransformer : FirAbstractTreeTransformer(phase = FirRe
 
             val resultingTypeRefs = mutableListOf<FirTypeRef>()
             for (superTypeRef in resolvedTypesRefs) {
-                val resolvedType = superTypeRef.coneTypeSafe<ConeClassLikeType>() ?: continue
+                val coneType = (superTypeRef as FirResolvedTypeRef).type
+                if (coneType is ConeTypeParameterType) {
+                    resultingTypeRefs.add(
+                        FirErrorTypeRefImpl(superTypeRef.psi, "Type parameter cannot be a super-type: ${coneType.render()}")
+                    )
+                    continue
+                }
+                val resolvedType = coneType as ConeClassLikeType
                 val superTypeClassId = resolvedType.lookupTag.classId
 
                 if (superTypeClassId.outerClasses().any { it.areSupertypesComputing() }) {

compiler/fir/resolve/testData/resolve/typeParameterVsNested.kt

@@ -14,4 +14,6 @@ abstract class My<T : Some> {
     abstract val z: test.My.T
 
     class Some : T()
-}
+}
+
+abstract class Your<T : Some> : T

compiler/fir/resolve/testData/resolve/typeParameterVsNested.txt

@@ -24,7 +24,7 @@ FILE: typeParameterVsNested.kt
         public abstract val z: R|test/My.T|
             public get(): R|test/My.T|
 
-        public final class Some : R|test/My.T| {
+        public final class Some : R|class error: Type parameter cannot be a super-type: T| {
             public constructor(): R|test/My.Some| {
                 super<R|T|>()
             }
@@ -32,3 +32,9 @@ FILE: typeParameterVsNested.kt
         }
 
     }
+    public abstract class Your<T : R|test/Some|> : R|class error: Type parameter cannot be a super-type: T| {
+        public constructor<T : R|test/Some|>(): R|test/Your<T>| {
+            super<R|kotlin/Any|>()
+        }
+
+    }