Remove all type system dependent methods from TypeCheckerState

core/compiler.common/src/org/jetbrains/kotlin/types/AbstractTypeChecker.kt

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.types
 
+import org.jetbrains.kotlin.descriptors.containerRelation
 import org.jetbrains.kotlin.types.TypeCheckerState.LowerCapturedTypePolicy.*
 import org.jetbrains.kotlin.types.TypeCheckerState.SupertypesPolicy
 import org.jetbrains.kotlin.types.model.*
@@ -27,7 +28,7 @@ abstract class TypeCheckerState {
 
     abstract val typeSystemContext: TypeSystemContext
 
-    abstract fun substitutionSupertypePolicy(type: SimpleTypeMarker): SupertypesPolicy
+    abstract val allowedTypeVariable: Boolean
 
     @OptIn(TypeRefinement::class)
     fun refineType(type: KotlinTypeMarker): KotlinTypeMarker {
@@ -157,10 +158,9 @@ abstract class TypeCheckerState {
         abstract class DoCustomTransform : SupertypesPolicy()
     }
 
-    abstract val KotlinTypeMarker.isAllowedTypeVariable: Boolean
-
-    @JvmName("isAllowedTypeVariableBridge")
-    fun isAllowedTypeVariable(type: KotlinTypeMarker): Boolean = type.isAllowedTypeVariable
+    fun isAllowedTypeVariable(type: KotlinTypeMarker): Boolean {
+        return allowedTypeVariable && with(typeSystemContext) { type.isTypeVariableType() }
+    }
 }
 
 object AbstractTypeChecker {
@@ -596,7 +596,7 @@ object AbstractTypeChecker {
                     SupertypesPolicy.LowerIfFlexible
                 }
                 else -> {
-                    state.substitutionSupertypePolicy(current)
+                    state.typeSystemContext.substitutionSupertypePolicy(current)
                 }
             }
         }

core/compiler.common/src/org/jetbrains/kotlin/types/model/TypeSystemContext.kt

@@ -461,6 +461,10 @@ interface TypeSystemContext : TypeSystemOptimizationContext {
     fun SimpleTypeMarker.isPrimitiveType(): Boolean
 
     fun KotlinTypeMarker.getAnnotations(): List<AnnotationMarker>
+
+    fun substitutionSupertypePolicy(type: SimpleTypeMarker): TypeCheckerState.SupertypesPolicy
+
+    fun KotlinTypeMarker.isTypeVariableType(): Boolean
 }
 
 enum class CaptureStatus {

core/descriptors/src/org/jetbrains/kotlin/resolve/OverridingUtilTypeSystemContext.kt

@@ -32,7 +32,6 @@ class OverridingUtilTypeSystemContext(
         return ClassicTypeCheckerState(
             errorTypesEqualToAnything,
             stubTypesEqualToAnything,
-            allowedTypeVariable = true,
             kotlinTypeRefiner,
             typeSystemContext = this
         )

core/descriptors/src/org/jetbrains/kotlin/types/checker/ClassicTypeCheckerState.kt

@@ -23,7 +23,6 @@ import org.jetbrains.kotlin.types.model.SimpleTypeMarker
 open class ClassicTypeCheckerState(
     val errorTypeEqualsToAnything: Boolean,
     val stubTypeEqualsToAnything: Boolean = true,
-    val allowedTypeVariable: Boolean = true,
     override val kotlinTypeRefiner: KotlinTypeRefiner = KotlinTypeRefiner.Default,
     override val kotlinTypePreparator: KotlinTypePreparator = KotlinTypePreparator.Default,
     override val typeSystemContext: ClassicTypeSystemContext = SimpleClassicTypeSystemContext
@@ -34,29 +33,6 @@ open class ClassicTypeCheckerState(
     override val isStubTypeEqualsToAnything: Boolean
         get() = stubTypeEqualsToAnything
 
-    override fun substitutionSupertypePolicy(type: SimpleTypeMarker): SupertypesPolicy.DoCustomTransform {
-        return typeSystemContext.classicSubstitutionSupertypePolicy(type)
-    }
-
-    override val KotlinTypeMarker.isAllowedTypeVariable: Boolean get() = this is UnwrappedType && allowedTypeVariable && constructor is NewTypeVariableConstructor
-
-    companion object {
-        fun ClassicTypeSystemContext.classicSubstitutionSupertypePolicy(type: SimpleTypeMarker): SupertypesPolicy.DoCustomTransform {
-            require(type is SimpleType, type::errorMessage)
-            val substitutor = TypeConstructorSubstitution.create(type).buildSubstitutor()
-
-            return object : SupertypesPolicy.DoCustomTransform() {
-                override fun transformType(state: TypeCheckerState, type: KotlinTypeMarker): SimpleTypeMarker {
-                    return substitutor.safeSubstitute(
-                        type.lowerBoundIfFlexible() as KotlinType,
-                        Variance.INVARIANT
-                    ).asSimpleType()!!
-                }
-            }
-        }
-    }
-}
-
-private fun Any.errorMessage(): String {
-    return "ClassicTypeCheckerContext couldn't handle ${this::class} $this"
+    override val allowedTypeVariable: Boolean
+        get() = true
 }

core/descriptors/src/org/jetbrains/kotlin/types/checker/ClassicTypeSystemContext.kt

@@ -788,6 +788,24 @@ interface ClassicTypeSystemContext : TypeSystemInferenceExtensionContext, TypeSy
         } else {
             createFlexibleType(this, this.withNullability(true))
         }
+
+    override fun substitutionSupertypePolicy(type: SimpleTypeMarker): TypeCheckerState.SupertypesPolicy {
+        require(type is SimpleType, type::errorMessage)
+        val substitutor = TypeConstructorSubstitution.create(type).buildSubstitutor()
+
+        return object : TypeCheckerState.SupertypesPolicy.DoCustomTransform() {
+            override fun transformType(state: TypeCheckerState, type: KotlinTypeMarker): SimpleTypeMarker {
+                return substitutor.safeSubstitute(
+                    type.lowerBoundIfFlexible() as KotlinType,
+                    Variance.INVARIANT
+                ).asSimpleType()!!
+            }
+        }
+    }
+
+    override fun KotlinTypeMarker.isTypeVariableType(): Boolean {
+        return this is UnwrappedType && constructor is NewTypeVariableConstructor
+    }
 }
 
 fun TypeVariance.convertVariance(): Variance {