Pull isNullableType and related extensions up into TypeSystemContext

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ConeInferenceContext.kt

@@ -256,21 +256,6 @@ interface ConeInferenceContext : TypeSystemInferenceExtensionContext,
         return this.constructor.projection
     }
 
-    override fun KotlinTypeMarker.isNullableType(): Boolean {
-        require(this is ConeKotlinType)
-        if (this.isMarkedNullable)
-            return true
-
-        if (this is ConeFlexibleType && this.upperBound.isNullableType())
-            return true
-
-        if (this is ConeTypeParameterType /* || is TypeVariable */)
-            return hasNullableSuperType(type)
-
-        // TODO: Intersection types
-        return false
-    }
-
     override fun DefinitelyNotNullTypeMarker.original(): SimpleTypeMarker {
         require(this is ConeDefinitelyNotNullType)
         return this.original()

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/InferenceUtil.kt

@@ -6,19 +6,26 @@
 package org.jetbrains.kotlin.fir.resolve.calls
 
 import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.resolve.*
+import org.jetbrains.kotlin.fir.resolve.ScopeSession
+import org.jetbrains.kotlin.fir.resolve.toSymbol
 import org.jetbrains.kotlin.fir.resolve.transformers.ReturnTypeCalculator
-import org.jetbrains.kotlin.fir.symbols.*
+import org.jetbrains.kotlin.fir.symbols.ConeClassifierLookupTag
+import org.jetbrains.kotlin.fir.symbols.ConeSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirTypeParameterSymbol
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.resolve.calls.inference.components.*
+import org.jetbrains.kotlin.resolve.calls.inference.components.ConstraintIncorporator
+import org.jetbrains.kotlin.resolve.calls.inference.components.ConstraintInjector
+import org.jetbrains.kotlin.resolve.calls.inference.components.ResultTypeResolver
+import org.jetbrains.kotlin.resolve.calls.inference.components.TrivialConstraintTypeInferenceOracle
 import org.jetbrains.kotlin.resolve.calls.inference.model.NewConstraintSystemImpl
 import org.jetbrains.kotlin.types.AbstractTypeApproximator
-import org.jetbrains.kotlin.types.model.*
+import org.jetbrains.kotlin.types.model.SimpleTypeMarker
+import org.jetbrains.kotlin.types.model.TypeSystemInferenceExtensionContextDelegate
+import org.jetbrains.kotlin.types.model.TypeVariableMarker
+import org.jetbrains.kotlin.types.model.TypeVariableTypeConstructorMarker
 
-
-fun ConeInferenceContext.hasNullableSuperType(type: ConeKotlinType): Boolean {
+fun ConeTypeContext.hasNullableSuperType(type: ConeKotlinType): Boolean {
     if (type is ConeClassLikeType) return false
 
     if (type !is ConeLookupTagBasedType) return false // TODO?

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.fir.declarations.expandedConeType
 import org.jetbrains.kotlin.fir.declarations.superConeTypes
 import org.jetbrains.kotlin.fir.resolve.*
 import org.jetbrains.kotlin.fir.resolve.calls.ConeTypeVariableTypeConstructor
+import org.jetbrains.kotlin.fir.resolve.calls.hasNullableSuperType
 import org.jetbrains.kotlin.fir.resolve.substitution.ConeSubstitutor
 import org.jetbrains.kotlin.fir.resolve.substitution.ConeSubstitutorByMap
 import org.jetbrains.kotlin.fir.resolve.transformers.firUnsafe
@@ -28,7 +29,6 @@ import org.jetbrains.kotlin.types.AbstractTypeCheckerContext
 import org.jetbrains.kotlin.types.checker.convertVariance
 import org.jetbrains.kotlin.types.model.*
 
-
 class ErrorTypeConstructor(reason: String) : TypeConstructorMarker
 
 interface ConeTypeContext : TypeSystemContext, TypeSystemOptimizationContext {
@@ -408,6 +408,21 @@ interface ConeTypeContext : TypeSystemContext, TypeSystemOptimizationContext {
             else -> type
         }
     }
+
+    override fun KotlinTypeMarker.isNullableType(): Boolean {
+        require(this is ConeKotlinType)
+        if (this.isMarkedNullable)
+            return true
+
+        if (this is ConeFlexibleType && this.upperBound.isNullableType())
+            return true
+
+        if (this is ConeTypeParameterType /* || is TypeVariable */)
+            return hasNullableSuperType(type)
+
+        // TODO: Intersection types
+        return false
+    }
 }
 
 class ConeTypeCheckerContext(override val isErrorTypeEqualsToAnything: Boolean, override val session: FirSession) :

core/type-system/src/org/jetbrains/kotlin/types/model/TypeSystemContext.kt

@@ -127,12 +127,6 @@ interface TypeSystemInferenceExtensionContext : TypeSystemContext, TypeSystemBui
     fun CapturedTypeMarker.typeConstructorProjection(): TypeArgumentMarker
     fun CapturedTypeMarker.captureStatus(): CaptureStatus
 
-    fun KotlinTypeMarker.isNullableType(): Boolean
-
-    fun KotlinTypeMarker.isNullableAny() = this.typeConstructor().isAnyConstructor() && this.isNullableType()
-    fun KotlinTypeMarker.isNothing() = this.typeConstructor().isNothingConstructor() && !this.isNullableType()
-    fun KotlinTypeMarker.isNullableNothing() = this.typeConstructor().isNothingConstructor() && this.isNullableType()
-
     fun DefinitelyNotNullTypeMarker.original(): SimpleTypeMarker
 
     fun typeSubstitutorByTypeConstructor(map: Map<TypeConstructorMarker, KotlinTypeMarker>): TypeSubstitutorMarker
@@ -217,6 +211,12 @@ interface TypeSystemContext : TypeSystemOptimizationContext {
     fun KotlinTypeMarker.typeConstructor(): TypeConstructorMarker =
         (asSimpleType() ?: lowerBoundIfFlexible()).typeConstructor()
 
+    fun KotlinTypeMarker.isNullableType(): Boolean
+
+    fun KotlinTypeMarker.isNullableAny() = this.typeConstructor().isAnyConstructor() && this.isNullableType()
+    fun KotlinTypeMarker.isNothing() = this.typeConstructor().isNothingConstructor() && !this.isNullableType()
+    fun KotlinTypeMarker.isNullableNothing() = this.typeConstructor().isNothingConstructor() && this.isNullableType()
+
     fun SimpleTypeMarker.isClassType(): Boolean = typeConstructor().isClassTypeConstructor()
 
     fun SimpleTypeMarker.fastCorrespondingSupertypes(constructor: TypeConstructorMarker): List<SimpleTypeMarker>? = null