Fix incorrect handling of @NotNull type parameters

^KT-36770 In progress
^KT-40114 Relates
^KT-28785 Relates

core/descriptors.jvm/src/org/jetbrains/kotlin/load/java/lazy/context.kt

@@ -29,7 +29,6 @@ import org.jetbrains.kotlin.load.java.JavaClassFinder
 import org.jetbrains.kotlin.load.java.JavaClassesTracker
 import org.jetbrains.kotlin.load.java.components.JavaPropertyInitializerEvaluator
 import org.jetbrains.kotlin.load.java.components.JavaResolverCache
-import org.jetbrains.kotlin.resolve.sam.SamConversionResolver
 import org.jetbrains.kotlin.load.java.components.SignaturePropagator
 import org.jetbrains.kotlin.load.java.lazy.types.JavaTypeResolver
 import org.jetbrains.kotlin.load.java.sources.JavaSourceElementFactory
@@ -40,6 +39,7 @@ import org.jetbrains.kotlin.load.java.typeEnhancement.SignatureEnhancement
 import org.jetbrains.kotlin.load.kotlin.DeserializedDescriptorResolver
 import org.jetbrains.kotlin.load.kotlin.KotlinClassFinder
 import org.jetbrains.kotlin.load.kotlin.PackagePartProvider
+import org.jetbrains.kotlin.resolve.sam.SamConversionResolver
 import org.jetbrains.kotlin.serialization.deserialization.ErrorReporter
 import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.types.checker.NewKotlinTypeChecker
@@ -82,16 +82,24 @@ class JavaResolverComponents(
 
 interface JavaResolverSettings {
     val isReleaseCoroutines: Boolean
+    val correctNullabilityForNotNullTypeParameter: Boolean
 
     object Default : JavaResolverSettings {
         override val isReleaseCoroutines: Boolean
             get() = false
+
+        override val correctNullabilityForNotNullTypeParameter: Boolean
+            get() = false
     }
 
     companion object {
-        fun create(isReleaseCoroutines: Boolean): JavaResolverSettings =
+        fun create(
+            isReleaseCoroutines: Boolean,
+            correctNullabilityForNotNullTypeParameter: Boolean
+        ): JavaResolverSettings =
             object : JavaResolverSettings {
                 override val isReleaseCoroutines get() = isReleaseCoroutines
+                override val correctNullabilityForNotNullTypeParameter get() = correctNullabilityForNotNullTypeParameter
             }
     }
 }

core/descriptors.jvm/src/org/jetbrains/kotlin/load/java/typeEnhancement/typeEnhancement.kt

@@ -24,6 +24,7 @@ import org.jetbrains.kotlin.descriptors.annotations.AnnotationDescriptor
 import org.jetbrains.kotlin.descriptors.annotations.Annotations
 import org.jetbrains.kotlin.descriptors.annotations.CompositeAnnotations
 import org.jetbrains.kotlin.load.java.JvmAnnotationNames
+import org.jetbrains.kotlin.load.java.lazy.JavaResolverSettings
 import org.jetbrains.kotlin.load.java.lazy.types.RawTypeImpl
 import org.jetbrains.kotlin.load.java.typeEnhancement.MutabilityQualifier.MUTABLE
 import org.jetbrains.kotlin.load.java.typeEnhancement.MutabilityQualifier.READ_ONLY
@@ -51,7 +52,7 @@ enum class TypeComponentPosition {
     INFLEXIBLE
 }
 
-class JavaTypeEnhancement {
+class JavaTypeEnhancement(private val javaResolverSettings: JavaResolverSettings) {
 
     private open class Result(open val type: KotlinType, val subtreeSize: Int, val wereChanges: Boolean) {
         val typeIfChanged: KotlinType? get() = type.takeIf { wereChanges }
@@ -144,12 +145,18 @@ class JavaTypeEnhancement {
             enhancedNullability
         )
 
-        val enhancement = if (effectiveQualifiers.isNotNullTypeParameter) NotNullTypeParameter(enhancedType) else enhancedType
+        val enhancement = if (effectiveQualifiers.isNotNullTypeParameter) notNullTypeParameter(enhancedType) else enhancedType
         val nullabilityForWarning = enhancedNullabilityAnnotations != null && effectiveQualifiers.isNullabilityQualifierForWarning
         val result = if (nullabilityForWarning) wrapEnhancement(enhancement) else enhancement
 
         return SimpleResult(result as SimpleType, subtreeSize, wereChanges = true)
     }
+
+    private fun notNullTypeParameter(enhancedType: SimpleType) =
+        if (javaResolverSettings.correctNullabilityForNotNullTypeParameter)
+            enhancedType.makeSimpleTypeDefinitelyNotNullOrNotNull(useCorrectedNullabilityForTypeParameters = true)
+        else
+            NotNullTypeParameter(enhancedType)
 }
 
 private fun List<Annotations>.compositeAnnotationsOrSingle() = when (size) {