Remove UnsafeVarianceTypeSubstitution

Looks like it's not really used for anything

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/JvmBuiltInsSettings.kt

@@ -137,7 +137,6 @@ open class JvmBuiltInsSettings(
                 setOwner(classDescriptor)
                 setDispatchReceiverParameter(classDescriptor.thisAsReceiverParameter)
                 setPreserveSourceElement()
-                setSubstitution(UnsafeVarianceTypeSubstitution(moduleDescriptor.builtIns))
 
                 val memberStatus = additionalMember.getJdkMethodStatus()
                 when (memberStatus) {

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/UnsafeVarianceTypeSubstitution.kt

@@ -1,102 +0,0 @@
-/*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.kotlin.load.kotlin
-
-import org.jetbrains.kotlin.builtins.KotlinBuiltIns
-import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
-import org.jetbrains.kotlin.descriptors.annotations.AnnotationsImpl
-import org.jetbrains.kotlin.descriptors.annotations.BuiltInAnnotationDescriptor
-import org.jetbrains.kotlin.descriptors.annotations.composeAnnotations
-import org.jetbrains.kotlin.types.*
-
-internal class UnsafeVarianceTypeSubstitution(builtIns: KotlinBuiltIns) : TypeSubstitution() {
-    private val unsafeVarianceAnnotations = AnnotationsImpl(listOf(
-            BuiltInAnnotationDescriptor(builtIns, KotlinBuiltIns.FQ_NAMES.unsafeVariance, emptyMap())
-    ))
-
-    override fun get(key: KotlinType) = null
-
-    override fun prepareTopLevelType(topLevelType: KotlinType, position: Variance): KotlinType {
-        val unsafeVariancePaths = mutableListOf<List<Int>>()
-        IndexedTypeHolder(topLevelType).checkTypePosition(
-                position,
-                { _, indexedTypeHolder, _ ->
-                    unsafeVariancePaths.add(indexedTypeHolder.argumentIndices)
-                },
-                customVariance = { null })
-
-        return topLevelType.unwrap().annotatePartsWithUnsafeVariance(unsafeVariancePaths)
-    }
-    private fun UnwrappedType.annotatePartsWithUnsafeVariance(unsafeVariancePaths: Collection<List<Int>>): UnwrappedType {
-        if (unsafeVariancePaths.isEmpty()) return this
-        return when (this) {
-            is FlexibleType ->
-                KotlinTypeFactory.flexibleType(
-                        lowerBound.annotatePartsWithUnsafeVariance(subPathsWithIndex(unsafeVariancePaths, 0)),
-                        upperBound.annotatePartsWithUnsafeVariance(subPathsWithIndex(unsafeVariancePaths, 1))
-                    ).inheritEnhancement(this)
-            is SimpleType -> annotatePartsWithUnsafeVariance(unsafeVariancePaths)
-        }
-    }
-
-    private fun SimpleType.annotatePartsWithUnsafeVariance(unsafeVariancePaths: Collection<List<Int>>): SimpleType {
-        if (unsafeVariancePaths.isEmpty()) return this
-
-        // if root is unsafe
-        if (emptyList<Int>() in unsafeVariancePaths) {
-            return replaceAnnotations(composeAnnotations(annotations, unsafeVarianceAnnotations))
-        }
-
-        return replace(newArguments = arguments.withIndex().map {
-                    val (index, argument) = it
-                    if (argument.isStarProjection) return@map argument
-            TypeProjectionImpl(
-                    argument.projectionKind,
-                    argument.type.unwrap().annotatePartsWithUnsafeVariance(subPathsWithIndex(unsafeVariancePaths, index)))
-                })
-    }
-
-    private fun subPathsWithIndex(paths: Collection<List<Int>>, index: Int) = paths.filter { it[0] == index }.map { it.subList(1, it.size) }
-
-    private class IndexedTypeHolder(
-            override val type: KotlinType,
-            val argumentIndices: List<Int> = emptyList()
-    ) : TypeHolder<IndexedTypeHolder> {
-        override val flexibleBounds: Pair<IndexedTypeHolder, IndexedTypeHolder>? get() =
-            if (type.isFlexible())
-                Pair(
-                        IndexedTypeHolder(type.lowerIfFlexible(), argumentIndices + 0),
-                        IndexedTypeHolder(type.upperIfFlexible(), argumentIndices + 1))
-            else null
-
-        override val arguments: List<TypeHolderArgument<IndexedTypeHolder>>
-            get() = type.arguments.withIndex().map { projectionWithIndex ->
-
-                val (index, projection) = projectionWithIndex
-                object : TypeHolderArgument<IndexedTypeHolder> {
-                    override val projection: TypeProjection
-                        get() = projection
-                    override val typeParameter: TypeParameterDescriptor?
-                        get() = type.constructor.parameters[index]
-                    override val holder: IndexedTypeHolder
-                        get() = IndexedTypeHolder(projection.type, argumentIndices + index)
-
-                }
-            }
-
-    }
-}

core/descriptors/src/org/jetbrains/kotlin/types/VarianceChecker.kt

@@ -24,7 +24,6 @@ import org.jetbrains.kotlin.utils.DO_NOTHING_3
 interface TypeHolder<out D : TypeHolder<D>> {
     val type: KotlinType
     val arguments: List<TypeHolderArgument<D>?>
-    val flexibleBounds: Pair<D, D>? get() = null
 }
 
 interface TypeHolderArgument<out D : TypeHolder<D>> {
@@ -34,20 +33,16 @@ interface TypeHolderArgument<out D : TypeHolder<D>> {
 }
 
 fun <D : TypeHolder<D>> D.checkTypePosition(
-        position: Variance,
-        reportError: (TypeParameterDescriptor, D, Variance) -> Unit = DO_NOTHING_3,
-        customVariance: (TypeParameterDescriptor) -> Variance? = { null }
+    position: Variance,
+    reportError: (TypeParameterDescriptor, D, Variance) -> Unit = DO_NOTHING_3,
+    customVariance: (TypeParameterDescriptor) -> Variance? = { null }
 ): Boolean {
-    flexibleBounds?.let {
-        return it.first.checkTypePosition(position, reportError, customVariance) and
-                    it.second.checkTypePosition(position, reportError, customVariance)
-    }
-
     val classifierDescriptor = type.constructor.declarationDescriptor
     if (classifierDescriptor is TypeParameterDescriptor) {
         val declarationVariance = customVariance(classifierDescriptor) ?: classifierDescriptor.variance
         if (!declarationVariance.allowsPosition(position)
-            && !type.annotations.hasAnnotation(org.jetbrains.kotlin.builtins.KotlinBuiltIns.FQ_NAMES.unsafeVariance)) {
+            && !type.annotations.hasAnnotation(org.jetbrains.kotlin.builtins.KotlinBuiltIns.FQ_NAMES.unsafeVariance)
+        ) {
             reportError(classifierDescriptor, this, position)
         }
         return declarationVariance.allowsPosition(position)