Introduce AbstractTypeMapper based on type markers

2020-09-22 18:20:57 +03:00
parent 7380abac13
commit 86d4d320c4
5 changed files with 208 additions and 51 deletions
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.types
+
+import org.jetbrains.kotlin.types.model.KotlinTypeMarker
+import org.jetbrains.kotlin.types.model.SimpleTypeMarker
+import org.jetbrains.kotlin.types.model.TypeConstructorMarker
+
+fun TypeSystemCommonBackendContext.computeExpandedTypeForInlineClass(inlineClassType: KotlinTypeMarker): KotlinTypeMarker? =
+    computeExpandedTypeInner(inlineClassType, hashSetOf())
+
+private fun TypeSystemCommonBackendContext.computeExpandedTypeInner(
+    kotlinType: KotlinTypeMarker, visitedClassifiers: HashSet<TypeConstructorMarker>
+): KotlinTypeMarker? {
+    val classifier = kotlinType.typeConstructor()
+    if (!visitedClassifiers.add(classifier)) return null
+
+    val typeParameter = classifier.getTypeParameterClassifier()
+
+    return when {
+        typeParameter != null ->
+            computeExpandedTypeInner(typeParameter.getRepresentativeUpperBound(), visitedClassifiers)
+                ?.let { expandedUpperBound ->
+                    if (expandedUpperBound.isNullableType() || !kotlinType.isMarkedNullable())
+                        expandedUpperBound
+                    else
+                        expandedUpperBound.makeNullable()
+                }
+
+        classifier.isInlineClass() -> {
+            // kotlinType is the boxed inline class type
+
+            val underlyingType = kotlinType.getSubstitutedUnderlyingType() ?: return null
+            val expandedUnderlyingType = computeExpandedTypeInner(underlyingType, visitedClassifiers) ?: return null
+            when {
+                !kotlinType.isNullableType() -> expandedUnderlyingType
+
+                // Here inline class type is nullable. Apply nullability to the expandedUnderlyingType.
+
+                // Nullable types become inline class boxes
+                expandedUnderlyingType.isNullableType() -> kotlinType
+
+                // Primitives become inline class boxes
+                expandedUnderlyingType is SimpleTypeMarker && expandedUnderlyingType.isPrimitiveType() -> kotlinType
+
+                // Non-null reference types become nullable reference types
+                else -> expandedUnderlyingType.makeNullable()
+            }
+        }
+
+        else -> kotlinType
+    }
+}