Substitute underlying constructor when substituting type alias constr…

…uctor

KT-17426 Constructor call of typealiased class gets suspicious type arguemnts

compiler/testData/ir/irText/classes/delegatingConstructorCallToTypeAliasConstructor.txt

@@ -18,14 +18,12 @@ FILE /delegatingConstructorCallToTypeAliasConstructor.kt
   CLASS CLASS C1
     CONSTRUCTOR public constructor C1()
       BLOCK_BODY
-        DELEGATING_CONSTRUCTOR_CALL 'constructor Cell(T)'
-          value: TYPE_OP type=T origin=IMPLICIT_CAST typeOperand=T
-            CONST String type=kotlin.String value='O'
+        DELEGATING_CONSTRUCTOR_CALL 'constructor Cell(String)'
+          value: CONST String type=kotlin.String value='O'
         INSTANCE_INITIALIZER_CALL classDescriptor='C1'
   CLASS CLASS C2
     CONSTRUCTOR public constructor C2()
       BLOCK_BODY
-        DELEGATING_CONSTRUCTOR_CALL 'constructor Cell(T)'
-          value: TYPE_OP type=T origin=IMPLICIT_CAST typeOperand=T
-            CONST String type=kotlin.String value='K'
+        DELEGATING_CONSTRUCTOR_CALL 'constructor Cell(String)'
+          value: CONST String type=kotlin.String value='K'
         INSTANCE_INITIALIZER_CALL classDescriptor='C2'

compiler/testData/ir/irText/regressions/typeAliasCtorForGenericClass.kt

@@ -0,0 +1,10 @@
+class A<Q>(val q: Q)
+
+typealias B<X> = A<X>
+
+typealias B2<T> = A<A<T>>
+
+fun bar() {
+    val b = B(2)
+    val b2 = B2(b)
+}

compiler/testData/ir/irText/regressions/typeAliasCtorForGenericClass.txt

@@ -0,0 +1,25 @@
+FILE /typeAliasCtorForGenericClass.kt
+  CLASS CLASS A
+    CONSTRUCTOR public constructor A<Q>(q: Q)
+      BLOCK_BODY
+        DELEGATING_CONSTRUCTOR_CALL 'constructor Any()'
+        INSTANCE_INITIALIZER_CALL classDescriptor='A'
+    PROPERTY public final val q: Q
+      FIELD PROPERTY_BACKING_FIELD public final val q: Q
+        EXPRESSION_BODY
+          GET_VAR 'value-parameter q: Q' type=Q origin=INITIALIZE_PROPERTY_FROM_PARAMETER
+      FUN DEFAULT_PROPERTY_ACCESSOR public final fun <get-q>(): Q
+        BLOCK_BODY
+          RETURN type=kotlin.Nothing from='<get-q>(): Q'
+            GET_FIELD 'q: Q' type=Q origin=null
+              receiver: GET_VAR '<receiver: A>' type=A<Q> origin=null
+  TYPEALIAS typealias B = A<X> type=A<X>
+  TYPEALIAS typealias B2 = A<A<T>> type=A<A<T>>
+  FUN public fun bar(): kotlin.Unit
+    BLOCK_BODY
+      VAR val b: B<kotlin.Int> /* = A<kotlin.Int> */
+        CALL 'constructor A(Int)' type=A<kotlin.Int> origin=null
+          q: CONST Int type=kotlin.Int value='2'
+      VAR val b2: B2<kotlin.Int> /* = A<A<kotlin.Int>> */
+        CALL 'constructor A(A<Int>)' type=A<A<kotlin.Int>> origin=null
+          q: GET_VAR 'b: B<Int> /* = A<Int> */' type=B<kotlin.Int> /* = A<kotlin.Int> */ origin=null

compiler/tests/org/jetbrains/kotlin/ir/IrTextTestCaseGenerated.java

@@ -901,6 +901,12 @@ public void testIntegerCoercionToT() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/ir/irText/regressions/integerCoercionToT.kt");
             doTest(fileName);
         }
+
+        @TestMetadata("typeAliasCtorForGenericClass.kt")
+        public void testTypeAliasCtorForGenericClass() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/ir/irText/regressions/typeAliasCtorForGenericClass.kt");
+            doTest(fileName);
+        }
     }
 
     @TestMetadata("compiler/testData/ir/irText/singletons")

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/TypeAliasConstructorDescriptor.kt

@@ -34,7 +34,7 @@ interface TypeAliasConstructorDescriptor : ConstructorDescriptor {
 
     override fun getOriginal(): TypeAliasConstructorDescriptor
 
-    override fun substitute(substitutor: TypeSubstitutor): TypeAliasConstructorDescriptor
+    override fun substitute(substitutor: TypeSubstitutor): TypeAliasConstructorDescriptor?
 
     val withDispatchReceiver: TypeAliasConstructorDescriptor?
 
@@ -50,40 +50,46 @@ interface TypeAliasConstructorDescriptor : ConstructorDescriptor {
 class TypeAliasConstructorDescriptorImpl private constructor(
         val storageManager: StorageManager,
         override val typeAliasDescriptor: TypeAliasDescriptor,
-        override val underlyingConstructorDescriptor: ClassConstructorDescriptor,
+        underlyingConstructorDescriptor: ClassConstructorDescriptor,
         original: TypeAliasConstructorDescriptor?,
         annotations: Annotations,
         kind: Kind,
         source: SourceElement
 ) : TypeAliasConstructorDescriptor,
         FunctionDescriptorImpl(typeAliasDescriptor, original, annotations, Name.special("<init>"), kind, source)
 {
-
     // When resolution is ran for common calls, type aliases constructors are resolved as extensions
     // (i.e. after members, and with extension receiver)
     // But when resolving super-calls (with known set of candidates) constructors of inner classes are expected to have
     // a dispatch receiver
     override val withDispatchReceiver: TypeAliasConstructorDescriptor? by storageManager.createNullableLazyValue {
-        val typeAliasConstructor = TypeAliasConstructorDescriptorImpl(storageManager,
-                                                                      typeAliasDescriptor,
-                                                                      underlyingConstructorDescriptor,
-                                                                      this,
-                                                                      underlyingConstructorDescriptor.annotations,
-                                                                      underlyingConstructorDescriptor.kind,
-                                                                      typeAliasDescriptor.source)
-        val substitutorForUnderlyingClass = typeAliasDescriptor.getTypeSubstitutorForUnderlyingClass() ?: return@createNullableLazyValue null
-
-        typeAliasConstructor.initialize(null,
-                                        underlyingConstructorDescriptor.dispatchReceiverParameter?.substitute(substitutorForUnderlyingClass),
-                                        typeAliasDescriptor.declaredTypeParameters,
-                                        valueParameters,
-                                        returnType,
-                                        Modality.FINAL,
-                                        typeAliasDescriptor.visibility)
-
-        return@createNullableLazyValue typeAliasConstructor
+        TypeAliasConstructorDescriptorImpl(
+                storageManager,
+                typeAliasDescriptor,
+                underlyingConstructorDescriptor,
+                this,
+                underlyingConstructorDescriptor.annotations,
+                underlyingConstructorDescriptor.kind,
+                typeAliasDescriptor.source
+        ).also { typeAliasConstructor ->
+            val substitutorForUnderlyingClass = typeAliasDescriptor.getTypeSubstitutorForUnderlyingClass() ?:
+                                                return@createNullableLazyValue null
+
+            typeAliasConstructor.initialize(
+                    null,
+                    underlyingConstructorDescriptor.dispatchReceiverParameter?.substitute(substitutorForUnderlyingClass),
+                    typeAliasDescriptor.declaredTypeParameters,
+                    valueParameters,
+                    returnType,
+                    Modality.FINAL,
+                    typeAliasDescriptor.visibility
+            )
+        }
     }
 
+    override var underlyingConstructorDescriptor: ClassConstructorDescriptor = underlyingConstructorDescriptor
+            private set
+
     override fun isPrimary(): Boolean =
             underlyingConstructorDescriptor.isPrimary
 
@@ -99,8 +105,23 @@ class TypeAliasConstructorDescriptorImpl private constructor(
     override fun getOriginal(): TypeAliasConstructorDescriptor =
             super.getOriginal() as TypeAliasConstructorDescriptor
 
-    override fun substitute(substitutor: TypeSubstitutor): TypeAliasConstructorDescriptor =
-            super.substitute(substitutor) as TypeAliasConstructorDescriptor
+    override fun substitute(substitutor: TypeSubstitutor): TypeAliasConstructorDescriptor? {
+        //    class C<T>(val x: T)
+        //    typealias A<Q> = C<List<Q>>
+        //
+        //    val test = A(listOf(42))
+        //
+        // Here return type for substituted type alias constructor is 'C<List<Int>>',
+        // which yields us a substitution [T -> List<Int>] that should be applied to
+        // the unsubstituted underlying constructor with signature '<T> (T) -> C<T>'
+        // producing substituted underlying constructor with signature '(List<Int>) -> C<List<Int>>'.
+        val substitutedTypeAliasConstructor = super.substitute(substitutor) as TypeAliasConstructorDescriptorImpl
+        val underlyingConstructorSubstitutor = TypeSubstitutor.create(substitutedTypeAliasConstructor.returnType)
+        val substitutedUnderlyingConstructor = underlyingConstructorDescriptor.original.substitute(underlyingConstructorSubstitutor)
+                                               ?: return null
+        substitutedTypeAliasConstructor.underlyingConstructorDescriptor = substitutedUnderlyingConstructor
+        return substitutedTypeAliasConstructor
+    }
 
     override fun copy(
             newOwner: DeclarationDescriptor,