From db815c96c5c43b09884d704ec067488384cc80dc Mon Sep 17 00:00:00 2001
From: Mikhail Glukhikh <mikhail.glukhikh@jetbrains.com>
Date: Fri, 28 Aug 2020 13:33:33 +0300
Subject: [PATCH] [FIR] Substitute copied type parameters in fake override
 properties

---
 .../scopes/impl/FirClassSubstitutionScope.kt  | 77 +++++++++++++++----
 .../expressions/useImportedMember.fir.txt     |  3 +-
 2 files changed, 63 insertions(+), 17 deletions(-)

diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/scopes/impl/FirClassSubstitutionScope.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/scopes/impl/FirClassSubstitutionScope.kt
index 0fbf4f60ab3..447a8c83011 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/scopes/impl/FirClassSubstitutionScope.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/scopes/impl/FirClassSubstitutionScope.kt
@@ -352,16 +352,9 @@ class FirClassSubstitutionScope(
                     val copiedParameterTypes = baseFunction.valueParameters.map {
                         substitutor.substituteOrNull(it.returnTypeRef.coneType)
                     }
-                    val copiedReceiverType = newReceiverType?.let {
-                        substitutor.substituteOrNull(it)
-                    } ?: baseFunction.receiverTypeRef?.let {
-                        substitutor.substituteOrNull(it.coneType)
-                    }
-                    val copiedReturnType = newReturnType?.let {
-                        substitutor.substituteOrNull(it)
-                    } ?: baseFunction.returnTypeRef.let {
-                        substitutor.substituteOrNull(it.coneType)
-                    }
+                    val (copiedReceiverType, copiedReturnType) = substituteReceiverAndReturnType(
+                        baseFunction as FirCallableMemberDeclaration<*>, newReceiverType, newReturnType, substitutor
+                    )
                     configureAnnotationsAndSignature(session, baseFunction, copiedParameterTypes, copiedReceiverType, copiedReturnType)
                     copiedTypeParameters
                 }
@@ -421,22 +414,74 @@ class FirClassSubstitutionScope(
                 source = baseProperty.source
                 this.session = session
                 origin = FirDeclarationOrigin.FakeOverride
-                returnTypeRef = baseProperty.returnTypeRef.withReplacedReturnType(newReturnType)
-                receiverTypeRef = baseProperty.receiverTypeRef?.withReplacedConeType(newReceiverType)
                 name = baseProperty.name
                 isVar = baseProperty.isVar
                 this.symbol = symbol
                 isLocal = false
                 status = baseProperty.status.withExpect(isExpect)
                 resolvePhase = baseProperty.resolvePhase
-                annotations += baseProperty.annotations
-                if (newTypeParameters != null) {
-                    typeParameters += newTypeParameters
-                }
+                typeParameters += configureAnnotationsTypeParametersAndSignature(baseProperty, newTypeParameters, newReceiverType, newReturnType)
             }
             return symbol
         }
 
+        private fun FirPropertyBuilder.configureAnnotationsTypeParametersAndSignature(
+            baseProperty: FirProperty,
+            newTypeParameters: List<FirTypeParameter>?,
+            newReceiverType: ConeKotlinType? = null,
+            newReturnType: ConeKotlinType? = null
+        ): List<FirTypeParameter> {
+            return when {
+                baseProperty.typeParameters.isEmpty() -> {
+                    configureAnnotationsAndSignature(baseProperty, newReceiverType, newReturnType)
+                    emptyList()
+                }
+                newTypeParameters == null -> {
+                    val (copiedTypeParameters, substitutor) = createNewTypeParametersAndSubstitutor(
+                        baseProperty, ConeSubstitutor.Empty
+                    )
+                    val (copiedReceiverType, copiedReturnType) = substituteReceiverAndReturnType(
+                        baseProperty, newReceiverType, newReturnType, substitutor
+                    )
+                    configureAnnotationsAndSignature(baseProperty, copiedReceiverType, copiedReturnType)
+                    copiedTypeParameters.filterIsInstance<FirTypeParameter>()
+                }
+                else -> {
+                    configureAnnotationsAndSignature(baseProperty, newReceiverType, newReturnType)
+                    newTypeParameters
+                }
+            }
+        }
+
+        private fun substituteReceiverAndReturnType(
+            baseCallable: FirCallableMemberDeclaration<*>,
+            newReceiverType: ConeKotlinType?,
+            newReturnType: ConeKotlinType?,
+            substitutor: ConeSubstitutor
+        ): Pair<ConeKotlinType?, ConeKotlinType?> {
+            val copiedReceiverType = newReceiverType?.let {
+                substitutor.substituteOrNull(it)
+            } ?: baseCallable.receiverTypeRef?.let {
+                substitutor.substituteOrNull(it.coneType)
+            }
+            val copiedReturnType = newReturnType?.let {
+                substitutor.substituteOrNull(it)
+            } ?: baseCallable.returnTypeRef.let {
+                substitutor.substituteOrNull(it.coneType)
+            }
+            return copiedReceiverType to copiedReturnType
+        }
+
+        private fun FirPropertyBuilder.configureAnnotationsAndSignature(
+            baseProperty: FirProperty,
+            newReceiverType: ConeKotlinType? = null,
+            newReturnType: ConeKotlinType? = null
+        ) {
+            annotations += baseProperty.annotations
+            returnTypeRef = baseProperty.returnTypeRef.withReplacedConeType(newReturnType)
+            receiverTypeRef = baseProperty.receiverTypeRef?.withReplacedConeType(newReceiverType)
+        }
+
         fun createFakeOverrideField(
             session: FirSession,
             baseField: FirField,
diff --git a/compiler/testData/ir/irText/expressions/useImportedMember.fir.txt b/compiler/testData/ir/irText/expressions/useImportedMember.fir.txt
index 6c06d09745b..87907acdc09 100644
--- a/compiler/testData/ir/irText/expressions/useImportedMember.fir.txt
+++ b/compiler/testData/ir/irText/expressions/useImportedMember.fir.txt
@@ -124,10 +124,11 @@ FILE fqName:<root> fileName:/useImportedMember.kt
           RETURN type=kotlin.Nothing from='public final fun <get-g2> <T> (): T of <root>.C.<get-g2> declared in <root>.C'
             GET_VAR '<this>: T of <root>.C.<get-g2> declared in <root>.C.<get-g2>' type=T of <root>.C.<get-g2> origin=null
     PROPERTY FAKE_OVERRIDE name:fromClass visibility:public modality:FINAL [fake_override,val]
-      FUN FAKE_OVERRIDE name:<get-fromClass> visibility:public modality:FINAL <> ($this:<root>.BaseClass) returnType:T of <root>.BaseClass.<get-fromClass> [fake_override]
+      FUN FAKE_OVERRIDE name:<get-fromClass> visibility:public modality:FINAL <T> ($this:<root>.BaseClass) returnType:T of <root>.C.<get-fromClass> [fake_override]
         correspondingProperty: PROPERTY FAKE_OVERRIDE name:fromClass visibility:public modality:FINAL [fake_override,val]
         overridden:
           public final fun <get-fromClass> <T> (): T of <root>.BaseClass.<get-fromClass> declared in <root>.BaseClass
+        TYPE_PARAMETER name:T index:0 variance: superTypes:[kotlin.Any?]
         $this: VALUE_PARAMETER name:<this> type:<root>.BaseClass
     FUN FAKE_OVERRIDE name:equals visibility:public modality:OPEN <> ($this:kotlin.Any, other:kotlin.Any?) returnType:kotlin.Boolean [fake_override,operator]
       overridden: