From 541f6b0c886005fa4a6dce248dbfb96c8dc4195a Mon Sep 17 00:00:00 2001
From: Pavel Kunyavskiy <pavel.kunyavskiy@jetbrains.com>
Date: Wed, 12 Jan 2022 15:23:56 +0300
Subject: [PATCH] [K/N] Fix handling of legacy suspend-function superclass

^KT-50737
---
 .../lower/AbstractSuspendFunctionsLowering.kt |  8 ++-
 .../backend.native/tests/build.gradle         |  5 ++
 .../tests/codegen/coroutines/inheritance.kt   | 49 +++++++++++++++++++
 .../tests/codegen/coroutines/inheritance.out  |  2 +
 4 files changed, 63 insertions(+), 1 deletion(-)
 create mode 100644 kotlin-native/backend.native/tests/codegen/coroutines/inheritance.kt
 create mode 100644 kotlin-native/backend.native/tests/codegen/coroutines/inheritance.out

diff --git a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/AbstractSuspendFunctionsLowering.kt b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/AbstractSuspendFunctionsLowering.kt
index 2f953533beb..0c0db54a20a 100644
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/AbstractSuspendFunctionsLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/AbstractSuspendFunctionsLowering.kt
@@ -71,8 +71,14 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
                 declaration.acceptChildrenVoid(this)
             }
 
+
             private fun addMissingSupertypes(clazz: IrClass) {
-                val suspendFunctionTypes = getAllSubstitutedSupertypes(clazz).filter { it.isSuspendFunction() }.toSet()
+                val suspendFunctionTypes = getAllSubstitutedSupertypes(clazz).filter {
+                    // SuspendFunction class is some hack in old Kotlin/Native compiler versions.
+                    // It's not used now, but is considered as SuspendFunction-like class in isSuspendFunction util,
+                    // if found in old klib. We need just to ignore it.
+                    it.isSuspendFunction() && it.classOrNull?.owner?.name?.toString() != "SuspendFunction"
+                }.toSet()
 
                 for (suspendFunctionType in suspendFunctionTypes) {
                     val suspendFunctionClassSymbol = suspendFunctionType.classOrNull ?: continue
diff --git a/kotlin-native/backend.native/tests/build.gradle b/kotlin-native/backend.native/tests/build.gradle
index ad6cbbff42a..f2cb93535b0 100644
--- a/kotlin-native/backend.native/tests/build.gradle
+++ b/kotlin-native/backend.native/tests/build.gradle
@@ -2204,6 +2204,11 @@ task coroutines_kt41394(type: KonanLocalTest) {
     source = "codegen/coroutines/kt41394.kt"
 }
 
+task coroutines_inheritance(type: KonanLocalTest) {
+    useGoldenData = true
+    source = "codegen/coroutines/inheritance.kt"
+}
+
 standaloneTest('coroutines_suspendConversion') {
     useGoldenData = true
     source = "codegen/coroutines/suspendConversion.kt"
diff --git a/kotlin-native/backend.native/tests/codegen/coroutines/inheritance.kt b/kotlin-native/backend.native/tests/codegen/coroutines/inheritance.kt
new file mode 100644
index 00000000000..df48169e28f
--- /dev/null
+++ b/kotlin-native/backend.native/tests/codegen/coroutines/inheritance.kt
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2010-2022 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 codegen.coroutines.inheritance
+
+import kotlin.test.*
+
+import kotlin.coroutines.*
+import kotlin.coroutines.intrinsics.*
+
+open class EmptyContinuation(override val context: CoroutineContext = EmptyCoroutineContext) : Continuation<Any?> {
+    companion object : EmptyContinuation()
+    override fun resumeWith(result: Result<Any?>) { result.getOrThrow() }
+}
+
+class SuspendHere(): suspend () -> Int {
+    override suspend fun invoke() : Int = suspendCoroutineUninterceptedOrReturn { x ->
+        x.resume(42)
+        COROUTINE_SUSPENDED
+    }
+}
+
+// in old compiler versions all suspend functions were implementing this interface
+// now they are not, but let's test it works correctly
+class SuspendHereLegacy(): suspend () -> Int, SuspendFunction<Int> {
+    override suspend fun invoke() : Int = suspendCoroutineUninterceptedOrReturn { x ->
+        x.resume(43)
+        COROUTINE_SUSPENDED
+    }
+}
+
+fun builder(c: suspend () -> Unit) {
+    c.startCoroutine(EmptyContinuation)
+}
+
+@Test fun runTest() {
+    var result = 0
+
+    builder {
+        result = SuspendHere()()
+    }
+    println(result)
+    builder {
+        result = SuspendHereLegacy()()
+    }
+    println(result)
+}
\ No newline at end of file
diff --git a/kotlin-native/backend.native/tests/codegen/coroutines/inheritance.out b/kotlin-native/backend.native/tests/codegen/coroutines/inheritance.out
new file mode 100644
index 00000000000..6fe5c7f6a8f
--- /dev/null
+++ b/kotlin-native/backend.native/tests/codegen/coroutines/inheritance.out
@@ -0,0 +1,2 @@
+42
+43