From 6b58be377efc8b1e41ea3e1e3822352ff4b253f9 Mon Sep 17 00:00:00 2001
From: Mikhail Zarechenskiy <mikhail.zarechenskiy@jetbrains.com>
Date: Tue, 2 Jun 2020 15:48:29 +0300
Subject: [PATCH] Fix chained conversions for subtypes of functional types

---
 .../resolve/calls/components/typeConversions.kt | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/components/typeConversions.kt b/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/components/typeConversions.kt
index 1236a68e5a0..0927cdba063 100644
--- a/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/components/typeConversions.kt
+++ b/compiler/resolution/src/org/jetbrains/kotlin/resolve/calls/components/typeConversions.kt
@@ -69,13 +69,20 @@ object TypeConversions {
         val samConvertedType = performConversionAfterSubtyping(
             candidate, argument, candidateParameter, candidateExpectedType, SamTypeConversions
         )
-        if (samConvertedType != null) return samConvertedType
 
-        val suspendConvertedType =
-            performConversionAfterSubtyping(candidate, argument, candidateParameter, candidateExpectedType, SuspendTypeConversions)
-        if (suspendConvertedType != null) return suspendConvertedType
+        val suspendConvertedType = performConversionAfterSubtyping(
+            candidate, argument, candidateParameter,
+            candidateExpectedType = samConvertedType ?: candidateExpectedType,
+            SuspendTypeConversions
+        )
 
-        return performConversionAfterSubtyping(candidate, argument, candidateParameter, candidateExpectedType, UnitTypeConversions)
+        val unitConvertedType = performConversionAfterSubtyping(
+            candidate, argument, candidateParameter,
+            candidateExpectedType = suspendConvertedType ?: samConvertedType ?: candidateExpectedType,
+            UnitTypeConversions
+        )
+
+        return unitConvertedType ?: suspendConvertedType ?: samConvertedType
     }
 
     private fun performConversionAfterSubtyping(