From 35b475f9f7209b173ecc37e82c23c57346f25c4e Mon Sep 17 00:00:00 2001
From: Mikhail Glukhikh <mikhail.glukhikh@jetbrains.com>
Date: Mon, 12 Jun 2023 15:01:30 +0200
Subject: [PATCH] K2: Fix processing inference lower bound NullableType <: T &
 Any

This commit is a follow-up to 0d070f8ba9afd7f3d8506f9016cb51929724dc72.
Here we remove accidentally returning "Not a sub-type" for a constraint
like TypeVariable <: DNN type

#KT-59241 Fixed
---
 .../TypeCheckerStateForConstraintSystem.kt    |  8 ++++---
 .../notNullTypeParameter/supplier.fir.kt      | 23 -------------------
 .../notNullTypeParameter/supplier.kt          |  1 +
 3 files changed, 6 insertions(+), 26 deletions(-)
 delete mode 100644 compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.fir.kt

diff --git a/compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/inference/components/TypeCheckerStateForConstraintSystem.kt b/compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/inference/components/TypeCheckerStateForConstraintSystem.kt
index 3052ed48e67..11ef367b848 100644
--- a/compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/inference/components/TypeCheckerStateForConstraintSystem.kt
+++ b/compiler/resolution.common/src/org/jetbrains/kotlin/resolve/calls/inference/components/TypeCheckerStateForConstraintSystem.kt
@@ -218,12 +218,15 @@ abstract class TypeCheckerStateForConstraintSystem(
         subType: KotlinTypeMarker,
         isFromNullabilityConstraint: Boolean = false
     ): Boolean = with(extensionTypeContext) {
+        val subTypeConstructor = subType.typeConstructor()
         val lowerConstraint = when (typeVariable) {
             is SimpleTypeMarker ->
                 when {
                     // Foo? (any type which cannot be used as dispatch receiver because of nullability) <: T & Any => ERROR (for K2 only)
-                    isK2 && typeVariable.isDefinitelyNotNullType()
-                            && !AbstractNullabilityChecker.isSubtypeOfAny(extensionTypeContext, subType) -> return false
+                    isK2 && typeVariable.isDefinitelyNotNullType() && !subTypeConstructor.isTypeVariable() &&
+                            !AbstractNullabilityChecker.isSubtypeOfAny(extensionTypeContext, subType) -> {
+                        return false
+                    }
                     /*
                      * Foo <: T? (T is contained in invariant or contravariant positions of a return type) -- Foo <: T
                      *      Example:
@@ -236,7 +239,6 @@ abstract class TypeCheckerStateForConstraintSystem(
                     */
                     typeVariable.isMarkedNullable() -> {
                         val typeVariableTypeConstructor = typeVariable.typeConstructor()
-                        val subTypeConstructor = subType.typeConstructor()
                         val needToMakeDefNotNull = subTypeConstructor.isTypeVariable() ||
                                 typeVariableTypeConstructor !is TypeVariableTypeConstructorMarker ||
                                 !typeVariableTypeConstructor.isContainedInInvariantOrContravariantPositions()
diff --git a/compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.fir.kt b/compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.fir.kt
deleted file mode 100644
index 6dc9246aa0e..00000000000
--- a/compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.fir.kt
+++ /dev/null
@@ -1,23 +0,0 @@
-// FULL_JDK
-
-// FILE: JavaClass.java
-import java.util.function.Supplier;
-import org.jetbrains.annotations.NotNull;
-
-public class JavaClass {
-    public static <E> void consume(@NotNull E value) {}
-    public static <E> void compute(Supplier<@NotNull E> computable) {}
-}
-
-// FILE: KotlinMain.kt
-fun test1() {
-    JavaClass.compute { <!ARGUMENT_TYPE_MISMATCH!>42.apply {}<!> }
-}
-
-fun test2() {
-    JavaClass.compute { <!ARGUMENT_TYPE_MISMATCH!>if (true) 42 else 42<!> }
-}
-
-fun test3() {
-    42.<!INAPPLICABLE_CANDIDATE!>apply<!>(JavaClass::<!UNRESOLVED_REFERENCE!>consume<!>)
-}
diff --git a/compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.kt b/compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.kt
index a58bb08e214..0b106f875e4 100644
--- a/compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.kt
+++ b/compiler/testData/diagnostics/tests/platformTypes/notNullTypeParameter/supplier.kt
@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // FULL_JDK
 
 // FILE: JavaClass.java