From 0fba58eee7254aed60c6823599ede9fa01674326 Mon Sep 17 00:00:00 2001
From: Mikhail Glukhikh <mikhail.glukhikh@jetbrains.com>
Date: Wed, 15 Nov 2023 18:42:45 +0100
Subject: [PATCH] K2: repeat K1 logic around SAM-based candidates
 discrimination

#KT-56614 Fixed
---
 .../resolve/samConversions/samVsLambda.fir.txt       |  2 +-
 .../kotlin/fir/resolve/calls/ResolutionStages.kt     | 12 +++++++++++-
 .../noCompatibilityResolveForFunInterfaces.fir.kt    |  4 ++--
 .../suspendAndFunConversionInDisabledMode.fir.kt     |  2 +-
 4 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/compiler/fir/analysis-tests/testData/resolve/samConversions/samVsLambda.fir.txt b/compiler/fir/analysis-tests/testData/resolve/samConversions/samVsLambda.fir.txt
index 3cea9985c2a..b4dd4c2f092 100644
--- a/compiler/fir/analysis-tests/testData/resolve/samConversions/samVsLambda.fir.txt
+++ b/compiler/fir/analysis-tests/testData/resolve/samConversions/samVsLambda.fir.txt
@@ -14,7 +14,7 @@ FILE: package2.kt
     }
 FILE: main.kt
     public final fun main(): R|kotlin/Unit| {
-        R|p2/bar|(String(), String(), <L> = bar@fun <anonymous>(): R|kotlin/Unit| <inline=NoInline>  {
+        R|p1/bar|(String(), String(), <L> = bar@fun <anonymous>(): R|kotlin/Unit| <inline=NoInline>  {
             ^@bar Unit
         }
         )
diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt
index 5eba2d3d71d..4c7258090c0 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/ResolutionStages.kt
@@ -9,6 +9,7 @@ import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.fir.FirElement
 import org.jetbrains.kotlin.fir.declarations.*
+import org.jetbrains.kotlin.fir.declarations.utils.isFun
 import org.jetbrains.kotlin.fir.declarations.utils.isInfix
 import org.jetbrains.kotlin.fir.declarations.utils.isOperator
 import org.jetbrains.kotlin.fir.declarations.utils.modality
@@ -486,8 +487,17 @@ internal object CheckArguments : CheckerStage() {
                 sink.yieldDiagnostic(InapplicableCandidate)
             }
 
+            // Logic description: only candidates from Kotlin, but using Java SAM types, are discriminated
             candidate.usesSAM && !candidate.isJavaApplicableCandidate() -> {
-                sink.markCandidateForCompatibilityResolve(context)
+                if (argumentMapping.values.any {
+                        val coneType = it.returnTypeRef.coneType
+                        context.bodyResolveComponents.samResolver.isSamType(coneType) &&
+                                // Candidate is not from Java, so no flexible types are possible here
+                                coneType.toRegularClassSymbol(context.session)?.isJavaOrEnhancement == true
+                    }
+                ) {
+                    sink.markCandidateForCompatibilityResolve(context)
+                }
             }
         }
     }
diff --git a/compiler/testData/diagnostics/tests/funInterface/noCompatibilityResolveForFunInterfaces.fir.kt b/compiler/testData/diagnostics/tests/funInterface/noCompatibilityResolveForFunInterfaces.fir.kt
index f54e65788b0..b093b5023ea 100644
--- a/compiler/testData/diagnostics/tests/funInterface/noCompatibilityResolveForFunInterfaces.fir.kt
+++ b/compiler/testData/diagnostics/tests/funInterface/noCompatibilityResolveForFunInterfaces.fir.kt
@@ -12,7 +12,7 @@ object Test1 {
         fun foo(r: KRunnable) {}
 
         fun test(f: () -> Unit) {
-            <!DEBUG_INFO_CALL("fqName: Test1.foo; typeCall: function")!>foo(f)<!>
+            <!DEBUG_INFO_CALL("fqName: Test1.Scope.foo; typeCall: function")!>foo(f)<!>
         }
     }
 }
@@ -35,7 +35,7 @@ object Test3 {
 
     fun test(f: () -> Unit) {
         val result = foo(1, f)
-        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.String")!>result<!>
+        <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Int")!>result<!>
     }
 }
 
diff --git a/compiler/testData/diagnostics/tests/suspendConversion/suspendAndFunConversionInDisabledMode.fir.kt b/compiler/testData/diagnostics/tests/suspendConversion/suspendAndFunConversionInDisabledMode.fir.kt
index e3d79d82558..99e9f633398 100644
--- a/compiler/testData/diagnostics/tests/suspendConversion/suspendAndFunConversionInDisabledMode.fir.kt
+++ b/compiler/testData/diagnostics/tests/suspendConversion/suspendAndFunConversionInDisabledMode.fir.kt
@@ -12,7 +12,7 @@ object Test1 {
         fun call(r: SuspendRunnable) {}
 
         fun bar(f: () -> Unit) {
-            <!DEBUG_INFO_CALL("fqName: Test1.call; typeCall: function")!>call(f)<!>
+            <!DEBUG_INFO_CALL("fqName: Test1.Scope.call; typeCall: function")!>call(f)<!>
         }
     }
 }