K2: introduce JavaTypeParameterDefaultRepresentationWithDNN exp. feature

#KT-66447 Fixed

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java

@@ -21828,12 +21828,24 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
         runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePosition.kt");
       }
 
+      @Test
+      @TestMetadata("flexibleTypeVariablePositionDnnRepresentation.kt")
+      public void testFlexibleTypeVariablePositionDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePositionDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("futureGet.kt")
       public void testFutureGet() {
         runTest("compiler/testData/diagnostics/tests/j+k/futureGet.kt");
       }
 
+      @Test
+      @TestMetadata("futureGetDnnRepresentation.kt")
+      public void testFutureGetDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/futureGetDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("genericConstructorWithMultipleBounds.kt")
       public void testGenericConstructorWithMultipleBounds() {
@@ -22110,6 +22122,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
         runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueue.kt");
       }
 
+      @Test
+      @TestMetadata("nullableLinkedListToQueueDnnRepresentation.kt")
+      public void testNullableLinkedListToQueueDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueueDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("nullableRawTypeWithFlexibleArguments.kt")
       public void testNullableRawTypeWithFlexibleArguments() {
@@ -23163,6 +23181,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
           runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullable.kt");
         }
 
+        @Test
+        @TestMetadata("notNullTypeParameterWithKotlinNullableDnnRepresentation.kt")
+        public void testNotNullTypeParameterWithKotlinNullableDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("notNullTypeParameterWithKotlinNullableWarnings.kt")
         public void testNotNullTypeParameterWithKotlinNullableWarnings() {
@@ -28692,6 +28716,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
         runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexible.kt");
       }
 
+      @Test
+      @TestMetadata("dnnOverridesFlexibleDnnRepresentation.kt")
+      public void testDnnOverridesFlexibleDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexibleDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("DuplicateMethod.kt")
       public void testDuplicateMethod() {
@@ -29304,6 +29334,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
         runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullability.kt");
       }
 
+      @Test
+      @TestMetadata("comparingWithWrongNullabilityDnnRepresentation.kt")
+      public void testComparingWithWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("delegateByComplexInheritance.kt")
       public void testDelegateByComplexInheritance() {
@@ -29693,6 +29729,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
           runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singleton.kt");
         }
 
+        @Test
+        @TestMetadata("singletonDnnRepresentation.kt")
+        public void testSingletonDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singletonDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("string.kt")
         public void testString() {
@@ -33204,6 +33246,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
         runTest("compiler/testData/diagnostics/tests/samConversions/sameCandidatesFromKotlinAndJavaInOneScope.kt");
       }
 
+      @Test
+      @TestMetadata("sameConversionToGenericWrongNullabilityDnnRepresentation.kt")
+      public void testSameConversionToGenericWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/samConversions/sameConversionToGenericWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("SimpleCorrect.kt")
       public void testSimpleCorrect() {

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java

@@ -21828,12 +21828,24 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
         runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePosition.kt");
       }
 
+      @Test
+      @TestMetadata("flexibleTypeVariablePositionDnnRepresentation.kt")
+      public void testFlexibleTypeVariablePositionDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePositionDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("futureGet.kt")
       public void testFutureGet() {
         runTest("compiler/testData/diagnostics/tests/j+k/futureGet.kt");
       }
 
+      @Test
+      @TestMetadata("futureGetDnnRepresentation.kt")
+      public void testFutureGetDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/futureGetDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("genericConstructorWithMultipleBounds.kt")
       public void testGenericConstructorWithMultipleBounds() {
@@ -22110,6 +22122,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
         runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueue.kt");
       }
 
+      @Test
+      @TestMetadata("nullableLinkedListToQueueDnnRepresentation.kt")
+      public void testNullableLinkedListToQueueDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueueDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("nullableRawTypeWithFlexibleArguments.kt")
       public void testNullableRawTypeWithFlexibleArguments() {
@@ -23163,6 +23181,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
           runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullable.kt");
         }
 
+        @Test
+        @TestMetadata("notNullTypeParameterWithKotlinNullableDnnRepresentation.kt")
+        public void testNotNullTypeParameterWithKotlinNullableDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("notNullTypeParameterWithKotlinNullableWarnings.kt")
         public void testNotNullTypeParameterWithKotlinNullableWarnings() {
@@ -28692,6 +28716,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
         runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexible.kt");
       }
 
+      @Test
+      @TestMetadata("dnnOverridesFlexibleDnnRepresentation.kt")
+      public void testDnnOverridesFlexibleDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexibleDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("DuplicateMethod.kt")
       public void testDuplicateMethod() {
@@ -29304,6 +29334,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
         runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullability.kt");
       }
 
+      @Test
+      @TestMetadata("comparingWithWrongNullabilityDnnRepresentation.kt")
+      public void testComparingWithWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("delegateByComplexInheritance.kt")
       public void testDelegateByComplexInheritance() {
@@ -29693,6 +29729,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
           runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singleton.kt");
         }
 
+        @Test
+        @TestMetadata("singletonDnnRepresentation.kt")
+        public void testSingletonDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singletonDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("string.kt")
         public void testString() {
@@ -33204,6 +33246,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
         runTest("compiler/testData/diagnostics/tests/samConversions/sameCandidatesFromKotlinAndJavaInOneScope.kt");
       }
 
+      @Test
+      @TestMetadata("sameConversionToGenericWrongNullabilityDnnRepresentation.kt")
+      public void testSameConversionToGenericWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/samConversions/sameConversionToGenericWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("SimpleCorrect.kt")
       public void testSimpleCorrect() {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java

@@ -21822,12 +21822,24 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
         runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePosition.kt");
       }
 
+      @Test
+      @TestMetadata("flexibleTypeVariablePositionDnnRepresentation.kt")
+      public void testFlexibleTypeVariablePositionDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePositionDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("futureGet.kt")
       public void testFutureGet() {
         runTest("compiler/testData/diagnostics/tests/j+k/futureGet.kt");
       }
 
+      @Test
+      @TestMetadata("futureGetDnnRepresentation.kt")
+      public void testFutureGetDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/futureGetDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("genericConstructorWithMultipleBounds.kt")
       public void testGenericConstructorWithMultipleBounds() {
@@ -22104,6 +22116,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
         runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueue.kt");
       }
 
+      @Test
+      @TestMetadata("nullableLinkedListToQueueDnnRepresentation.kt")
+      public void testNullableLinkedListToQueueDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueueDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("nullableRawTypeWithFlexibleArguments.kt")
       public void testNullableRawTypeWithFlexibleArguments() {
@@ -23157,6 +23175,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
           runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullable.kt");
         }
 
+        @Test
+        @TestMetadata("notNullTypeParameterWithKotlinNullableDnnRepresentation.kt")
+        public void testNotNullTypeParameterWithKotlinNullableDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("notNullTypeParameterWithKotlinNullableWarnings.kt")
         public void testNotNullTypeParameterWithKotlinNullableWarnings() {
@@ -26390,6 +26414,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
         runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexible.kt");
       }
 
+      @Test
+      @TestMetadata("dnnOverridesFlexibleDnnRepresentation.kt")
+      public void testDnnOverridesFlexibleDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexibleDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("DuplicateMethod.kt")
       public void testDuplicateMethod() {
@@ -27002,6 +27032,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
         runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullability.kt");
       }
 
+      @Test
+      @TestMetadata("comparingWithWrongNullabilityDnnRepresentation.kt")
+      public void testComparingWithWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("delegateByComplexInheritance.kt")
       public void testDelegateByComplexInheritance() {
@@ -27391,6 +27427,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
           runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singleton.kt");
         }
 
+        @Test
+        @TestMetadata("singletonDnnRepresentation.kt")
+        public void testSingletonDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singletonDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("string.kt")
         public void testString() {
@@ -30896,6 +30938,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
         runTest("compiler/testData/diagnostics/tests/samConversions/sameCandidatesFromKotlinAndJavaInOneScope.kt");
       }
 
+      @Test
+      @TestMetadata("sameConversionToGenericWrongNullabilityDnnRepresentation.kt")
+      public void testSameConversionToGenericWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/samConversions/sameConversionToGenericWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("SimpleCorrect.kt")
       public void testSimpleCorrect() {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java

@@ -21828,12 +21828,24 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
         runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePosition.kt");
       }
 
+      @Test
+      @TestMetadata("flexibleTypeVariablePositionDnnRepresentation.kt")
+      public void testFlexibleTypeVariablePositionDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePositionDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("futureGet.kt")
       public void testFutureGet() {
         runTest("compiler/testData/diagnostics/tests/j+k/futureGet.kt");
       }
 
+      @Test
+      @TestMetadata("futureGetDnnRepresentation.kt")
+      public void testFutureGetDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/futureGetDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("genericConstructorWithMultipleBounds.kt")
       public void testGenericConstructorWithMultipleBounds() {
@@ -22110,6 +22122,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
         runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueue.kt");
       }
 
+      @Test
+      @TestMetadata("nullableLinkedListToQueueDnnRepresentation.kt")
+      public void testNullableLinkedListToQueueDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueueDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("nullableRawTypeWithFlexibleArguments.kt")
       public void testNullableRawTypeWithFlexibleArguments() {
@@ -23163,6 +23181,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
           runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullable.kt");
         }
 
+        @Test
+        @TestMetadata("notNullTypeParameterWithKotlinNullableDnnRepresentation.kt")
+        public void testNotNullTypeParameterWithKotlinNullableDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("notNullTypeParameterWithKotlinNullableWarnings.kt")
         public void testNotNullTypeParameterWithKotlinNullableWarnings() {
@@ -26396,6 +26420,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
         runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexible.kt");
       }
 
+      @Test
+      @TestMetadata("dnnOverridesFlexibleDnnRepresentation.kt")
+      public void testDnnOverridesFlexibleDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexibleDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("DuplicateMethod.kt")
       public void testDuplicateMethod() {
@@ -27008,6 +27038,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
         runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullability.kt");
       }
 
+      @Test
+      @TestMetadata("comparingWithWrongNullabilityDnnRepresentation.kt")
+      public void testComparingWithWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("delegateByComplexInheritance.kt")
       public void testDelegateByComplexInheritance() {
@@ -27397,6 +27433,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
           runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singleton.kt");
         }
 
+        @Test
+        @TestMetadata("singletonDnnRepresentation.kt")
+        public void testSingletonDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singletonDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("string.kt")
         public void testString() {
@@ -30908,6 +30950,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
         runTest("compiler/testData/diagnostics/tests/samConversions/sameCandidatesFromKotlinAndJavaInOneScope.kt");
       }
 
+      @Test
+      @TestMetadata("sameConversionToGenericWrongNullabilityDnnRepresentation.kt")
+      public void testSameConversionToGenericWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/samConversions/sameConversionToGenericWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("SimpleCorrect.kt")
       public void testSimpleCorrect() {

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/JavaTypeConversion.kt

@@ -6,10 +6,12 @@
 package org.jetbrains.kotlin.fir.java
 
 import org.jetbrains.kotlin.builtins.jvm.JavaToKotlinClassMap
+import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.diagnostics.ConeSimpleDiagnostic
 import org.jetbrains.kotlin.fir.diagnostics.DiagnosticKind
 import org.jetbrains.kotlin.fir.java.enhancement.readOnlyToMutable
+import org.jetbrains.kotlin.fir.languageVersionSettings
 import org.jetbrains.kotlin.fir.resolve.diagnostics.ConeUnresolvedNameError
 import org.jetbrains.kotlin.fir.resolve.toFirRegularClassSymbol
 import org.jetbrains.kotlin.fir.types.*
@@ -111,7 +113,21 @@ private fun JavaType?.toConeTypeProjection(
             }
             val upperBound = toConeKotlinTypeForFlexibleBound(session, javaTypeParameterStack, mode, attributes, lowerBound)
 
-            if (isRaw) ConeRawType.create(lowerBound, upperBound) else ConeFlexibleType(lowerBound, upperBound)
+            val finalLowerBound = when {
+                !session.languageVersionSettings.supportsFeature(LanguageFeature.JavaTypeParameterDefaultRepresentationWithDNN) ->
+                    lowerBound
+                lowerBound is ConeTypeParameterType ->
+                    ConeDefinitelyNotNullType.create(
+                        lowerBound, session.typeContext,
+                        // Upper bounds might be not initialized properly yet, so we force creating DefinitelyNotNullType
+                        // It should not affect semantics, since it would be still a valid type anyway
+                        avoidComprehensiveCheck = true,
+                    ) ?: lowerBound
+
+                else -> lowerBound
+            }
+
+            if (isRaw) ConeRawType.create(finalLowerBound, upperBound) else ConeFlexibleType(finalLowerBound, upperBound)
         }
 
         is JavaArrayType -> {

compiler/fir/providers/src/org/jetbrains/kotlin/fir/types/ConeInferenceContext.kt

@@ -6,10 +6,13 @@
 package org.jetbrains.kotlin.fir.types
 
 import org.jetbrains.kotlin.builtins.functions.FunctionTypeKind
+import org.jetbrains.kotlin.config.LanguageFeature
+import org.jetbrains.kotlin.config.LanguageVersionSettings
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.fir.declarations.utils.modality
 import org.jetbrains.kotlin.fir.diagnostics.ConeIntermediateDiagnostic
 import org.jetbrains.kotlin.fir.isPrimitiveNumberOrUnsignedNumberType
+import org.jetbrains.kotlin.fir.languageVersionSettings
 import org.jetbrains.kotlin.fir.resolve.createSubstitutionForSupertype
 import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
 import org.jetbrains.kotlin.fir.resolve.providers.FirSymbolProvider
@@ -587,7 +590,9 @@ interface ConeInferenceContext : TypeSystemInferenceExtensionContext, ConeTypeCo
         return intersectionType.withAlternative(secondCandidate)
     }
 
-    override fun useRefinedBoundsForTypeVariableInFlexiblePosition(): Boolean = false
+    override fun useRefinedBoundsForTypeVariableInFlexiblePosition(): Boolean = session.languageVersionSettings.supportsFeature(
+        LanguageFeature.JavaTypeParameterDefaultRepresentationWithDNN
+    )
 
     override fun KotlinTypeMarker.convertToNonRaw(): KotlinTypeMarker {
         require(this is ConeKotlinType)

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/CreateFreshTypeVariableSubstitutorStage.kt

@@ -5,8 +5,10 @@
 
 package org.jetbrains.kotlin.fir.resolve.calls
 
+import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.*
+import org.jetbrains.kotlin.fir.languageVersionSettings
 import org.jetbrains.kotlin.fir.renderWithType
 import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
 import org.jetbrains.kotlin.fir.resolve.inference.ConeTypeParameterBasedTypeVariable
@@ -166,6 +168,9 @@ internal object CreateFreshTypeVariableSubstitutorStage : ResolutionStage() {
     }
 
     private fun FirTypeParameterRef.shouldBeFlexible(context: ConeTypeContext): Boolean {
+        if (context.session.languageVersionSettings.supportsFeature(LanguageFeature.JavaTypeParameterDefaultRepresentationWithDNN)) {
+            return false
+        }
         return symbol.resolvedBounds.any {
             val type = it.coneType
             type is ConeFlexibleType || with(context) {

compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePosition.kt

@@ -1,4 +1,5 @@
 // FIR_IDENTICAL
+// !LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 // ISSUE: KT-59138
 // SKIP_TXT
 // FILE: JavaClass.java
@@ -15,8 +16,8 @@ fun takeN(n: Number?): Int = 1
 fun bar(n: Number?) {
     fun takeN(n: Number): String = ""
 
-    // in K1, it was resolved to nullable takeN
+    // in K1 & K2, it is resolved to nullable takeN
-    // in K2, it would be resolved to not-nullable and may fail with NPE
+    // in K2 with DNN representation ON, it would be resolved to not-nullable and may fail with NPE
     takeN(JavaClass.simpleId(n)).div(1)
     takeN(JavaClass.simpleId(n)).<!UNRESOLVED_REFERENCE!>length<!>
 }

compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePositionDnnRepresentation.fir.kt

@@ -0,0 +1,22 @@
+// !LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-59138
+// SKIP_TXT
+// FILE: JavaClass.java
+public class JavaClass {
+    public static <K> K simpleId(K k) { // fun <K> simpleId(k: K & Any..K?): K & Any..K? =
+        return k;
+    }
+}
+
+// FILE: main.kt
+
+fun takeN(n: Number?): Int = 1
+
+fun bar(n: Number?) {
+    fun takeN(n: Number): String = ""
+
+    // in K1 & K2, it is resolved to nullable takeN
+    // in K2 with DNN representation ON, it would be resolved to not-nullable and may fail with NPE
+    takeN(JavaClass.simpleId(n)).<!UNRESOLVED_REFERENCE!>div<!>(1)
+    takeN(JavaClass.simpleId(n)).length
+}

compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePositionDnnRepresentation.kt

@@ -0,0 +1,22 @@
+// !LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-59138
+// SKIP_TXT
+// FILE: JavaClass.java
+public class JavaClass {
+    public static <K> K simpleId(K k) { // fun <K> simpleId(k: K & Any..K?): K & Any..K? =
+        return k;
+    }
+}
+
+// FILE: main.kt
+
+fun takeN(n: Number?): Int = 1
+
+fun bar(n: Number?) {
+    fun takeN(n: Number): String = ""
+
+    // in K1 & K2, it is resolved to nullable takeN
+    // in K2 with DNN representation ON, it would be resolved to not-nullable and may fail with NPE
+    takeN(JavaClass.simpleId(n)).div(1)
+    takeN(JavaClass.simpleId(n)).<!UNRESOLVED_REFERENCE!>length<!>
+}

compiler/testData/diagnostics/tests/j+k/futureGet.kt

@@ -1,5 +1,6 @@
 // FIR_IDENTICAL
 // FULL_JDK
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 // JVM_TARGET: 1.8
 
 import java.util.concurrent.Future

compiler/testData/diagnostics/tests/j+k/futureGetDnnRepresentation.fir.kt

@@ -0,0 +1,18 @@
+// FULL_JDK
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// JVM_TARGET: 1.8
+
+import java.util.concurrent.Future
+import java.util.concurrent.atomic.AtomicReference
+
+fun foo(future: Future<String?>) {
+    future.get().length
+}
+
+fun bar(threadLocal: ThreadLocal<String?>) {
+    threadLocal.get().length
+}
+
+fun baz(ref: AtomicReference<String?>) {
+    ref.get().length
+}

compiler/testData/diagnostics/tests/j+k/futureGetDnnRepresentation.kt

@@ -0,0 +1,18 @@
+// FULL_JDK
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// JVM_TARGET: 1.8
+
+import java.util.concurrent.Future
+import java.util.concurrent.atomic.AtomicReference
+
+fun foo(future: Future<String?>) {
+    future.get()<!UNSAFE_CALL!>.<!>length
+}
+
+fun bar(threadLocal: ThreadLocal<String?>) {
+    threadLocal.get()<!UNSAFE_CALL!>.<!>length
+}
+
+fun baz(ref: AtomicReference<String?>) {
+    ref.get()<!UNSAFE_CALL!>.<!>length
+}

compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueue.fir.kt

@@ -1,4 +1,5 @@
 // FULL_JDK
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 // ISSUE: KT-65184
 
 // FILE: A.java

compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueue.kt

@@ -1,4 +1,5 @@
 // FULL_JDK
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 // ISSUE: KT-65184
 
 // FILE: A.java

compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueueDnnRepresentation.fir.kt

@@ -0,0 +1,46 @@
+// FULL_JDK
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-65184
+
+// FILE: A.java
+
+public class A<T> {
+
+}
+
+// FILE: B.java
+
+public class B<T> extends A<T> {
+
+}
+
+// FILE: box.kt
+
+import java.util.LinkedList
+import java.util.Queue
+
+fun bar(b: A<String>) {}
+
+fun func(p: A<B<String>>) {
+}
+
+class X {
+    fun bar(b: Queue<String>) {}
+}
+
+fun test(x : X) {
+    x.bar(LinkedList<String?>())
+    bar(B<String?>())
+    func(A<B<String>>())
+    func(<!ARGUMENT_TYPE_MISMATCH!>A<B<String?>>()<!>)
+    func(<!ARGUMENT_TYPE_MISMATCH!>A<B<String?>?>()<!>)
+    func(<!ARGUMENT_TYPE_MISMATCH!>A<B<String>?>()<!>)
+}
+
+class C {
+    fun bar(b: Queue<String>) {}
+}
+
+fun test(c: C, jj: LinkedList<String?>) {
+    c.bar(jj)
+}

compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueueDnnRepresentation.kt

@@ -0,0 +1,46 @@
+// FULL_JDK
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-65184
+
+// FILE: A.java
+
+public class A<T> {
+
+}
+
+// FILE: B.java
+
+public class B<T> extends A<T> {
+
+}
+
+// FILE: box.kt
+
+import java.util.LinkedList
+import java.util.Queue
+
+fun bar(b: A<String>) {}
+
+fun func(p: A<B<String>>) {
+}
+
+class X {
+    fun bar(b: Queue<String>) {}
+}
+
+fun test(x : X) {
+    x.bar(<!TYPE_MISMATCH!>LinkedList<String?>()<!>)
+    bar(<!TYPE_MISMATCH!>B<String?>()<!>)
+    func(A<B<String>>())
+    func(<!TYPE_MISMATCH!>A<B<String?>>()<!>)
+    func(<!TYPE_MISMATCH!>A<B<String?>?>()<!>)
+    func(<!TYPE_MISMATCH!>A<B<String>?>()<!>)
+}
+
+class C {
+    fun bar(b: Queue<String>) {}
+}
+
+fun test(c: C, jj: LinkedList<String?>) {
+    c.bar(<!TYPE_MISMATCH!>jj<!>)
+}

compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullable.fir.kt

@@ -1,5 +1,5 @@
 // !SKIP_JAVAC
-// !LANGUAGE: +ProhibitUsingNullableTypeParameterAgainstNotNullAnnotated
+// !LANGUAGE: +ProhibitUsingNullableTypeParameterAgainstNotNullAnnotated -JavaTypeParameterDefaultRepresentationWithDNN
 // FILE: SLRUMap.java
 
 import org.jetbrains.annotations.NotNull;

compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullable.kt

@@ -1,5 +1,5 @@
 // !SKIP_JAVAC
-// !LANGUAGE: +ProhibitUsingNullableTypeParameterAgainstNotNullAnnotated
+// !LANGUAGE: +ProhibitUsingNullableTypeParameterAgainstNotNullAnnotated -JavaTypeParameterDefaultRepresentationWithDNN
 // FILE: SLRUMap.java
 
 import org.jetbrains.annotations.NotNull;

compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableDnnRepresentation.fir.kt

@@ -0,0 +1,42 @@
+// !SKIP_JAVAC
+// !LANGUAGE: +ProhibitUsingNullableTypeParameterAgainstNotNullAnnotated +JavaTypeParameterDefaultRepresentationWithDNN
+// FILE: SLRUMap.java
+
+import org.jetbrains.annotations.NotNull;
+import java.util.List;
+
+public interface SLRUMap<V> {
+    void takeV(@NotNull V value);
+    <E> void takeE(@NotNull E value);
+
+    void takeVList(@NotNull List<@NotNull V> value);
+    <E> void takeEList(@NotNull List<@NotNull E> value);
+
+    public <K> K id(K value) { return null; }
+}
+
+// FILE: main.kt
+
+fun <V> SLRUMap<V>.getOrPut(value: V, l: List<V>) {
+    takeV(<!ARGUMENT_TYPE_MISMATCH!>value<!>)
+    takeVList(<!ARGUMENT_TYPE_MISMATCH!>l<!>)
+
+    takeE(<!ARGUMENT_TYPE_MISMATCH!>value<!>)
+    takeEList(<!ARGUMENT_TYPE_MISMATCH!>l<!>)
+    takeE(id(value))
+
+    if (value != null) {
+        takeV(value)
+        takeE(value)
+        takeE(id(value))
+    }
+}
+
+fun <V : Any> SLRUMap<V>.getOrPutNN(value: V, l: List<V>) {
+    takeV(value)
+    takeVList(l)
+
+    takeE(value)
+    takeEList(l)
+    takeE(id(value))
+}

compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableDnnRepresentation.kt

@@ -0,0 +1,42 @@
+// !SKIP_JAVAC
+// !LANGUAGE: +ProhibitUsingNullableTypeParameterAgainstNotNullAnnotated +JavaTypeParameterDefaultRepresentationWithDNN
+// FILE: SLRUMap.java
+
+import org.jetbrains.annotations.NotNull;
+import java.util.List;
+
+public interface SLRUMap<V> {
+    void takeV(@NotNull V value);
+    <E> void takeE(@NotNull E value);
+
+    void takeVList(@NotNull List<@NotNull V> value);
+    <E> void takeEList(@NotNull List<@NotNull E> value);
+
+    public <K> K id(K value) { return null; }
+}
+
+// FILE: main.kt
+
+fun <V> SLRUMap<V>.getOrPut(value: V, l: List<V>) {
+    takeV(<!TYPE_MISMATCH!>value<!>)
+    takeVList(<!TYPE_MISMATCH!>l<!>)
+
+    takeE(<!TYPE_MISMATCH!>value<!>)
+    takeEList(<!TYPE_MISMATCH!>l<!>)
+    takeE(<!TYPE_MISMATCH!>id(value)<!>)
+
+    if (value != null) {
+        takeV(<!DEBUG_INFO_SMARTCAST!>value<!>)
+        takeE(<!DEBUG_INFO_SMARTCAST!>value<!>)
+        takeE(id(value))
+    }
+}
+
+fun <V : Any> SLRUMap<V>.getOrPutNN(value: V, l: List<V>) {
+    takeV(value)
+    takeVList(l)
+
+    takeE(value)
+    takeEList(l)
+    takeE(id(value))
+}

compiler/testData/diagnostics/tests/override/dnnOverridesFlexible.kt

@@ -1,4 +1,5 @@
 // FIR_IDENTICAL
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 // ISSUE: KT-58933
 // FILE: J.java
 public interface J<T> {

compiler/testData/diagnostics/tests/override/dnnOverridesFlexibleDnnRepresentation.fir.kt

@@ -0,0 +1,15 @@
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-58933
+// FILE: J.java
+public interface J<T> {
+    void simple(T t);
+    void box(Box<T> box);
+}
+
+// FILE: test.kt
+class Box<T>
+
+class K<T> : J<T> {
+    override fun simple(t: T & Any) {}
+    override fun box(box: Box<T & Any>) {}
+}

compiler/testData/diagnostics/tests/override/dnnOverridesFlexibleDnnRepresentation.kt

@@ -0,0 +1,15 @@
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-58933
+// FILE: J.java
+public interface J<T> {
+    void simple(T t);
+    void box(Box<T> box);
+}
+
+// FILE: test.kt
+class Box<T>
+
+<!ABSTRACT_MEMBER_NOT_IMPLEMENTED!>class K<!><T> : J<T> {
+    <!NOTHING_TO_OVERRIDE!>override<!> fun simple(t: T & Any) {}
+    <!NOTHING_TO_OVERRIDE!>override<!> fun box(box: Box<T & Any>) {}
+}

compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullability.kt

@@ -1,5 +1,6 @@
 // FIR_IDENTICAL
 // FULL_JDK
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 
 import java.util.Comparator;
 

compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullabilityDnnRepresentation.kt

@@ -0,0 +1,11 @@
+// FIR_IDENTICAL
+// FULL_JDK
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+
+import java.util.Comparator;
+
+fun foo() {
+    Comparator.comparing<String?, Boolean?> {
+        it != ""
+    }
+}

compiler/testData/diagnostics/tests/platformTypes/methodCall/singleton.fir.kt

@@ -1,4 +1,5 @@
 // !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 
 interface Foo
 

compiler/testData/diagnostics/tests/platformTypes/methodCall/singleton.kt

@@ -1,4 +1,5 @@
 // !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 
 interface Foo
 

compiler/testData/diagnostics/tests/platformTypes/methodCall/singletonDnnRepresentation.fir.kt

@@ -0,0 +1,10 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+
+interface Foo
+
+fun test() {
+    var nullable: Foo? = null
+    val foo: Collection<Foo> = java.util.Collections.singleton(nullable)
+    val foo1: Collection<Foo> = java.util.Collections.singleton(nullable!!)
+}

compiler/testData/diagnostics/tests/platformTypes/methodCall/singletonDnnRepresentation.kt

@@ -0,0 +1,10 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER -UNUSED_VARIABLE
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+
+interface Foo
+
+fun test() {
+    var nullable: Foo? = null
+    val foo: Collection<Foo> = <!TYPE_MISMATCH!>java.util.Collections.singleton(nullable)<!>
+    val foo1: Collection<Foo> = java.util.Collections.singleton(nullable!!)
+}

compiler/testData/diagnostics/tests/samConversions/samConversionToGenericWrongNullability.kt

@@ -1,4 +1,5 @@
 // FIR_IDENTICAL
+// LANGUAGE: -JavaTypeParameterDefaultRepresentationWithDNN
 // ISSUE: KT-57014
 // FULL_JDK
 // JVM_TARGET: 1.8

compiler/testData/diagnostics/tests/samConversions/sameConversionToGenericWrongNullabilityDnnRepresentation.fir.kt

@@ -0,0 +1,14 @@
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-57014
+// FULL_JDK
+// JVM_TARGET: 1.8
+
+import java.util.function.Supplier
+
+fun main() {
+    val sam = Supplier<String> {
+        <!ARGUMENT_TYPE_MISMATCH!>foo()<!>
+    }
+}
+
+fun foo(): String? = null

compiler/testData/diagnostics/tests/samConversions/sameConversionToGenericWrongNullabilityDnnRepresentation.kt

@@ -0,0 +1,14 @@
+// LANGUAGE: +JavaTypeParameterDefaultRepresentationWithDNN
+// ISSUE: KT-57014
+// FULL_JDK
+// JVM_TARGET: 1.8
+
+import java.util.function.Supplier
+
+fun main() {
+    val sam = Supplier<String> {
+        foo()
+    }
+}
+
+fun foo(): String? = null

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java

@@ -21828,12 +21828,24 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
         runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePosition.kt");
       }
 
+      @Test
+      @TestMetadata("flexibleTypeVariablePositionDnnRepresentation.kt")
+      public void testFlexibleTypeVariablePositionDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/flexibleTypeVariablePositionDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("futureGet.kt")
       public void testFutureGet() {
         runTest("compiler/testData/diagnostics/tests/j+k/futureGet.kt");
       }
 
+      @Test
+      @TestMetadata("futureGetDnnRepresentation.kt")
+      public void testFutureGetDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/futureGetDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("genericConstructorWithMultipleBounds.kt")
       public void testGenericConstructorWithMultipleBounds() {
@@ -22110,6 +22122,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
         runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueue.kt");
       }
 
+      @Test
+      @TestMetadata("nullableLinkedListToQueueDnnRepresentation.kt")
+      public void testNullableLinkedListToQueueDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/j+k/nullableLinkedListToQueueDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("nullableRawTypeWithFlexibleArguments.kt")
       public void testNullableRawTypeWithFlexibleArguments() {
@@ -23163,6 +23181,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
           runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullable.kt");
         }
 
+        @Test
+        @TestMetadata("notNullTypeParameterWithKotlinNullableDnnRepresentation.kt")
+        public void testNotNullTypeParameterWithKotlinNullableDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/j+k/types/notNullTypeParameterWithKotlinNullableDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("notNullTypeParameterWithKotlinNullableWarnings.kt")
         public void testNotNullTypeParameterWithKotlinNullableWarnings() {
@@ -28692,6 +28716,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
         runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexible.kt");
       }
 
+      @Test
+      @TestMetadata("dnnOverridesFlexibleDnnRepresentation.kt")
+      public void testDnnOverridesFlexibleDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/override/dnnOverridesFlexibleDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("DuplicateMethod.kt")
       public void testDuplicateMethod() {
@@ -29304,6 +29334,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
         runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullability.kt");
       }
 
+      @Test
+      @TestMetadata("comparingWithWrongNullabilityDnnRepresentation.kt")
+      public void testComparingWithWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/platformTypes/comparingWithWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("delegateByComplexInheritance.kt")
       public void testDelegateByComplexInheritance() {
@@ -29693,6 +29729,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
           runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singleton.kt");
         }
 
+        @Test
+        @TestMetadata("singletonDnnRepresentation.kt")
+        public void testSingletonDnnRepresentation() {
+          runTest("compiler/testData/diagnostics/tests/platformTypes/methodCall/singletonDnnRepresentation.kt");
+        }
+
         @Test
         @TestMetadata("string.kt")
         public void testString() {
@@ -33204,6 +33246,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
         runTest("compiler/testData/diagnostics/tests/samConversions/sameCandidatesFromKotlinAndJavaInOneScope.kt");
       }
 
+      @Test
+      @TestMetadata("sameConversionToGenericWrongNullabilityDnnRepresentation.kt")
+      public void testSameConversionToGenericWrongNullabilityDnnRepresentation() {
+        runTest("compiler/testData/diagnostics/tests/samConversions/sameConversionToGenericWrongNullabilityDnnRepresentation.kt");
+      }
+
       @Test
       @TestMetadata("SimpleCorrect.kt")
       public void testSimpleCorrect() {

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -384,6 +384,7 @@ enum class LanguageFeature(
     DisableCheckingChangedProgressionsResolve(sinceVersion = null, kind = OTHER), // KT-49276
     ContextSensitiveEnumResolutionInWhen(sinceVersion = null, kind = UNSTABLE_FEATURE), // KT-52774
     ForbidSyntheticPropertiesWithoutBaseJavaGetter(sinceVersion = null, kind = OTHER), // KT-64358
+    JavaTypeParameterDefaultRepresentationWithDNN(sinceVersion = null, kind = OTHER), // KT-59138
     ;
 
     init {