JVM_IR: keep nullability when remapping type parameters

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt

@@ -294,7 +294,7 @@ fun IrType.remapTypeParameters(source: IrTypeParametersContainer, target: IrType
             val classifier = classifier.owner
             when {
                 classifier is IrTypeParameter && classifier.parent == source ->
-                    target.typeParameters[classifier.index + shift].defaultType
+                    IrSimpleTypeImpl(target.typeParameters[classifier.index + shift].symbol, hasQuestionMark, arguments, annotations)
 
                 classifier is IrClass ->
                     IrSimpleTypeImpl(

compiler/testData/codegen/box/javaInterop/notNullAssertions/nonNullableTypeParameter.kt

@@ -0,0 +1,22 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// TARGET_BACKEND: JVM
+// FILE: a.kt
+interface I {
+    fun <T : String> f(x: T) = x
+}
+
+class C : I
+
+fun box() = try {
+    B.f()
+    "FAIL"
+} catch (e: IllegalArgumentException) {
+    "OK"
+}
+
+// FILE: B.java
+public class B {
+    public static String f() {
+        return new C().<String>f(null);
+    }
+}

compiler/testData/codegen/box/javaInterop/notNullAssertions/nullableTypeParameter.kt

@@ -0,0 +1,9 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// TARGET_BACKEND: JVM
+interface I {
+    fun <T : String> f(x: T?) = x ?: "OK"
+}
+
+class C : I
+
+fun box() = C().f<String>(null)

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -14514,6 +14514,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/mapPut.kt");
             }
 
+            @TestMetadata("nonNullableTypeParameter.kt")
+            public void testNonNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nonNullableTypeParameter.kt");
+            }
+
             @TestMetadata("nullabilityAssertionOnDispatchReceiver.kt")
             public void testNullabilityAssertionOnDispatchReceiver() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnDispatchReceiver.kt");
@@ -14539,6 +14544,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnPrivateMemberExtensionReceiver.kt");
             }
 
+            @TestMetadata("nullableTypeParameter.kt")
+            public void testNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullableTypeParameter.kt");
+            }
+
             @TestMetadata("paramAssertionMessage.kt")
             public void testParamAssertionMessage() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/paramAssertionMessage.kt");

compiler/tests/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -14514,6 +14514,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/mapPut.kt");
             }
 
+            @TestMetadata("nonNullableTypeParameter.kt")
+            public void testNonNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nonNullableTypeParameter.kt");
+            }
+
             @TestMetadata("nullabilityAssertionOnDispatchReceiver.kt")
             public void testNullabilityAssertionOnDispatchReceiver() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnDispatchReceiver.kt");
@@ -14539,6 +14544,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnPrivateMemberExtensionReceiver.kt");
             }
 
+            @TestMetadata("nullableTypeParameter.kt")
+            public void testNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullableTypeParameter.kt");
+            }
+
             @TestMetadata("paramAssertionMessage.kt")
             public void testParamAssertionMessage() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/paramAssertionMessage.kt");

compiler/tests/org/jetbrains/kotlin/codegen/ir/FirBlackBoxCodegenTestGenerated.java

@@ -13364,6 +13364,11 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/mapPut.kt");
             }
 
+            @TestMetadata("nonNullableTypeParameter.kt")
+            public void testNonNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nonNullableTypeParameter.kt");
+            }
+
             @TestMetadata("nullabilityAssertionOnDispatchReceiver.kt")
             public void testNullabilityAssertionOnDispatchReceiver() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnDispatchReceiver.kt");
@@ -13389,6 +13394,11 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnPrivateMemberExtensionReceiver.kt");
             }
 
+            @TestMetadata("nullableTypeParameter.kt")
+            public void testNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullableTypeParameter.kt");
+            }
+
             @TestMetadata("paramAssertionMessage.kt")
             public void testParamAssertionMessage() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/paramAssertionMessage.kt");

compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBlackBoxCodegenTestGenerated.java

@@ -13364,6 +13364,11 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/mapPut.kt");
             }
 
+            @TestMetadata("nonNullableTypeParameter.kt")
+            public void testNonNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nonNullableTypeParameter.kt");
+            }
+
             @TestMetadata("nullabilityAssertionOnDispatchReceiver.kt")
             public void testNullabilityAssertionOnDispatchReceiver() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnDispatchReceiver.kt");
@@ -13389,6 +13394,11 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullabilityAssertionOnPrivateMemberExtensionReceiver.kt");
             }
 
+            @TestMetadata("nullableTypeParameter.kt")
+            public void testNullableTypeParameter() throws Exception {
+                runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/nullableTypeParameter.kt");
+            }
+
             @TestMetadata("paramAssertionMessage.kt")
             public void testParamAssertionMessage() throws Exception {
                 runTest("compiler/testData/codegen/box/javaInterop/notNullAssertions/paramAssertionMessage.kt");