[FIR] Don't capture flexible types that only have projections in one bound

This fixes a false positive NEW_INFERENCE_ERROR.
See the code comment for the rationale.

#KT-63982 Fixed

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

@@ -16430,6 +16430,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
                 runTest("compiler/testData/diagnostics/tests/inference/kt62609.kt");
             }
 
+            @Test
+            @TestMetadata("kt63982.kt")
+            public void testKt63982() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inference/kt63982.kt");
+            }
+
             @Test
             @TestMetadata("lambdaArgumentWithLabel.kt")
             public void testLambdaArgumentWithLabel() throws Exception {

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

@@ -16430,6 +16430,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
                 runTest("compiler/testData/diagnostics/tests/inference/kt62609.kt");
             }
 
+            @Test
+            @TestMetadata("kt63982.kt")
+            public void testKt63982() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inference/kt63982.kt");
+            }
+
             @Test
             @TestMetadata("lambdaArgumentWithLabel.kt")
             public void testLambdaArgumentWithLabel() throws Exception {

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

@@ -16424,6 +16424,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
                 runTest("compiler/testData/diagnostics/tests/inference/kt62609.kt");
             }
 
+            @Test
+            @TestMetadata("kt63982.kt")
+            public void testKt63982() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inference/kt63982.kt");
+            }
+
             @Test
             @TestMetadata("lambdaArgumentWithLabel.kt")
             public void testLambdaArgumentWithLabel() throws Exception {

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

@@ -16430,6 +16430,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
                 runTest("compiler/testData/diagnostics/tests/inference/kt62609.kt");
             }
 
+            @Test
+            @TestMetadata("kt63982.kt")
+            public void testKt63982() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inference/kt63982.kt");
+            }
+
             @Test
             @TestMetadata("lambdaArgumentWithLabel.kt")
             public void testLambdaArgumentWithLabel() throws Exception {

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

@@ -533,32 +533,43 @@ internal fun ConeTypeContext.captureFromExpressionInternal(type: ConeKotlinType)
     fun findCorrespondingCapturedArgumentsForType(type: ConeKotlinType) =
         capturedArgumentsByComponents.find { typeToCapture -> typeToCapture.isSuitableForType(type, this) }?.capturedArguments
 
-    fun replaceArgumentsWithCapturedArgumentsByIntersectionComponents(typeToReplace: ConeSimpleKotlinType): List<ConeKotlinType> {
+    fun replaceArgumentsWithCapturedArgumentsByIntersectionComponents(typeToReplace: ConeSimpleKotlinType): List<ConeKotlinType>? {
         return if (typeToReplace is ConeIntersectionType) {
             typeToReplace.intersectedTypes.map { componentType ->
                 val capturedArguments = findCorrespondingCapturedArgumentsForType(componentType)
                     ?: return@map componentType
                 componentType.withArguments(capturedArguments)
-            }
+            }.takeUnless { it == typeToReplace.intersectedTypes }
         } else {
             val capturedArguments = findCorrespondingCapturedArgumentsForType(typeToReplace)
-                ?: return listOf(typeToReplace)
+                ?: return null
             listOf(typeToReplace.withArguments(capturedArguments))
         }
     }
 
     return when (type) {
         is ConeFlexibleType -> {
-            val lowerIntersectedType = intersectTypes(replaceArgumentsWithCapturedArgumentsByIntersectionComponents(type.lowerBound))
+            // Flexible types can either have projections in both bounds or just the upper bound (raw types and arrays).
-                .withNullability(ConeNullability.create(type.lowerBound.isMarkedNullable), this)
+            // Since the scope of flexible types is built from the lower bound, we don't gain any safety from only capturing the
-            val upperIntersectedType = intersectTypes(replaceArgumentsWithCapturedArgumentsByIntersectionComponents(type.upperBound))
+            // upper bound.
-                .withNullability(ConeNullability.create(type.upperBound.isMarkedNullable), this)
+            // At the same time, capturing of raw(-like) types leads to issues like KT-63982 or breaks tests like
+            // testData/codegen/box/reflection/typeOf/rawTypes_after.kt.
+            // Therefore, we return null if nothing was captured for either bound.
+
+            val lowerIntersectedType =
+                intersectTypes(replaceArgumentsWithCapturedArgumentsByIntersectionComponents(type.lowerBound) ?: return null)
+                    .withNullability(ConeNullability.create(type.lowerBound.isMarkedNullable), this)
+            val upperIntersectedType =
+                intersectTypes(replaceArgumentsWithCapturedArgumentsByIntersectionComponents(type.upperBound) ?: return null)
+                    .withNullability(ConeNullability.create(type.upperBound.isMarkedNullable), this)
 
             ConeFlexibleType(lowerIntersectedType.coneLowerBoundIfFlexible(), upperIntersectedType.coneUpperBoundIfFlexible())
         }
 
         is ConeSimpleKotlinType -> {
-            intersectTypes(replaceArgumentsWithCapturedArgumentsByIntersectionComponents(type)).withNullability(type.isMarkedNullable) as ConeKotlinType
+            intersectTypes(
+                replaceArgumentsWithCapturedArgumentsByIntersectionComponents(type) ?: return null
+            ).withNullability(type.isMarkedNullable) as ConeKotlinType
         }
     }
 }

compiler/testData/diagnostics/tests/inference/kt63982.kt

@@ -0,0 +1,19 @@
+// ISSUE: KT-63982
+// FIR_IDENTICAL
+// DIAGNOSTICS: -DEBUG_INFO_SMARTCAST
+
+// FILE: StubBasedPsiElement.java
+public interface StubBasedPsiElement<Stub extends StubElement> extends PsiElement {
+    Stub getStub();
+}
+
+// FILE: test.kt
+interface PsiElement
+interface JSCallExpression: PsiElement
+interface StubElement<T : PsiElement>
+
+fun test(child: PsiElement) {
+    if (child is JSCallExpression) {
+        val callStub = if (child is StubBasedPsiElement<*>) child.stub else null
+    }
+}

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

@@ -16430,6 +16430,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/inference/kt62609.kt");
             }
 
+            @Test
+            @TestMetadata("kt63982.kt")
+            public void testKt63982() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inference/kt63982.kt");
+            }
+
             @Test
             @TestMetadata("lambdaArgumentWithLabel.kt")
             public void testLambdaArgumentWithLabel() throws Exception {