Change nestedClasses logic to accept classes with nested type aliases

#KT-47650 fixed

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java

@@ -35521,6 +35521,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
                 runTest("compiler/testData/codegen/box/reflection/classes/nestedClasses.kt");
             }
 
+            @Test
+            @TestMetadata("nestedClassesInScript.kt")
+            public void testNestedClassesInScript() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/classes/nestedClassesInScript.kt");
+            }
+
             @Test
             @TestMetadata("nestedClassesJava.kt")
             public void testNestedClassesJava() throws Exception {

compiler/testData/codegen/box/reflection/classes/nestedClassesInScript.kt

@@ -0,0 +1,22 @@
+// TARGET_BACKEND: JVM
+// IGNORE_BACKEND_FIR: JVM_IR
+// IGNORE_LIGHT_ANALYSIS
+// WITH_RUNTIME
+// WITH_REFLECT
+
+// FILE: test.kt
+
+fun box(): String {
+    val kClass = Script::class
+    val nestedClasses = kClass.nestedClasses
+    val nestedClass = nestedClasses.single()
+    return nestedClass.simpleName!!
+}
+
+
+// FILE: Script.kts
+
+class OK
+typealias Tazz = List<OK>
+val x: Tazz = listOf()
+x

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

@@ -35479,6 +35479,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/reflection/classes/nestedClasses.kt");
             }
 
+            @Test
+            @TestMetadata("nestedClassesInScript.kt")
+            public void testNestedClassesInScript() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/classes/nestedClassesInScript.kt");
+            }
+
             @Test
             @TestMetadata("nestedClassesJava.kt")
             public void testNestedClassesJava() throws Exception {

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

@@ -35521,6 +35521,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/reflection/classes/nestedClasses.kt");
             }
 
+            @Test
+            @TestMetadata("nestedClassesInScript.kt")
+            public void testNestedClassesInScript() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/classes/nestedClassesInScript.kt");
+            }
+
             @Test
             @TestMetadata("nestedClassesJava.kt")
             public void testNestedClassesJava() throws Exception {

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

@@ -28052,6 +28052,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/reflection/classes/nestedClasses.kt");
             }
 
+            @TestMetadata("nestedClassesInScript.kt")
+            public void testNestedClassesInScript() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/classes/nestedClassesInScript.kt");
+            }
+
             @TestMetadata("nestedClassesJava.kt")
             public void testNestedClassesJava() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/classes/nestedClassesJava.kt");

core/reflection.jvm/src/kotlin/reflect/jvm/internal/KClassImpl.kt

@@ -99,7 +99,7 @@ internal class KClassImpl<T : Any>(
         val nestedClasses: Collection<KClass<*>> by ReflectProperties.lazySoft {
             descriptor.unsubstitutedInnerClassesScope.getContributedDescriptors().filterNot(DescriptorUtils::isEnumEntry)
                 .mapNotNull { nestedClass ->
-                    val jClass = (nestedClass as ClassDescriptor).toJavaClass()
+                    val jClass = (nestedClass as? ClassDescriptor)?.toJavaClass()
                     jClass?.let { KClassImpl(it) }
                 }
         }

plugins/scripting/scripting-compiler/build.gradle.kts

@@ -36,6 +36,8 @@ dependencies {
 
     testImplementation(intellijCoreDep()) { includeJars("intellij-core") }
     testRuntimeOnly(intellijDep()) { includeJars("jps-model", "jna") }
+
+    testImplementation(project(":kotlin-reflect"))
 }
 
 sourceSets {

plugins/scripting/scripting-compiler/tests/org/jetbrains/kotlin/scripting/compiler/test/ScriptCompilerTest.kt

@@ -6,7 +6,9 @@
 package org.jetbrains.kotlin.scripting.compiler.test
 
 import junit.framework.TestCase
+import kotlinx.coroutines.runBlocking
 import org.jetbrains.kotlin.scripting.compiler.plugin.impl.ScriptJvmCompilerIsolated
+import kotlin.reflect.KClass
 import kotlin.script.experimental.api.*
 import kotlin.script.experimental.host.toScriptSource
 import kotlin.script.experimental.jvm.defaultJvmScriptingHostConfiguration
@@ -27,6 +29,23 @@ class ScriptCompilerTest : TestCase() {
         assertTrue(res.reports.none { it.message.contains("nonsense") })
     }
 
+    fun testTypeAliases() {
+        val res = compileToClass(
+            """
+                class Clazz
+                typealias Tazz = List<Clazz>
+                val x: Tazz = listOf()
+                x
+            """.trimIndent().toScriptSource()
+        )
+
+        val kclass = res.valueOrThrow()
+        val nestedClasses = kclass.nestedClasses.toList()
+
+        assertEquals(1, nestedClasses.size)
+        assertEquals("Clazz", nestedClasses[0].simpleName)
+    }
+
     fun compile(
         script: SourceCode,
         cfgBody: ScriptCompilationConfiguration.Builder.() -> Unit
@@ -35,4 +54,14 @@ class ScriptCompilerTest : TestCase() {
         val compiler = ScriptJvmCompilerIsolated(defaultJvmScriptingHostConfiguration)
         return compiler.compile(script, compilationConfiguration)
     }
+
+    fun compileToClass(
+        script: SourceCode,
+        evaluationConfiguration: ScriptEvaluationConfiguration = ScriptEvaluationConfiguration(),
+        cfgBody: ScriptCompilationConfiguration.Builder.() -> Unit = {},
+    ): ResultWithDiagnostics<KClass<*>> {
+        val result = compile(script, cfgBody)
+        if (result is ResultWithDiagnostics.Failure) return result
+        return runBlocking { result.valueOrThrow().getClass(evaluationConfiguration) }
+    }
 }