Fix infinite recursion during indexing types (EA-86494)

idea/idea-analysis/src/org/jetbrains/kotlin/idea/stubindex/IndexUtils.kt

@@ -19,7 +19,10 @@ package org.jetbrains.kotlin.idea.stubindex
 import com.intellij.psi.stubs.IndexSink
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
-import org.jetbrains.kotlin.psi.stubs.*
+import org.jetbrains.kotlin.psi.stubs.KotlinCallableStubBase
+import org.jetbrains.kotlin.psi.stubs.KotlinModifierListStub
+import org.jetbrains.kotlin.psi.stubs.KotlinStubWithFqName
+import org.jetbrains.kotlin.psi.stubs.KotlinTypeAliasStub
 import org.jetbrains.kotlin.psi.stubs.elements.KtStubElementTypes
 import org.jetbrains.kotlin.util.aliasImportMap
 
@@ -27,10 +30,12 @@ fun <TDeclaration : KtCallableDeclaration> indexTopLevelExtension(stub: KotlinCa
     if (stub.isExtension()) {
         val declaration = stub.psi
         val containingTypeReference = declaration.receiverTypeReference!!
-        containingTypeReference.typeElement?.index(declaration, containingTypeReference) { typeName ->
+        index(containingTypeReference.typeElement, declaration, containingTypeReference) { typeName ->
             val name = declaration.name ?: return@index
-            sink.occurrence(KotlinTopLevelExtensionsByReceiverTypeIndex.INSTANCE.key,
+            sink.occurrence(
-                            KotlinTopLevelExtensionsByReceiverTypeIndex.buildKey(typeName, name))
+                KotlinTopLevelExtensionsByReceiverTypeIndex.INSTANCE.key,
+                KotlinTopLevelExtensionsByReceiverTypeIndex.buildKey(typeName, name)
+            )
         }
     }
 }
@@ -39,53 +44,68 @@ fun indexTypeAliasExpansion(stub: KotlinTypeAliasStub, sink: IndexSink) {
     val declaration = stub.psi
     val typeReference = declaration.getTypeReference() ?: return
     val typeElement = typeReference.typeElement ?: return
-    typeElement.index(declaration, typeReference) { typeName ->
+    index(typeElement, declaration, typeReference) { typeName ->
         sink.occurrence(KotlinTypeAliasByExpansionShortNameIndex.KEY, typeName)
     }
 }
 
-private fun KtTypeElement.index(
+private fun index(
+    typeElement: KtTypeElement?,
+    declaration: KtTypeParameterListOwner,
+    containingTypeReference: KtTypeReference,
+    occurrence: (String) -> Unit
+) {
+    fun internalIndex(
+        typeElement: KtTypeElement?,
         declaration: KtTypeParameterListOwner,
         containingTypeReference: KtTypeReference,
+        visited: MutableSet<KtTypeElement>,
         occurrence: (String) -> Unit
-) {
+    ) {
-    when (this) {
+        if (typeElement == null) return
-        is KtUserType -> {
+        if (typeElement in visited) return
-            val referenceName = referencedName ?: return
 
-            val typeParameter = declaration.typeParameters.firstOrNull { it.name == referenceName }
+        visited.add(typeElement)
-            if (typeParameter != null) {
+
-                val bound = typeParameter.extendsBound
+        when (typeElement) {
-                if (bound != null) {
+            is KtUserType -> {
-                    bound.typeElement?.index(declaration, containingTypeReference, occurrence)
+                val referenceName = typeElement.referencedName ?: return
+
+                val typeParameter = declaration.typeParameters.firstOrNull { it.name == referenceName }
+                if (typeParameter != null) {
+                    val bound = typeParameter.extendsBound
+                    if (bound != null) {
+                        internalIndex(bound.typeElement, declaration, containingTypeReference, visited, occurrence)
+                    } else {
+                        occurrence("Any")
+                    }
+                    return
                 }
-                else {
+
-                    occurrence("Any")
+                occurrence(referenceName)
-                }
+
-                return
+                typeElement.aliasImportMap()[referenceName].forEach { occurrence(it) }
             }
 
-            occurrence(referenceName)
+            is KtNullableType -> internalIndex(typeElement.innerType, declaration, containingTypeReference, visited, occurrence)
 
-            aliasImportMap()[referenceName].forEach { occurrence(it) }
+            is KtFunctionType -> {
-        }
+                val arity = typeElement.parameters.size + (if (typeElement.receiverTypeReference != null) 1 else 0)
-
+                val suspendPrefix =
-        is KtNullableType -> innerType?.index(declaration, containingTypeReference, occurrence)
-
-        is KtFunctionType -> {
-            val arity = parameters.size + (if (receiverTypeReference != null) 1 else 0)
-            val suspendPrefix =
                     if (containingTypeReference.modifierList?.hasModifier(KtTokens.SUSPEND_KEYWORD) == true)
                         "Suspend"
                     else
                         ""
-            occurrence("${suspendPrefix}Function$arity")
+                occurrence("${suspendPrefix}Function$arity")
+            }
+
+            is KtDynamicType -> occurrence("Any")
+
+            else -> error("Unsupported type: $typeElement")
         }
-
-        is KtDynamicType -> occurrence("Any")
-
-        else -> error("Unsupported type: $this")
     }
+
+    internalIndex(typeElement, declaration, containingTypeReference, mutableSetOf(), occurrence)
 }
 
 fun indexInternals(stub: KotlinCallableStubBase<*>, sink: IndexSink) {

idea/testData/typealiasExpansionIndex/recursion.kt

@@ -0,0 +1 @@
+//fun <T: T> T.some() {}

idea/tests/org/jetbrains/kotlin/idea/KotlinTypeAliasByExpansionShortNameIndexTestGenerated.java

@@ -39,6 +39,11 @@ public class KotlinTypeAliasByExpansionShortNameIndexTestGenerated extends Abstr
         runTest("idea/testData/typealiasExpansionIndex/generics.kt");
     }
 
+    @TestMetadata("recursion.kt")
+    public void testRecursion() throws Exception {
+        runTest("idea/testData/typealiasExpansionIndex/recursion.kt");
+    }
+
     @TestMetadata("simpleType.kt")
     public void testSimpleType() throws Exception {
         runTest("idea/testData/typealiasExpansionIndex/simpleType.kt");