From 5c13e02e9c827eb526ead0ca831b2f0bf97fe4a6 Mon Sep 17 00:00:00 2001
From: Dmitry Savvinov <dmitry.savvinov@jetbrains.com>
Date: Wed, 10 Jul 2019 14:04:07 +0300
Subject: [PATCH] [Misc] Clean-up and deduplicate code in
 'findClassInModule.kt'

---
 .../kotlin/descriptors/findClassInModule.kt   | 30 ++++++++-----------
 1 file changed, 13 insertions(+), 17 deletions(-)

diff --git a/core/descriptors/src/org/jetbrains/kotlin/descriptors/findClassInModule.kt b/core/descriptors/src/org/jetbrains/kotlin/descriptors/findClassInModule.kt
index 0be95d2dce3..ee39a8cc374 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/descriptors/findClassInModule.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/descriptors/findClassInModule.kt
@@ -19,17 +19,26 @@ package org.jetbrains.kotlin.descriptors
 import org.jetbrains.kotlin.incremental.components.NoLookupLocation
 import org.jetbrains.kotlin.name.ClassId
 
-fun ModuleDescriptor.findClassAcrossModuleDependencies(classId: ClassId): ClassDescriptor? {
+fun ModuleDescriptor.findClassifierAcrossModuleDependencies(classId: ClassId): ClassifierDescriptor? {
     val packageViewDescriptor = getPackage(classId.packageFqName)
     val segments = classId.relativeClassName.pathSegments()
-    val topLevelClass = packageViewDescriptor.memberScope.getContributedClassifier(segments.first(), NoLookupLocation.FROM_DESERIALIZATION) as? ClassDescriptor ?: return null
+    val topLevelClass = packageViewDescriptor.memberScope.getContributedClassifier(
+        segments.first(),
+        NoLookupLocation.FROM_DESERIALIZATION
+    ) ?: return null
     var result = topLevelClass
     for (name in segments.subList(1, segments.size)) {
-        result = result.unsubstitutedInnerClassesScope.getContributedClassifier(name, NoLookupLocation.FROM_DESERIALIZATION) as? ClassDescriptor ?: return null
+        if (result !is ClassDescriptor) return null
+        result = result.unsubstitutedInnerClassesScope
+            .getContributedClassifier(name, NoLookupLocation.FROM_DESERIALIZATION) as? ClassDescriptor
+            ?: return null
     }
     return result
 }
 
+fun ModuleDescriptor.findClassAcrossModuleDependencies(classId: ClassId): ClassDescriptor? =
+    findClassifierAcrossModuleDependencies(classId) as? ClassDescriptor
+
 // Returns a mock class descriptor if no existing class is found.
 // NB: the returned class has no type parameters and thus cannot be given arguments in types
 fun ModuleDescriptor.findNonGenericClassAcrossDependencies(classId: ClassId, notFoundClasses: NotFoundClasses): ClassDescriptor {
@@ -43,19 +52,6 @@ fun ModuleDescriptor.findNonGenericClassAcrossDependencies(classId: ClassId, not
 }
 
 fun ModuleDescriptor.findTypeAliasAcrossModuleDependencies(classId: ClassId): TypeAliasDescriptor? {
-    // TODO refactor with findClassAcrossModuleDependencies
     // TODO what if typealias becomes a class / interface?
-
-    val packageViewDescriptor = getPackage(classId.packageFqName)
-    val segments = classId.relativeClassName.pathSegments()
-    val lastNameIndex = segments.size - 1
-    val topLevelClassifier = packageViewDescriptor.memberScope.getContributedClassifier(segments.first(), NoLookupLocation.FROM_DESERIALIZATION)
-    if (lastNameIndex == 0) return topLevelClassifier as? TypeAliasDescriptor
-
-    var currentClass = topLevelClassifier as? ClassDescriptor ?: return null
-    for (name in segments.subList(1, lastNameIndex)) {
-        currentClass = currentClass.unsubstitutedInnerClassesScope.getContributedClassifier(name, NoLookupLocation.FROM_DESERIALIZATION) as? ClassDescriptor ?: return null
-    }
-    val lastName = segments[lastNameIndex]
-    return currentClass.unsubstitutedMemberScope.getContributedClassifier(lastName, NoLookupLocation.FROM_DESERIALIZATION) as? TypeAliasDescriptor
+    return findClassifierAcrossModuleDependencies(classId) as? TypeAliasDescriptor
 }