From 820c2c7cd88f9acafe9cbca9fb7abb19a8cfceb6 Mon Sep 17 00:00:00 2001
From: Valentin Kipyatkov <valentin@jetbrains.com>
Date: Wed, 26 Nov 2014 17:58:18 +0300
Subject: [PATCH] Smart completion: inheritors instantiation suggested + fixed
 a bug with incorrect presentation of generic java class instantiation

---
 .../Smart_Completion_Tests.xml                |   2 +
 .../jet/lang/types/SubstitutionUtils.java     |   2 +-
 .../caches/resolve/KotlinCacheService.kt      |   4 +
 .../plugin/caches/resolve/ResolutionFacade.kt |   2 +
 .../plugin/completion/CompletionSession.kt    |  12 +-
 .../completion/smart/SmartCompletion.kt       |  33 ++++-
 .../smart/TypeInstantiationItems.kt           | 139 ++++++++++++++++--
 .../jet/plugin/completion/smart/Utils.kt      |   1 +
 .../smart/AnonymousObjectInsertsImport.kt     |   2 +-
 .../AnonymousObjectInsertsImport.kt.after     |   2 +-
 .../handlers/smart/ConstructorForJavaClass.kt |   3 +
 .../smart/ConstructorForJavaClass.kt.after    |   3 +
 .../completion/handlers/smart/SAMExpected1.kt |   3 +-
 .../handlers/smart/SAMExpected1.kt.after      |   3 +-
 .../smart/ConstructorForGenericJavaClass.kt   |   5 +
 .../ConstructorForGenericJavaClass.kt.todo    |   5 -
 idea/testData/completion/smart/Inheritors1.kt |   8 +
 idea/testData/completion/smart/Inheritors2.kt |   5 +
 .../GenericInheritors1/GenericInheritors1.kt  |  15 ++
 .../GenericInheritors1/JavaInheritors.java    |   6 +
 .../GenericInheritors1/KotlinInheritors.kt    |  23 +++
 .../GenericInheritors2/GenericInheritors2.kt  |   8 +
 .../GenericInheritors2/KotlinInheritors.kt    |  11 ++
 .../GenericInheritors3/GenericInheritors3.kt  |   8 +
 .../GenericInheritors3/KotlinInheritors.kt    |  11 ++
 .../GenericInheritors4/GenericInheritors4.kt  |   8 +
 .../GenericInheritors4/KotlinInheritors.kt    |  10 ++
 .../smartMultiFile/Inheritors/Inheritors.kt   |  15 ++
 .../Inheritors/JavaInheritors.java            |  16 ++
 .../Inheritors/KotlinInheritors.kt            |  17 +++
 .../JvmSmartCompletionTestGenerated.java      |  19 ++-
 ...MultiFileSmartCompletionTestGenerated.java |  30 ++++
 .../jet/plugin/KotlinCompletionTestCase.java  |   1 -
 33 files changed, 396 insertions(+), 36 deletions(-)
 create mode 100644 idea/testData/completion/smart/ConstructorForGenericJavaClass.kt
 delete mode 100644 idea/testData/completion/smart/ConstructorForGenericJavaClass.kt.todo
 create mode 100644 idea/testData/completion/smart/Inheritors1.kt
 create mode 100644 idea/testData/completion/smart/Inheritors2.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors1/GenericInheritors1.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors1/JavaInheritors.java
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors1/KotlinInheritors.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors2/GenericInheritors2.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors2/KotlinInheritors.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors3/GenericInheritors3.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors3/KotlinInheritors.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors4/GenericInheritors4.kt
 create mode 100644 idea/testData/completion/smartMultiFile/GenericInheritors4/KotlinInheritors.kt
 create mode 100644 idea/testData/completion/smartMultiFile/Inheritors/Inheritors.kt
 create mode 100644 idea/testData/completion/smartMultiFile/Inheritors/JavaInheritors.java
 create mode 100644 idea/testData/completion/smartMultiFile/Inheritors/KotlinInheritors.kt

diff --git a/.idea/runConfigurations/Smart_Completion_Tests.xml b/.idea/runConfigurations/Smart_Completion_Tests.xml
index 421247549ac..3f27f24afea 100644
--- a/.idea/runConfigurations/Smart_Completion_Tests.xml
+++ b/.idea/runConfigurations/Smart_Completion_Tests.xml
@@ -28,6 +28,8 @@
       <pattern testClass="org.jetbrains.jet.completion.JvmSmartCompletionTestGenerated" />
       <pattern testClass="org.jetbrains.jet.completion.handlers.SmartCompletionHandlerTestGenerated" />
       <pattern testClass="org.jetbrains.jet.completion.handlers.SmartCompletionMultifileHandlerTest" />
+      <pattern testClass="org.jetbrains.jet.completion.weighers.SmartCompletionWeigherTestGenerated" />
+      <pattern testClass="org.jetbrains.jet.completion.MultiFileSmartCompletionTestGenerated" />
     </patterns>
     <RunnerSettings RunnerId="Debug">
       <option name="DEBUG_PORT" value="" />
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/types/SubstitutionUtils.java b/compiler/frontend/src/org/jetbrains/jet/lang/types/SubstitutionUtils.java
index cd1c66315d5..5504530a8f5 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/types/SubstitutionUtils.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/types/SubstitutionUtils.java
@@ -43,7 +43,7 @@ public class SubstitutionUtils {
         return typeSubstitutor;
     }
 
-    /*
+    /**
       For each supertype of a given type, we map type parameters to type arguments.
 
       For instance, we have the following class hierarchy:
diff --git a/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/KotlinCacheService.kt b/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/KotlinCacheService.kt
index 35c15ad6aab..62271643f95 100644
--- a/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/KotlinCacheService.kt
+++ b/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/KotlinCacheService.kt
@@ -68,6 +68,10 @@ public class KotlinCacheService(val project: Project) {
             override fun analyzeFullyAndGetResult(elements: Collection<JetElement>): AnalysisResult {
                 return cache.getAnalysisResultsForElements(elements)
             }
+
+            override fun <T> get(extension: CacheExtension<T>): T {
+                return cache[extension]
+            }
         }
     }
 
diff --git a/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/ResolutionFacade.kt b/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/ResolutionFacade.kt
index 1352c63c51f..4e6df6847f1 100644
--- a/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/ResolutionFacade.kt
+++ b/idea/idea-analysis/src/org/jetbrains/jet/plugin/caches/resolve/ResolutionFacade.kt
@@ -34,4 +34,6 @@ public trait ResolutionFacade {
     public fun resolveToDescriptor(declaration: JetDeclaration): DeclarationDescriptor
 
     public fun findModuleDescriptor(element: JetElement): ModuleDescriptor
+
+    public fun <T> get(extension: CacheExtension<T>): T
 }
diff --git a/idea/src/org/jetbrains/jet/plugin/completion/CompletionSession.kt b/idea/src/org/jetbrains/jet/plugin/completion/CompletionSession.kt
index baa12d51479..8cf13536f10 100644
--- a/idea/src/org/jetbrains/jet/plugin/completion/CompletionSession.kt
+++ b/idea/src/org/jetbrains/jet/plugin/completion/CompletionSession.kt
@@ -229,7 +229,9 @@ class SmartCompletionSession(configuration: CompletionSessionConfiguration, para
 
     override fun doComplete() {
         if (jetReference != null) {
-            val completion = SmartCompletion(jetReference.expression, resolutionFacade, bindingContext!!, { isVisibleDescriptor(it) }, parameters.getOriginalFile() as JetFile, boldImmediateLookupElementFactory)
+            val completion = SmartCompletion(jetReference.expression, resolutionFacade, moduleDescriptor, 
+                                             bindingContext!!, { isVisibleDescriptor(it) }, searchScope,
+                                             parameters.getOriginalFile() as JetFile, boldImmediateLookupElementFactory)
             val result = completion.execute()
             if (result != null) {
                 collector.addElements(result.additionalItems)
@@ -237,10 +239,15 @@ class SmartCompletionSession(configuration: CompletionSessionConfiguration, para
                 val filter = result.declarationFilter
                 if (filter != null) {
                     getReferenceVariants(DESCRIPTOR_KIND_MASK).forEach { collector.addElements(filter(it)) }
-
                     flushToResultSet()
 
                     processNonImported { collector.addElements(filter(it)) }
+                    flushToResultSet()
+                }
+
+                result.inheritanceSearcher?.search({ prefixMatcher.prefixMatches(it) }) {
+                    collector.addElement(it)
+                    flushToResultSet()
                 }
             }
         }
@@ -249,7 +256,6 @@ class SmartCompletionSession(configuration: CompletionSessionConfiguration, para
     private fun processNonImported(processor: (DeclarationDescriptor) -> Unit) {
         if (shouldRunTopLevelCompletion()) {
             getKotlinTopLevelCallables().forEach(processor)
-            getKotlinTopLevelObjects().forEach(processor) //TODO: shouldn't it work via inheritors search?
         }
 
         if (shouldRunExtensionsCompletion()) {
diff --git a/idea/src/org/jetbrains/jet/plugin/completion/smart/SmartCompletion.kt b/idea/src/org/jetbrains/jet/plugin/completion/smart/SmartCompletion.kt
index 21734624160..b7525ed8768 100644
--- a/idea/src/org/jetbrains/jet/plugin/completion/smart/SmartCompletion.kt
+++ b/idea/src/org/jetbrains/jet/plugin/completion/smart/SmartCompletion.kt
@@ -34,17 +34,26 @@ import org.jetbrains.jet.lang.psi.psiUtil.getReceiverExpression
 import org.jetbrains.jet.plugin.util.IdeDescriptorRenderers
 import org.jetbrains.jet.plugin.caches.resolve.ResolutionFacade
 import org.jetbrains.jet.plugin.caches.resolve.resolveToDescriptor
+import com.intellij.psi.search.GlobalSearchScope
+
+trait InheritanceItemsSearcher {
+    fun search(nameFilter: (String) -> Boolean, consumer: (LookupElement) -> Unit)
+}
 
 class SmartCompletion(val expression: JetSimpleNameExpression,
                       val resolutionFacade: ResolutionFacade,
+                      val moduleDescriptor: ModuleDescriptor,
                       val bindingContext: BindingContext,
                       val visibilityFilter: (DeclarationDescriptor) -> Boolean,
+                      val searchScope: GlobalSearchScope,
                       val originalFile: JetFile,
                       val boldImmediateLookupElementFactory: LookupElementFactory) {
     private val project = expression.getProject()
 
-    public data class Result(val declarationFilter: ((DeclarationDescriptor) -> Collection<LookupElement>)?,
-                             val additionalItems: Collection<LookupElement>)
+    public class Result(
+            val declarationFilter: ((DeclarationDescriptor) -> Collection<LookupElement>)?,
+            val additionalItems: Collection<LookupElement>,
+            val inheritanceSearcher: InheritanceItemsSearcher?)
 
     public fun execute(): Result? {
         fun postProcess(item: LookupElement): LookupElement {
@@ -72,9 +81,9 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
         val additionalItems = result.additionalItems.map(::postProcess)
         val filter = result.declarationFilter
         return if (filter != null)
-            Result({ filter(it).map(::postProcess) }, additionalItems)
+            Result({ filter(it).map(::postProcess) }, additionalItems, result.inheritanceSearcher)
         else
-            Result(null, additionalItems)
+            Result(null, additionalItems, result.inheritanceSearcher)
     }
 
     private fun executeInternal(): Result? {
@@ -127,8 +136,10 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
         }
 
         val additionalItems = ArrayList<LookupElement>()
+        val inheritanceSearchers = ArrayList<InheritanceItemsSearcher>()
         if (receiver == null) {
-            TypeInstantiationItems(resolutionFacade, bindingContext, visibilityFilter).addToCollection(additionalItems, expectedInfos)
+            TypeInstantiationItems(resolutionFacade, moduleDescriptor, bindingContext, visibilityFilter, searchScope)
+                    .add(additionalItems, inheritanceSearchers, expectedInfos)
 
             StaticMembers(bindingContext, resolutionFacade).addToCollection(additionalItems, expectedInfos, expression, itemsToSkip)
 
@@ -141,7 +152,15 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
             MultipleArgumentsItemProvider(bindingContext, typesWithSmartCasts).addToCollection(additionalItems, expectedInfos, expression)
         }
 
-        return Result(::filterDeclaration, additionalItems)
+        val inheritanceSearcher = if (inheritanceSearchers.isNotEmpty())
+            object : InheritanceItemsSearcher {
+                override fun search(nameFilter: (String) -> Boolean, consumer: (LookupElement) -> Unit) {
+                    inheritanceSearchers.forEach { it.search(nameFilter, consumer) }
+                }
+            }
+        else
+            null
+        return Result(::filterDeclaration, additionalItems, inheritanceSearcher)
     }
 
     private fun calcExpectedInfos(expression: JetExpression): Collection<ExpectedInfo>? {
@@ -289,7 +308,7 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
             val lookupElement = lookupElementForType(jetType) ?: continue
             items.add(lookupElement.addTailAndNameSimilarity(infos))
         }
-        return Result(null, items)
+        return Result(null, items, null)
     }
 
     private fun lookupElementForType(jetType: JetType): LookupElement? {
diff --git a/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt b/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt
index 8d528743593..d284010e2cc 100644
--- a/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt
+++ b/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt
@@ -39,23 +39,95 @@ import org.jetbrains.jet.lang.resolve.BindingContext
 import org.jetbrains.jet.lang.descriptors.PackageFragmentDescriptor
 import org.jetbrains.jet.lang.resolve.java.descriptor.SamConstructorDescriptor
 import org.jetbrains.jet.plugin.caches.resolve.ResolutionFacade
+import org.jetbrains.jet.lang.resolve.DescriptorToSourceUtils
+import com.intellij.psi.PsiClass
+import com.intellij.psi.search.GlobalSearchScope
+import com.intellij.psi.search.searches.ClassInheritorsSearch
+import org.jetbrains.jet.asJava.KotlinLightClass
+import org.jetbrains.jet.lang.types.TypeProjection
+import org.jetbrains.jet.utils.addIfNotNull
+import org.jetbrains.jet.plugin.caches.resolve.JavaResolveExtension
+import org.jetbrains.jet.lang.resolve.java.structure.impl.JavaClassImpl
+import org.jetbrains.jet.asJava.LightClassUtil
+import org.jetbrains.jet.lang.psi.JetClassOrObject
+import org.jetbrains.jet.lang.resolve.PossiblyBareType
+import org.jetbrains.jet.lang.types.JetTypeImpl
+import org.jetbrains.jet.lang.descriptors.annotations.Annotations
+import org.jetbrains.jet.lang.resolve.DescriptorUtils
+import org.jetbrains.jet.lang.resolve.java.mapping.KotlinToJavaTypesMap
+import org.jetbrains.jet.lang.resolve.lazy.ResolveSessionUtils
+import org.jetbrains.jet.lang.descriptors.ModuleDescriptor
+import org.jetbrains.jet.lang.resolve.resolveTopLevelClass
 
-class TypeInstantiationItems(val resolutionFacade: ResolutionFacade, val bindingContext: BindingContext, val visibilityFilter: (DeclarationDescriptor) -> Boolean) {
-    public fun addToCollection(collection: MutableCollection<LookupElement>, expectedInfos: Collection<ExpectedInfo>) {
+class TypeInstantiationItems(
+        val resolutionFacade: ResolutionFacade,
+        val moduleDescriptor: ModuleDescriptor,
+        val bindingContext: BindingContext,
+        val visibilityFilter: (DeclarationDescriptor) -> Boolean,
+        val searchScope: GlobalSearchScope
+) {
+    public fun add(
+            items: MutableCollection<LookupElement>,
+            inheritanceSearchers: MutableCollection<InheritanceItemsSearcher>,
+            expectedInfos: Collection<ExpectedInfo>
+    ) {
         val expectedInfosGrouped: Map<JetType, List<ExpectedInfo>> = expectedInfos.groupBy { it.type.makeNotNullable() }
-        for ((jetType, infos) in expectedInfosGrouped) {
+        for ((type, infos) in expectedInfosGrouped) {
             val tail = mergeTails(infos.map { it.tail })
-            addToCollection(collection, jetType, tail)
+            addToCollection(items, inheritanceSearchers, type, tail)
         }
     }
 
-    private fun addToCollection(collection: MutableCollection<LookupElement>, jetType: JetType, tail: Tail?) {
-        if (KotlinBuiltIns.getInstance().isExactFunctionOrExtensionFunctionType(jetType)) return // do not show "object: ..." for function types
+    private fun addToCollection(
+            items: MutableCollection<LookupElement>,
+            inheritanceSearchers: MutableCollection<InheritanceItemsSearcher>,
+            type: JetType,
+            tail: Tail?
+    ) {
+        if (KotlinBuiltIns.getInstance().isExactFunctionOrExtensionFunctionType(type)) return // do not show "object: ..." for function types
 
-        val classifier = jetType.getConstructor().getDeclarationDescriptor()
+        val classifier = type.getConstructor().getDeclarationDescriptor()
         if (classifier !is ClassDescriptor) return
 
-        addSamConstructorItem(collection, classifier, tail)
+        addSamConstructorItem(items, classifier, tail)
+
+        val typeArgs = type.getArguments()
+        items.addIfNotNull(createTypeInstantiationItem(classifier, typeArgs, tail))
+
+        inheritanceSearchers.addInheritorSearcher(classifier, classifier, typeArgs, tail)
+
+        val javaAnalogFqName = KotlinToJavaTypesMap.getInstance().getKotlinToJavaFqName(DescriptorUtils.getFqNameSafe(classifier))
+        if (javaAnalogFqName != null) {
+            val javaAnalog = moduleDescriptor.resolveTopLevelClass(javaAnalogFqName)
+            if (javaAnalog != null) {
+                inheritanceSearchers.addInheritorSearcher(javaAnalog, classifier, typeArgs, tail)
+            }
+        }
+    }
+
+    private fun MutableCollection<InheritanceItemsSearcher>.addInheritorSearcher(
+            descriptor: ClassDescriptor, kotlinClassDescriptor: ClassDescriptor, typeArgs: List<TypeProjection>, tail: Tail?
+    ) {
+        val declaration = DescriptorToSourceUtils.descriptorToDeclaration(descriptor)
+        val psiClass: PsiClass = when (declaration) {
+            is PsiClass -> declaration
+            is JetClassOrObject -> LightClassUtil.getPsiClass(declaration) ?: return
+            else -> return
+        }
+        if (declaration.getContainingFile().getVirtualFile() == null) return //TODO!
+        add(InheritanceSearcher(psiClass, kotlinClassDescriptor, typeArgs, tail))
+    }
+
+    private fun createTypeInstantiationItem(
+            classifier: ClassDescriptor,
+            typeArgs: List<TypeProjection?>,
+            tail: Tail?
+    ): LookupElement? {
+        var lookupElement = LookupElementFactory.DEFAULT.createLookupElement(classifier, resolutionFacade, bindingContext)
+
+        if (classifier.getKind() == ClassKind.OBJECT) {
+            return lookupElement.addTail(tail)
+        }
 
         val isAbstract = classifier.getModality() == Modality.ABSTRACT
         val allConstructors = classifier.getConstructors()
@@ -65,14 +137,11 @@ class TypeInstantiationItems(val resolutionFacade: ResolutionFacade, val binding
             else
                 visibilityFilter(it)
         }
-        if (allConstructors.isNotEmpty() && visibleConstructors.isEmpty()) return
-
-        var lookupElement = LookupElementFactory.DEFAULT.createLookupElement(classifier, resolutionFacade, bindingContext)
+        if (allConstructors.isNotEmpty() && visibleConstructors.isEmpty()) return null
 
         var lookupString = lookupElement.getLookupString()
         var allLookupStrings = setOf(lookupString)
 
-        val typeArgs = jetType.getArguments()
         var itemText = lookupString + DescriptorRenderer.SHORT_NAMES_IN_TYPES.renderTypeArguments(typeArgs)
         var signatureText: String? = null
 
@@ -140,9 +209,11 @@ class TypeInstantiationItems(val resolutionFacade: ResolutionFacade, val binding
                 getDelegate().renderElement(presentation)
                 presentation.setItemText(itemText)
 
+                presentation.clearTail()
                 if (signatureText != null) {
-                    presentation.prependTailText(signatureText!!, false)
+                    presentation.appendTailText(signatureText!!, false)
                 }
+                presentation.appendTailText(" (" + DescriptorUtils.getFqName(classifier.getContainingDeclaration()) + ")", true)
             }
 
             override fun handleInsert(context: InsertionContext) {
@@ -150,7 +221,7 @@ class TypeInstantiationItems(val resolutionFacade: ResolutionFacade, val binding
             }
         }
 
-        collection.add(lookupElement.addTail(tail))
+        return lookupElement.addTail(tail)
     }
 
     private fun addSamConstructorItem(collection: MutableCollection<LookupElement>, `class`: ClassDescriptor, tail: Tail?) {
@@ -170,4 +241,44 @@ class TypeInstantiationItems(val resolutionFacade: ResolutionFacade, val binding
             collection.add(lookupElement)
         }
     }
+
+    private inner class InheritanceSearcher(
+            val psiClass: PsiClass,
+            val classDescriptor: ClassDescriptor,
+            val typeArgs: List<TypeProjection?>,
+            val tail: Tail?) : InheritanceItemsSearcher {
+
+        private val typeConstructor = classDescriptor.getTypeConstructor()
+        private val baseHasTypeArgs = typeConstructor.getParameters().isNotEmpty()
+        private val expectedType = JetTypeImpl(Annotations.EMPTY, typeConstructor, false, typeArgs, classDescriptor.getMemberScope(typeArgs))
+
+        override fun search(nameFilter: (String) -> Boolean, consumer: (LookupElement) -> Unit) {
+            val parameters = ClassInheritorsSearch.SearchParameters(psiClass, searchScope, true, true, false, nameFilter)
+            for (inheritor in ClassInheritorsSearch.search(parameters)) {
+                val descriptor = if (inheritor is KotlinLightClass) {
+                    val origin = inheritor.origin ?: continue
+                    resolutionFacade.resolveToDescriptor(origin)
+                }
+                else {
+                    resolutionFacade.get(JavaResolveExtension)(inheritor).first.resolveClass(JavaClassImpl(inheritor))
+                }  as? ClassDescriptor ?: continue
+                if (!visibilityFilter(descriptor)) continue
+
+                val hasTypeArgs = descriptor.getTypeConstructor().getParameters().isNotEmpty()
+                val resultingType = if (hasTypeArgs) {
+                    val reconstructionResult = PossiblyBareType.bare(descriptor.getTypeConstructor(), false).reconstruct(expectedType)
+                    reconstructionResult.getResultingType() ?: continue
+                }
+                else {
+                    val type = descriptor.getDefaultType()
+                    // check if derived type matches type arguments for base
+                    if (baseHasTypeArgs && !type.isSubtypeOf(expectedType)) continue
+                    type
+                }
+
+                val lookupElement = createTypeInstantiationItem(descriptor, resultingType.getArguments(), tail) ?: continue
+                consumer(lookupElement.assignSmartCompletionPriority(SmartCompletionItemPriority.INHERITOR_INSTANTIATION))
+            }
+        }
+    }
 }
diff --git a/idea/src/org/jetbrains/jet/plugin/completion/smart/Utils.kt b/idea/src/org/jetbrains/jet/plugin/completion/smart/Utils.kt
index 3160312d965..ecd1e1f0e94 100644
--- a/idea/src/org/jetbrains/jet/plugin/completion/smart/Utils.kt
+++ b/idea/src/org/jetbrains/jet/plugin/completion/smart/Utils.kt
@@ -225,6 +225,7 @@ enum class SmartCompletionItemPriority {
     LAMBDA
     FUNCTION_REFERENCE
     NULL
+    INHERITOR_INSTANTIATION
 }
 
 val SMART_COMPLETION_ITEM_PRIORITY_KEY = Key<SmartCompletionItemPriority>("SMART_COMPLETION_ITEM_PRIORITY_KEY")
diff --git a/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt b/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt
index c5a3621dfa7..a6b4b03013c 100644
--- a/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt
+++ b/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt
@@ -1,3 +1,3 @@
 val c: java.io.Closeable = <caret>
 
-//ELEMENT: object
+//ELEMENT_TEXT: "object: Closeable{...}"
diff --git a/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt.after b/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt.after
index dd45d717dbb..94e8d5e60da 100644
--- a/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt.after
+++ b/idea/testData/completion/handlers/smart/AnonymousObjectInsertsImport.kt.after
@@ -6,4 +6,4 @@ val c: java.io.Closeable = object: Closeable {
     }
 }
 
-//ELEMENT: object
+//ELEMENT_TEXT: "object: Closeable{...}"
diff --git a/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt b/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt
index 89f096e66de..fc846187885 100644
--- a/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt
+++ b/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt
@@ -1,3 +1,6 @@
 import java.util.Date
 
 var a : Date = <caret>
+
+// ELEMENT: Date
+// TAIL_TEXT: "(...) (java.util)"
diff --git a/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt.after b/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt.after
index 930016dcc56..1521502b9d4 100644
--- a/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt.after
+++ b/idea/testData/completion/handlers/smart/ConstructorForJavaClass.kt.after
@@ -1,3 +1,6 @@
 import java.util.Date
 
 var a : Date = Date(<caret>)
+
+// ELEMENT: Date
+// TAIL_TEXT: "(...) (java.util)"
diff --git a/idea/testData/completion/handlers/smart/SAMExpected1.kt b/idea/testData/completion/handlers/smart/SAMExpected1.kt
index 2165af6730a..fdd76379b31 100644
--- a/idea/testData/completion/handlers/smart/SAMExpected1.kt
+++ b/idea/testData/completion/handlers/smart/SAMExpected1.kt
@@ -1,3 +1,4 @@
 var a : Runnable = <caret>
 
-// ELEMENT: Runnable
+// ELEMENT_TEXT: Runnable
+// TAIL_TEXT: "()"
diff --git a/idea/testData/completion/handlers/smart/SAMExpected1.kt.after b/idea/testData/completion/handlers/smart/SAMExpected1.kt.after
index 60e6188a3fe..599e5d9546b 100644
--- a/idea/testData/completion/handlers/smart/SAMExpected1.kt.after
+++ b/idea/testData/completion/handlers/smart/SAMExpected1.kt.after
@@ -1,3 +1,4 @@
 var a : Runnable = Runnable { <caret> }
 
-// ELEMENT: Runnable
+// ELEMENT_TEXT: Runnable
+// TAIL_TEXT: "()"
diff --git a/idea/testData/completion/smart/ConstructorForGenericJavaClass.kt b/idea/testData/completion/smart/ConstructorForGenericJavaClass.kt
new file mode 100644
index 00000000000..800440d0b37
--- /dev/null
+++ b/idea/testData/completion/smart/ConstructorForGenericJavaClass.kt
@@ -0,0 +1,5 @@
+import java.util.ArrayList
+
+var a : ArrayList<String> = <caret>
+
+// EXIST: { lookupString: "ArrayList", itemText: "ArrayList<String>", tailText: "(...) (java.util)" }
diff --git a/idea/testData/completion/smart/ConstructorForGenericJavaClass.kt.todo b/idea/testData/completion/smart/ConstructorForGenericJavaClass.kt.todo
deleted file mode 100644
index 71eb5f66616..00000000000
--- a/idea/testData/completion/smart/ConstructorForGenericJavaClass.kt.todo
+++ /dev/null
@@ -1,5 +0,0 @@
-import java.util.ArrayList
-
-var a : ArrayList<String> = <caret>
-
-// EXIST: ArrayList@ArrayList<String>()
diff --git a/idea/testData/completion/smart/Inheritors1.kt b/idea/testData/completion/smart/Inheritors1.kt
new file mode 100644
index 00000000000..081a40088c2
--- /dev/null
+++ b/idea/testData/completion/smart/Inheritors1.kt
@@ -0,0 +1,8 @@
+import java.io.InputStream
+
+fun foo(): InputStream {
+    return <caret>
+}
+
+// EXIST: ByteArrayInputStream
+// EXIST: FileInputStream
diff --git a/idea/testData/completion/smart/Inheritors2.kt b/idea/testData/completion/smart/Inheritors2.kt
new file mode 100644
index 00000000000..c6dfb12bcdb
--- /dev/null
+++ b/idea/testData/completion/smart/Inheritors2.kt
@@ -0,0 +1,5 @@
+fun foo(): List<String> {
+    return <caret>
+}
+
+// EXIST: { lookupString: "ArrayList", itemText: "ArrayList<String>", tailText: "(...) (java.util)" }
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors1/GenericInheritors1.kt b/idea/testData/completion/smartMultiFile/GenericInheritors1/GenericInheritors1.kt
new file mode 100644
index 00000000000..80a4dd91276
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors1/GenericInheritors1.kt
@@ -0,0 +1,15 @@
+import p.*
+
+fun foo(): KotlinTrait<I1, I2> {
+    return <caret>
+}
+
+// EXIST: { lookupString: "object", itemText: "object: KotlinTrait<I1, I2>{...}" }
+// EXIST: { lookupString: "KotlinInheritor1", itemText: "KotlinInheritor1<I1>", tailText: "() (p)" }
+// EXIST: { lookupString: "KotlinInheritor2", itemText: "KotlinInheritor2", tailText: "() (p)" }
+// ABSENT: KotlinInheritor3
+// EXIST: { lookupString: "object", itemText: "object: KotlinInheritor4<I1, I2>(){...}" }
+// ABSENT: KotlinInheritor5
+// EXIST: { lookupString: "KotlinInheritor6", itemText: "KotlinInheritor6<I1, out Any?, out I3>", tailText: "() (p)" }
+// EXIST: { lookupString: "JavaInheritor1", itemText: "JavaInheritor1", tailText: "() (<root>)" }
+// ABSENT: JavaInheritor2
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors1/JavaInheritors.java b/idea/testData/completion/smartMultiFile/GenericInheritors1/JavaInheritors.java
new file mode 100644
index 00000000000..045668d12f8
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors1/JavaInheritors.java
@@ -0,0 +1,6 @@
+import p.*
+
+class JavaInheritor1 implements KotlinTrait<I1, I2>{}
+
+// is not suitable because type arguments do not match
+class JavaInheritor2 implements KotlinTrait<I1, I3>{}
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors1/KotlinInheritors.kt b/idea/testData/completion/smartMultiFile/GenericInheritors1/KotlinInheritors.kt
new file mode 100644
index 00000000000..12efb662ecb
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors1/KotlinInheritors.kt
@@ -0,0 +1,23 @@
+package p
+
+trait I1
+trait I2
+trait I3
+
+trait KotlinTrait<T1, T2>
+
+open class KotlinInheritor1<T> : KotlinTrait<T, I2>
+
+class KotlinInheritor2 : KotlinInheritor1<I1>()
+
+// is not suitable because type arguments do not match
+class KotlinInheritor3 : KotlinInheritor1<Any>()
+
+abstract class KotlinInheritor4<T, V> : KotlinTrait<T, V>
+
+// is not suitable because type arguments do not match
+class KotlinInheritor5 : KotlinTrait<Char, I2>
+
+class KotlinInheritor6<T1, T2, T3 : I3> : KotlinTrait<T1, I2>
+
+// ALLOW_AST_ACCESS
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors2/GenericInheritors2.kt b/idea/testData/completion/smartMultiFile/GenericInheritors2/GenericInheritors2.kt
new file mode 100644
index 00000000000..219f665fddc
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors2/GenericInheritors2.kt
@@ -0,0 +1,8 @@
+import p.*
+
+fun foo(): KotlinTrait<I1, I1> {
+    return <caret>
+}
+
+// EXIST: { lookupString: "object", itemText: "object: KotlinTrait<I1, I1>{...}" }
+// EXIST: { lookupString: "KotlinInheritor", itemText: "KotlinInheritor<I1>", tailText: "() (p)" }
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors2/KotlinInheritors.kt b/idea/testData/completion/smartMultiFile/GenericInheritors2/KotlinInheritors.kt
new file mode 100644
index 00000000000..7eeddf70d97
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors2/KotlinInheritors.kt
@@ -0,0 +1,11 @@
+package p
+
+trait I1
+trait I2
+trait I3
+
+trait KotlinTrait<T1, T2>
+
+class KotlinInheritor<T> : KotlinTrait<T, T>
+
+// ALLOW_AST_ACCESS
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors3/GenericInheritors3.kt b/idea/testData/completion/smartMultiFile/GenericInheritors3/GenericInheritors3.kt
new file mode 100644
index 00000000000..f0712e996b0
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors3/GenericInheritors3.kt
@@ -0,0 +1,8 @@
+import p.*
+
+fun foo(): KotlinTrait<I1, I2> {
+    return <caret>
+}
+
+// EXIST: { lookupString: "object", itemText: "object: KotlinTrait<I1, I2>{...}" }
+// ABSENT: KotlinInheritor
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors3/KotlinInheritors.kt b/idea/testData/completion/smartMultiFile/GenericInheritors3/KotlinInheritors.kt
new file mode 100644
index 00000000000..7eeddf70d97
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors3/KotlinInheritors.kt
@@ -0,0 +1,11 @@
+package p
+
+trait I1
+trait I2
+trait I3
+
+trait KotlinTrait<T1, T2>
+
+class KotlinInheritor<T> : KotlinTrait<T, T>
+
+// ALLOW_AST_ACCESS
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors4/GenericInheritors4.kt b/idea/testData/completion/smartMultiFile/GenericInheritors4/GenericInheritors4.kt
new file mode 100644
index 00000000000..dc3f5e7e3e9
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors4/GenericInheritors4.kt
@@ -0,0 +1,8 @@
+import p.*
+
+fun foo(): KotlinTrait<I1<I2>> {
+    return <caret>
+}
+
+// EXIST: { lookupString: "object", itemText: "object: KotlinTrait<I1<I2>>{...}" }
+// EXIST: { lookupString: "KotlinInheritor", itemText: "KotlinInheritor<I2>", tailText: "() (p)" }
diff --git a/idea/testData/completion/smartMultiFile/GenericInheritors4/KotlinInheritors.kt b/idea/testData/completion/smartMultiFile/GenericInheritors4/KotlinInheritors.kt
new file mode 100644
index 00000000000..bf3ef9ee514
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/GenericInheritors4/KotlinInheritors.kt
@@ -0,0 +1,10 @@
+package p
+
+trait I1<T>
+trait I2
+
+trait KotlinTrait<T>
+
+class KotlinInheritor<T> : KotlinTrait<I1<T>>
+
+// ALLOW_AST_ACCESS
diff --git a/idea/testData/completion/smartMultiFile/Inheritors/Inheritors.kt b/idea/testData/completion/smartMultiFile/Inheritors/Inheritors.kt
new file mode 100644
index 00000000000..fa6053029e7
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/Inheritors/Inheritors.kt
@@ -0,0 +1,15 @@
+package p1
+
+fun foo(): p2.KotlinTrait {
+    return <caret>
+}
+
+// EXIST: { lookupString: "object", itemText: "object: KotlinTrait{...}" }
+// EXIST: { lookupString: "KotlinInheritor1", itemText: "KotlinInheritor1", tailText: "() (p2)" }
+// EXIST: { lookupString: "KotlinInheritor2", itemText: "KotlinInheritor2", tailText: "(s: String) (p2)" }
+// EXIST: { lookupString: "object", itemText: "object: KotlinInheritor3(){...}" }
+// ABSENT: PrivateInheritor
+// EXIST: { lookupString: "object", itemText: "object: JavaInheritor1(){...}" }
+// EXIST: { lookupString: "JavaInheritor2", itemText: "JavaInheritor2", tailText: "(...) (<root>)" }
+// ABSENT: JavaInheritor3
+// EXIST: { lookupString: "ObjectInheritor", itemText: "ObjectInheritor", tailText: " (p2)" }
diff --git a/idea/testData/completion/smartMultiFile/Inheritors/JavaInheritors.java b/idea/testData/completion/smartMultiFile/Inheritors/JavaInheritors.java
new file mode 100644
index 00000000000..038038f0fcb
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/Inheritors/JavaInheritors.java
@@ -0,0 +1,16 @@
+import p2.KotlinTrait
+
+public abstract class JavaInheritor1 implements KotlinTrait {
+}
+
+public class JavaInheritor2 extends JavaInheritor1 {
+    public JavaInheritor2() {
+    }
+
+    public JavaInheritor2(int p) {
+    }
+}
+
+// not visible - it's package local
+class JavaInheritor3 extends KotlinTrait {}
+
diff --git a/idea/testData/completion/smartMultiFile/Inheritors/KotlinInheritors.kt b/idea/testData/completion/smartMultiFile/Inheritors/KotlinInheritors.kt
new file mode 100644
index 00000000000..80b28599d6e
--- /dev/null
+++ b/idea/testData/completion/smartMultiFile/Inheritors/KotlinInheritors.kt
@@ -0,0 +1,17 @@
+package p2
+
+trait KotlinTrait
+
+open class KotlinInheritor1 : KotlinTrait
+
+class KotlinInheritor2(s: String) : KotlinInheritor1()
+
+abstract class KotlinInheritor3 : KotlinTrait
+
+class C {
+    private class PrivateInheritor : KotlinTrait
+}
+
+object ObjectInheritor : KotlinTrait
+
+// ALLOW_AST_ACCESS
diff --git a/idea/tests/org/jetbrains/jet/completion/JvmSmartCompletionTestGenerated.java b/idea/tests/org/jetbrains/jet/completion/JvmSmartCompletionTestGenerated.java
index 4881c0800bb..2e8732d5052 100644
--- a/idea/tests/org/jetbrains/jet/completion/JvmSmartCompletionTestGenerated.java
+++ b/idea/tests/org/jetbrains/jet/completion/JvmSmartCompletionTestGenerated.java
@@ -19,7 +19,6 @@ package org.jetbrains.jet.completion;
 import com.intellij.testFramework.TestDataPath;
 import org.jetbrains.jet.JUnit3RunnerWithInners;
 import org.jetbrains.jet.JetTestUtils;
-import org.jetbrains.jet.test.InnerTestClasses;
 import org.jetbrains.jet.test.TestMetadata;
 import org.junit.runner.RunWith;
 
@@ -168,6 +167,12 @@ public class JvmSmartCompletionTestGenerated extends AbstractJvmSmartCompletionT
         doTest(fileName);
     }
 
+    @TestMetadata("ConstructorForGenericJavaClass.kt")
+    public void testConstructorForGenericJavaClass() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smart/ConstructorForGenericJavaClass.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("ConstructorForGenericType.kt")
     public void testConstructorForGenericType() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smart/ConstructorForGenericType.kt");
@@ -384,6 +389,18 @@ public class JvmSmartCompletionTestGenerated extends AbstractJvmSmartCompletionT
         doTest(fileName);
     }
 
+    @TestMetadata("Inheritors1.kt")
+    public void testInheritors1() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smart/Inheritors1.kt");
+        doTest(fileName);
+    }
+
+    @TestMetadata("Inheritors2.kt")
+    public void testInheritors2() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smart/Inheritors2.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("InsideIdentifier.kt")
     public void testInsideIdentifier() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smart/InsideIdentifier.kt");
diff --git a/idea/tests/org/jetbrains/jet/completion/MultiFileSmartCompletionTestGenerated.java b/idea/tests/org/jetbrains/jet/completion/MultiFileSmartCompletionTestGenerated.java
index 7e6aa4277e6..ddb3b5ea691 100644
--- a/idea/tests/org/jetbrains/jet/completion/MultiFileSmartCompletionTestGenerated.java
+++ b/idea/tests/org/jetbrains/jet/completion/MultiFileSmartCompletionTestGenerated.java
@@ -42,6 +42,36 @@ public class MultiFileSmartCompletionTestGenerated extends AbstractMultiFileSmar
         doTest(fileName);
     }
 
+    @TestMetadata("GenericInheritors1")
+    public void testGenericInheritors1() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smartMultiFile/GenericInheritors1/");
+        doTest(fileName);
+    }
+
+    @TestMetadata("GenericInheritors2")
+    public void testGenericInheritors2() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smartMultiFile/GenericInheritors2/");
+        doTest(fileName);
+    }
+
+    @TestMetadata("GenericInheritors3")
+    public void testGenericInheritors3() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smartMultiFile/GenericInheritors3/");
+        doTest(fileName);
+    }
+
+    @TestMetadata("GenericInheritors4")
+    public void testGenericInheritors4() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smartMultiFile/GenericInheritors4/");
+        doTest(fileName);
+    }
+
+    @TestMetadata("Inheritors")
+    public void testInheritors() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smartMultiFile/Inheritors/");
+        doTest(fileName);
+    }
+
     @TestMetadata("JavaStaticMethodArgument")
     public void testJavaStaticMethodArgument() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/testData/completion/smartMultiFile/JavaStaticMethodArgument/");
diff --git a/idea/tests/org/jetbrains/jet/plugin/KotlinCompletionTestCase.java b/idea/tests/org/jetbrains/jet/plugin/KotlinCompletionTestCase.java
index 6a8f36617a2..ad966d21496 100644
--- a/idea/tests/org/jetbrains/jet/plugin/KotlinCompletionTestCase.java
+++ b/idea/tests/org/jetbrains/jet/plugin/KotlinCompletionTestCase.java
@@ -18,7 +18,6 @@ package org.jetbrains.jet.plugin;
 
 import com.intellij.codeInsight.completion.CompletionTestCase;
 import com.intellij.openapi.vfs.newvfs.impl.VfsRootAccess;
-import com.intellij.openapi.vfs.newvfs.impl.VirtualDirectoryImpl;
 import org.jetbrains.jet.JetTestCaseBuilder;
 
 abstract public class KotlinCompletionTestCase extends CompletionTestCase {