Ordering items in smart completion for 'it'

idea/src/org/jetbrains/jet/plugin/completion/smart/SmartCompletion.kt

@@ -116,7 +116,7 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
                         else -> ExpectedInfoClassification.NOT_MATCHES
                     }
                 }
-                result.addLookupElements(expectedInfos, classifier, { createLookupElement(descriptor, resolveSession) })
+                result.addLookupElements(expectedInfos, classifier, { createLookupElement(descriptor, resolveSession, bindingContext) })
 
                 if (receiver == null) {
                     toFunctionReferenceLookupElement(descriptor, functionExpectedInfos)?.let { result.add(it) }
@@ -127,7 +127,7 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
 
         val additionalItems = ArrayList<LookupElement>()
         if (receiver == null) {
-            TypeInstantiationItems(resolveSession, visibilityFilter).addToCollection(additionalItems, expectedInfos)
+            TypeInstantiationItems(resolveSession, bindingContext, visibilityFilter).addToCollection(additionalItems, expectedInfos)
 
             StaticMembers(bindingContext, resolveSession).addToCollection(additionalItems, expectedInfos, expression, itemsToSkip)
 
@@ -236,7 +236,7 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
             val matchedExpectedInfos = functionExpectedInfos.filter { functionType.isSubtypeOf(it.type) }
             if (matchedExpectedInfos.isEmpty()) return null
 
-            var lookupElement = createLookupElement(descriptor, resolveSession)
+            var lookupElement = createLookupElement(descriptor, resolveSession, bindingContext)
             val text = "::" + (if (descriptor is ConstructorDescriptor) descriptor.getContainingDeclaration().getName() else descriptor.getName())
             lookupElement = object: LookupElementDecorator<LookupElement>(lookupElement) {
                 override fun getLookupString() = text
@@ -293,7 +293,7 @@ class SmartCompletion(val expression: JetSimpleNameExpression,
         if (jetType.isError()) return null
         val classifier = jetType.getConstructor().getDeclarationDescriptor() ?: return null
 
-        val lookupElement = createLookupElement(classifier, resolveSession)
+        val lookupElement = createLookupElement(classifier, resolveSession, bindingContext)
         val lookupString = lookupElement.getLookupString()
 
         val typeArgs = jetType.getArguments()

idea/src/org/jetbrains/jet/plugin/completion/smart/StaticMembers.kt

@@ -107,7 +107,7 @@ class StaticMembers(val bindingContext: BindingContext, val resolveSession: Reso
     }
 
     private fun createLookupElement(memberDescriptor: DeclarationDescriptor, classDescriptor: ClassDescriptor): LookupElement {
-        val lookupElement = createLookupElement(memberDescriptor, resolveSession)
+        val lookupElement = createLookupElement(memberDescriptor, resolveSession, bindingContext)
         val qualifierPresentation = classDescriptor.getName().asString()
         val lookupString = qualifierPresentation + "." + lookupElement.getLookupString()
         val qualifierText = qualifiedNameForSourceCode(classDescriptor)

idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt

@@ -36,8 +36,9 @@ import org.jetbrains.jet.lang.descriptors.DeclarationDescriptor
 import org.jetbrains.jet.lang.descriptors.Visibilities
 import org.jetbrains.jet.plugin.util.makeNotNullable
 import org.jetbrains.jet.plugin.util.IdeDescriptorRenderers
+import org.jetbrains.jet.lang.resolve.BindingContext
 
-class TypeInstantiationItems(val resolveSession: ResolveSessionForBodies, val visibilityFilter: (DeclarationDescriptor) -> Boolean) {
+class TypeInstantiationItems(val resolveSession: ResolveSessionForBodies, val bindingContext: BindingContext, val visibilityFilter: (DeclarationDescriptor) -> Boolean) {
     public fun addToCollection(collection: MutableCollection<LookupElement>, expectedInfos: Collection<ExpectedInfo>) {
         val expectedInfosGrouped: Map<JetType, List<ExpectedInfo>> = expectedInfos.groupBy { it.type.makeNotNullable() }
         for ((jetType, infos) in expectedInfosGrouped) {
@@ -62,7 +63,7 @@ class TypeInstantiationItems(val resolveSession: ResolveSessionForBodies, val vi
         }
         if (allConstructors.isNotEmpty() && visibleConstructors.isEmpty()) return
 
-        var lookupElement = createLookupElement(classifier, resolveSession)
+        var lookupElement = createLookupElement(classifier, resolveSession, bindingContext)
 
         var lookupString = lookupElement.getLookupString()
 

idea/src/org/jetbrains/jet/plugin/completion/smart/Utils.kt

@@ -37,6 +37,8 @@ import org.jetbrains.jet.plugin.completion.handlers.WithTailInsertHandler
 import org.jetbrains.jet.lang.descriptors.ConstructorDescriptor
 import org.jetbrains.jet.lang.descriptors.ClassifierDescriptor
 import com.intellij.openapi.util.Key
+import org.jetbrains.jet.lang.descriptors.ValueParameterDescriptor
+import org.jetbrains.jet.lang.resolve.BindingContext
 
 class ArtificialElementInsertHandler(
         val textBeforeCaret: String, val textAfterCaret: String, val shortenRefs: Boolean) : InsertHandler<LookupElement>{
@@ -184,9 +186,18 @@ fun functionType(function: FunctionDescriptor): JetType? {
                                                         function.getReturnType() ?: return null)
 }
 
-fun createLookupElement(descriptor: DeclarationDescriptor, resolveSession: ResolveSessionForBodies): LookupElement {
+fun createLookupElement(descriptor: DeclarationDescriptor, resolveSession: ResolveSessionForBodies, bindingContext: BindingContext): LookupElement {
-    val element = KotlinLookupElementFactory.createLookupElement(resolveSession, descriptor)
+    var element = KotlinLookupElementFactory.createLookupElement(resolveSession, descriptor)
-    return if (descriptor is FunctionDescriptor && descriptor.getValueParameters().isNotEmpty()) element.keepOldArgumentListOnTab() else element
+
+    if (descriptor is FunctionDescriptor && descriptor.getValueParameters().isNotEmpty()) {
+        element = element.keepOldArgumentListOnTab()
+    }
+
+    if (descriptor is ValueParameterDescriptor && bindingContext[BindingContext.AUTO_CREATED_IT, descriptor]) {
+        element = element.assignSmartCompletionPriority(SmartCompletionItemPriority.IT)
+    }
+
+    return element
 }
 
 fun JetType.isSubtypeOf(expectedType: JetType) = !isError() && JetTypeChecker.DEFAULT.isSubtypeOf(this, expectedType)
@@ -197,7 +208,7 @@ fun <T : Any> T?.toSet(): Set<T> = if (this != null) setOf(this) else setOf()
 fun String?.isNullOrEmpty() = this == null || this.isEmpty()
 
 enum class SmartCompletionItemPriority {
-    /*IT*/ //TODO
+    IT
     TRUE
     FALSE
     THIS

idea/testData/completion/weighers/smart/It.kt

@@ -0,0 +1,13 @@
+fun foo(xx: String){}
+
+fun bar(handler: (String) -> Unit){}
+
+fun f() {
+    val v = ""
+    val xx = ""
+    bar { foo(<caret>) }
+}
+
+// ORDER: xx
+// ORDER: it
+// ORDER: v