Smart completion for bound callable references

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/BasicCompletionSession.kt

@@ -144,7 +144,7 @@ class BasicCompletionSession(
         var sorter = super.createSorter()
 
         if (smartCompletion != null) {
-            val smartCompletionInBasicWeigher = SmartCompletionInBasicWeigher(smartCompletion, callTypeAndReceiver.callType, resolutionFacade)
+            val smartCompletionInBasicWeigher = SmartCompletionInBasicWeigher(smartCompletion, callTypeAndReceiver, resolutionFacade, bindingContext)
             sorter = sorter.weighBefore(KindWeigher.toString(),
                                         smartCompletionInBasicWeigher,
                                         SmartCompletionPriorityWeigher,

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/Weighers.kt

@@ -31,7 +31,9 @@ import org.jetbrains.kotlin.idea.core.completion.DeclarationLookupObject
 import org.jetbrains.kotlin.idea.core.completion.PackageLookupObject
 import org.jetbrains.kotlin.idea.resolve.ResolutionFacade
 import org.jetbrains.kotlin.idea.util.CallType
+import org.jetbrains.kotlin.idea.util.CallTypeAndReceiver
 import org.jetbrains.kotlin.idea.util.toFuzzyType
+import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.descriptorUtil.parentsWithSelf
 import org.jetbrains.kotlin.resolve.findOriginalTopMostOverriddenDescriptors
 import org.jetbrains.kotlin.types.typeUtil.isNothing
@@ -211,8 +213,9 @@ object PreferMatchingItemWeigher : LookupElementWeigher("kotlin.preferMatching",
 
 class SmartCompletionInBasicWeigher(
         private val smartCompletion: SmartCompletion,
-        private val callType: CallType<*>,
-        private val resolutionFacade: ResolutionFacade
+        private val callTypeAndReceiver: CallTypeAndReceiver<*, *>,
+        private val resolutionFacade: ResolutionFacade,
+        private val bindingContext: BindingContext
 ) : LookupElementWeigher("kotlin.smartInBasic", true, false) {
 
     companion object {
@@ -259,7 +262,7 @@ class SmartCompletionInBasicWeigher(
         val (fuzzyTypes, name) = when (o) {
             is DeclarationLookupObject -> {
                 val descriptor = o.descriptor ?: return NO_MATCH_WEIGHT
-                descriptor.fuzzyTypesForSmartCompletion(smartCastCalculator, callType, resolutionFacade) to descriptor.name
+                descriptor.fuzzyTypesForSmartCompletion(smartCastCalculator, callTypeAndReceiver, resolutionFacade, bindingContext) to descriptor.name
             }
 
             is ThisItemLookupObject -> smartCastCalculator.types(o.receiverParameter).map { it.toFuzzyType(emptyList()) } to null

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/smart/SmartCompletion.kt

@@ -162,7 +162,7 @@ class SmartCompletion(
         if (descriptor in descriptorsToSkip) return emptyList()
 
         val result = SmartList<LookupElement>()
-        val types = descriptor.fuzzyTypesForSmartCompletion(smartCastCalculator, callTypeAndReceiver.callType, resolutionFacade)
+        val types = descriptor.fuzzyTypesForSmartCompletion(smartCastCalculator, callTypeAndReceiver, resolutionFacade, bindingContext)
         val infoMatcher = { expectedInfo: ExpectedInfo -> types.matchExpectedInfo(expectedInfo) }
 
         result.addLookupElements(descriptor, expectedInfos, infoMatcher, noNameSimilarityForReturnItself = callTypeAndReceiver is CallTypeAndReceiver.DEFAULT) { descriptor ->
@@ -329,7 +329,7 @@ class SmartCompletion(
         if (callableTypeExpectedInfo.isEmpty()) return
 
         fun toLookupElement(descriptor: CallableDescriptor): LookupElement? {
-            val callableReferenceType = descriptor.callableReferenceType(resolutionFacade) ?: return null
+            val callableReferenceType = descriptor.callableReferenceType(resolutionFacade, null) ?: return null
 
             val matchedExpectedInfos = callableTypeExpectedInfo.filter { it.matchingSubstitutor(callableReferenceType) != null }
             if (matchedExpectedInfos.isEmpty()) return null

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/smart/Utils.kt

@@ -33,6 +33,7 @@ import org.jetbrains.kotlin.idea.completion.suppressAutoInsertion
 import org.jetbrains.kotlin.idea.core.*
 import org.jetbrains.kotlin.idea.resolve.ResolutionFacade
 import org.jetbrains.kotlin.idea.util.*
+import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.PossiblyBareType
 import org.jetbrains.kotlin.resolve.callableReferences.createKCallableTypeForReference
 import org.jetbrains.kotlin.types.TypeSubstitutor
@@ -248,14 +249,12 @@ private fun MutableCollection<LookupElement>.addLookupElementsForNullable(factor
     }
 }
 
-fun CallableDescriptor.callableReferenceType(resolutionFacade: ResolutionFacade): FuzzyType? {
+fun CallableDescriptor.callableReferenceType(resolutionFacade: ResolutionFacade, lhs: DoubleColonLHS?): FuzzyType? {
     if (!CallType.CALLABLE_REFERENCE.descriptorKindFilter.accepts(this)) return null // not supported by callable references
 
     return createKCallableTypeForReference(
             this,
-            (dispatchReceiverParameter?.type ?: extensionReceiverParameter?.type)?.let {
-                DoubleColonLHS.Type(it, PossiblyBareType.type(it))
-            },
+            lhs,
             resolutionFacade.getFrontendService(ReflectionTypes::class.java),
             resolutionFacade.moduleDescriptor
     )?.toFuzzyType(emptyList())
@@ -290,11 +289,13 @@ fun LookupElement.assignSmartCompletionPriority(priority: SmartCompletionItemPri
 
 fun DeclarationDescriptor.fuzzyTypesForSmartCompletion(
         smartCastCalculator: SmartCastCalculator,
-        callType: CallType<*>,
-        resolutionFacade: ResolutionFacade
+        callTypeAndReceiver: CallTypeAndReceiver<*, *>,
+        resolutionFacade: ResolutionFacade,
+        bindingContext: BindingContext
 ): Collection<FuzzyType> {
-    if (callType == CallType.CALLABLE_REFERENCE) {
-        return (this as? CallableDescriptor)?.callableReferenceType(resolutionFacade).singletonOrEmptyList()
+    if (callTypeAndReceiver is CallTypeAndReceiver.CALLABLE_REFERENCE) {
+        val lhs = callTypeAndReceiver.receiver?.let { bindingContext[BindingContext.DOUBLE_COLON_LHS, it] }
+        return (this as? CallableDescriptor)?.callableReferenceType(resolutionFacade, lhs).singletonOrEmptyList()
     }
 
     if (this is CallableDescriptor) {

idea/idea-completion/testData/smart/callableReference/ExpressionQualifier.kt

@@ -0,0 +1,27 @@
+class C {
+    fun xf0(s: String){}
+    fun xf1(){}
+    fun xf1(s: String){}
+    fun xf2(i: Int){}
+}
+
+fun C.xfe0(s: String){}
+fun C.xfe1(){}
+fun C.xfe1(s: String){}
+fun C.xfe2(i: Int){}
+
+fun Any.anyF(s: String){}
+fun String.stringF(s: String){}
+
+fun foo(p: (String) -> Unit){}
+
+fun bar(c: C) {
+    foo(c::<caret>)
+}
+
+// EXIST: { lookupString:"xf0", itemText:"xf0", tailText: "(s: String)", typeText: "Unit" }
+// EXIST: { lookupString:"xf1", itemText:"xf1", tailText: "(s: String)", typeText: "Unit" }
+// EXIST: { lookupString:"xfe0", itemText:"xfe0", tailText: "(s: String) for C in <root>", typeText: "Unit" }
+// EXIST: { lookupString:"xfe1", itemText:"xfe1", tailText: "(s: String) for C in <root>", typeText: "Unit" }
+// EXIST: { lookupString:"anyF", itemText:"anyF", tailText: "(s: String) for Any in <root>", typeText: "Unit" }
+// NOTHING_ELSE

idea/idea-completion/testData/smart/callableReference/NonEmptyQualifier2.kt

@@ -12,4 +12,5 @@ val Any.xTopLevelValOnAny: Int get()  = 1
 val Int.xTopLevelValOnInt: Int get()  = 1
 
 // EXIST: { lookupString:"xTopLevelIntVal", itemText:"xTopLevelIntVal", tailText: " for String in <root>", typeText: "Int" }
+// EXIST: { lookupString:"xTopLevelValOnAny", itemText:"xTopLevelValOnAny", tailText: " for Any in <root>", typeText: "Int" }
 // NOTHING_ELSE

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/JvmSmartCompletionTestGenerated.java

@@ -721,6 +721,12 @@ public class JvmSmartCompletionTestGenerated extends AbstractJvmSmartCompletionT
             doTest(fileName);
         }
 
+        @TestMetadata("ExpressionQualifier.kt")
+        public void testExpressionQualifier() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/smart/callableReference/ExpressionQualifier.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("NoQualifier1.kt")
         public void testNoQualifier1() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/smart/callableReference/NoQualifier1.kt");