KT-9835 Completion thinks receiver is nullable when it is not

#KT-9835 Fixed

compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaSyntheticPropertiesScope.kt

@@ -352,7 +352,7 @@ class JavaSyntheticPropertiesScope(storageManager: StorageManager, private val l
         }
 
         override fun substitute(originalSubstitutor: TypeSubstitutor): PropertyDescriptor? {
-            val descriptor = super.substitute(originalSubstitutor) as MyPropertyDescriptor
+            val descriptor = super.substitute(originalSubstitutor) as MyPropertyDescriptor? ?: return null
             if (descriptor == this) return descriptor
 
             val classTypeParameters = (getMethod.containingDeclaration as ClassDescriptor).typeConstructor.parameters
@@ -362,7 +362,10 @@ class JavaSyntheticPropertiesScope(storageManager: StorageManager, private val l
                 substitutionMap[classTypeParameter.typeConstructor] = typeProjection
 
             }
-            val classParametersSubstitutor = TypeSubstitutor.create(substitutionMap)
+            val classParametersSubstitutor = TypeConstructorSubstitution.createByConstructorsMap(
+                    substitutionMap,
+                    approximateCapturedTypes = true
+            ).buildSubstitutor()
 
             descriptor.getMethod = getMethod.substitute(classParametersSubstitutor) ?: return null
             descriptor.setMethod = setMethod?.substitute(classParametersSubstitutor)

idea/ide-common/src/org/jetbrains/kotlin/idea/util/FuzzyType.kt

@@ -27,6 +27,7 @@ import org.jetbrains.kotlin.resolve.calls.inference.constraintPosition.Constrain
 import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.types.checker.StrictEqualityTypeChecker
 import org.jetbrains.kotlin.types.typeUtil.*
+import org.jetbrains.kotlin.utils.addToStdlib.check
 import java.util.*
 
 fun CallableDescriptor.fuzzyReturnType() = returnType?.toFuzzyType(typeParameters)
@@ -170,13 +171,20 @@ class FuzzyType(
         if (otherSubstitutedType.isError) return TypeSubstitutor.EMPTY
         if (!substitutedType.checkInheritance(otherSubstitutedType)) return null
 
-        val substitution = constraintSystem.typeVariables.map { it.originalTypeParameter }.associateBy({ it.typeConstructor }) {
+        val substitutorToKeepCapturedTypes = object : DelegatedTypeSubstitution(substitutor.substitution) {
-            val type = it.defaultType
+            override fun approximateCapturedTypes() = false
-            val solution = substitutor.substitute(type, Variance.INVARIANT)
+        }.buildSubstitutor()
-            TypeProjectionImpl(if (solution != null && !ErrorUtils.containsUninferredParameter(solution)) solution else type)
-        }
 
-        return TypeSubstitutor.create(TypeConstructorSubstitution.createByConstructorsMap(substitution))
+        val substitutionMap: Map<TypeConstructor, TypeProjection> = constraintSystem.typeVariables
+                .map { it.originalTypeParameter }
+                .associateBy(
+                        keySelector = { it.typeConstructor },
+                        valueTransform = {
+                            val typeProjection = TypeProjectionImpl(Variance.INVARIANT, it.defaultType)
+                            val substitutedProjection = substitutorToKeepCapturedTypes.substitute(typeProjection)
+                            substitutedProjection?.check { !ErrorUtils.containsUninferredParameter(it.type) } ?: typeProjection
+                        })
+        return TypeConstructorSubstitution.createByConstructorsMap(substitutionMap, approximateCapturedTypes = true).buildSubstitutor()
     }
 }
 

idea/ide-common/src/org/jetbrains/kotlin/idea/util/extensionsUtils.kt

@@ -27,8 +27,8 @@ import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowInfo
 import org.jetbrains.kotlin.resolve.calls.smartcasts.SmartCastManager
 import org.jetbrains.kotlin.resolve.scopes.LexicalScope
 import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver
-import org.jetbrains.kotlin.resolve.scopes.receivers.ReceiverValue
 import org.jetbrains.kotlin.resolve.scopes.receivers.ImplicitReceiver
+import org.jetbrains.kotlin.resolve.scopes.receivers.ReceiverValue
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.typeUtil.TypeNullability
 import org.jetbrains.kotlin.types.typeUtil.makeNotNullable
@@ -95,7 +95,9 @@ fun <TCallable : CallableDescriptor> TCallable.substituteExtensionIfCallable(
         return if (substitutors.any()) listOf(this) else listOf()
     }
     else {
-        return substitutors.map { @Suppress("UNCHECKED_CAST") (substitute(it) as TCallable) }.toList()
+        return substitutors
+                .mapNotNull { @Suppress("UNCHECKED_CAST") (substitute(it) as TCallable?) }
+                .toList()
     }
 }
 

idea/idea-completion/testData/basic/common/boldOrGrayed/KT9835.kt

@@ -0,0 +1,15 @@
+interface R<T>
+
+val <T> R<T>.prop: Int get() = TODO()
+fun <T> R<T>.extFun(): Int = TODO()
+
+interface I
+
+fun foo(r: R<out I>) {
+    r.<caret>
+}
+
+// EXIST: { itemText: "prop", typeText: "Int", attributes: "bold" }
+// EXIST: { itemText: "extFun", typeText: "Int", attributes: "bold" }
+
+

idea/idea-completion/testData/basic/java/syntheticExtensions/InGenericClass.kt

@@ -2,9 +2,14 @@ fun foo(klass: Class<*>) {
     klass.<caret>
 }
 
+fun <T> Class<T>.extFun(): Class<in T> = TODO()
+
 // EXIST: simpleName
 // ABSENT: getSimpleName
 // EXIST: enclosingClass
 // ABSENT: getEnclosingClass
 // EXIST: annotations
 // ABSENT: getAnnotations
+// EXIST: superclass
+// ABSENT: getSuperclass
+// EXIST: extFun

idea/idea-completion/testData/basic/multifile/KT9835/KT9835.java

@@ -0,0 +1,4 @@
+public interface R<D extends I> {
+    int getFoo();
+    int f();
+}

idea/idea-completion/testData/basic/multifile/KT9835/KT9835.kt

@@ -0,0 +1,8 @@
+interface I
+
+fun foo(r: R<out I>) {
+    r.<caret>
+}
+
+// EXIST: { itemText: "foo", tailText: " (from getFoo())", typeText: "Int", attributes: "bold" }
+// EXIST: { itemText: "f", tailText: "()", typeText: "Int", attributes: "bold" }

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

@@ -1197,6 +1197,12 @@ public class JSBasicCompletionTestGenerated extends AbstractJSBasicCompletionTes
                 doTest(fileName);
             }
 
+            @TestMetadata("KT9835.kt")
+            public void testKT9835() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/boldOrGrayed/KT9835.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("NonPredictableSmartCast.kt")
             public void testNonPredictableSmartCast() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/boldOrGrayed/NonPredictableSmartCast.kt");

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

@@ -1197,6 +1197,12 @@ public class JvmBasicCompletionTestGenerated extends AbstractJvmBasicCompletionT
                 doTest(fileName);
             }
 
+            @TestMetadata("KT9835.kt")
+            public void testKT9835() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/boldOrGrayed/KT9835.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("NonPredictableSmartCast.kt")
             public void testNonPredictableSmartCast() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/boldOrGrayed/NonPredictableSmartCast.kt");

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

@@ -209,6 +209,12 @@ public class MultiFileJvmBasicCompletionTestGenerated extends AbstractMultiFileJ
         doTest(fileName);
     }
 
+    @TestMetadata("KT9835")
+    public void testKT9835() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/multifile/KT9835/");
+        doTest(fileName);
+    }
+
     @TestMetadata("MoreSpecificExtensionGeneric")
     public void testMoreSpecificExtensionGeneric() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/multifile/MoreSpecificExtensionGeneric/");