Smart completion to use super type for override if no explicit type specified

idea/idea-completion/testData/smart/ImplicitlyTypedOverrideFunBody.kt

@@ -0,0 +1,13 @@
+abstract class Base {
+    abstract fun foo(): Int
+}
+
+class Derived : Base() {
+    override fun foo() = <caret>
+}
+
+fun getInt(): Int = 0
+fun getString(): String = ""
+
+// EXIST: getInt
+// ABSENT: getString

idea/idea-completion/testData/smart/ImplicitlyTypedOverrideValInitializer.kt

@@ -0,0 +1,13 @@
+abstract class Base {
+    abstract val foo: Int
+}
+
+class Derived : Base() {
+    override val foo = <caret>
+}
+
+fun getInt(): Int = 0
+fun getString(): String = ""
+
+// EXIST: getInt
+// ABSENT: getString

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

@@ -185,6 +185,18 @@ public class JvmSmartCompletionTestGenerated extends AbstractJvmSmartCompletionT
         doTest(fileName);
     }
 
+    @TestMetadata("ImplicitlyTypedOverrideFunBody.kt")
+    public void testImplicitlyTypedOverrideFunBody() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/smart/ImplicitlyTypedOverrideFunBody.kt");
+        doTest(fileName);
+    }
+
+    @TestMetadata("ImplicitlyTypedOverrideValInitializer.kt")
+    public void testImplicitlyTypedOverrideValInitializer() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/smart/ImplicitlyTypedOverrideValInitializer.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("ImplicitlyTypedValInitializer1.kt")
     public void testImplicitlyTypedValInitializer1() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/smart/ImplicitlyTypedValInitializer1.kt");

idea/idea-core/src/org/jetbrains/kotlin/idea/core/ExpectedInfos.kt

@@ -527,10 +527,11 @@ class ExpectedInfos(
         if (expressionWithType != property.initializer) return null
         val propertyDescriptor = bindingContext[BindingContext.DECLARATION_TO_DESCRIPTOR, property] as? VariableDescriptor ?: return null
         val expectedName = propertyDescriptor.name.asString()
-        val expectedInfo = if (property.typeReference != null)
+        val returnTypeToUse = returnTypeToUse(propertyDescriptor, hasExplicitReturnType = property.typeReference != null)
-            ExpectedInfo(propertyDescriptor.type, expectedName, null)
+        val expectedInfo = if (returnTypeToUse != null)
+            ExpectedInfo(returnTypeToUse, expectedName, null)
         else
-            ExpectedInfo(ByTypeFilter.All, expectedName, null) // no explicit type - only expected name known
+            ExpectedInfo(ByTypeFilter.All, expectedName, null) // no explicit type or type from base - only expected name known
         return listOf(expectedInfo)
     }
 
@@ -538,33 +539,38 @@ class ExpectedInfos(
         val declaration = expressionWithType.parent as? KtDeclarationWithBody ?: return null
         if (expressionWithType != declaration.bodyExpression || declaration.hasBlockBody()) return null
         val descriptor = bindingContext[BindingContext.DECLARATION_TO_DESCRIPTOR, declaration] as? FunctionDescriptor ?: return null
-        return functionReturnValueExpectedInfo(descriptor, expectType = declaration.hasDeclaredReturnType()).singletonOrEmptyList()
+        return functionReturnValueExpectedInfo(descriptor, hasExplicitReturnType = declaration.hasDeclaredReturnType()).singletonOrEmptyList()
     }
 
     private fun calculateForReturn(expressionWithType: KtExpression): Collection<ExpectedInfo>? {
         val returnExpression = expressionWithType.parent as? KtReturnExpression ?: return null
         val descriptor = returnExpression.getTargetFunctionDescriptor(bindingContext) ?: return null
-        return functionReturnValueExpectedInfo(descriptor, expectType = true).singletonOrEmptyList()
+        return functionReturnValueExpectedInfo(descriptor, hasExplicitReturnType = true).singletonOrEmptyList()
     }
 
-    private fun functionReturnValueExpectedInfo(descriptor: FunctionDescriptor, expectType: Boolean): ExpectedInfo? {
+    private fun functionReturnValueExpectedInfo(descriptor: FunctionDescriptor, hasExplicitReturnType: Boolean): ExpectedInfo? {
         return when (descriptor) {
             is SimpleFunctionDescriptor -> {
-                val expectedType = if (expectType) descriptor.returnType else null
+                ExpectedInfo.createForReturnValue(returnTypeToUse(descriptor, hasExplicitReturnType), descriptor)
-                ExpectedInfo.createForReturnValue(expectedType, descriptor)
             }
 
             is PropertyGetterDescriptor -> {
                 if (descriptor !is PropertyGetterDescriptor) return null
                 val property = descriptor.correspondingProperty
-                val expectedType = if (expectType) property.type else null
+                ExpectedInfo.createForReturnValue(returnTypeToUse(property, hasExplicitReturnType), property)
-                ExpectedInfo.createForReturnValue(expectedType, property)
             }
 
             else -> null
         }
     }
 
+    private fun returnTypeToUse(descriptor: CallableDescriptor, hasExplicitReturnType: Boolean): KotlinType? {
+        return if (hasExplicitReturnType)
+            descriptor.returnType
+        else
+            descriptor.overriddenDescriptors.singleOrNull()?.returnType
+    }
+
     private fun calculateForLoopRange(expressionWithType: KtExpression): Collection<ExpectedInfo>? {
         val forExpression = (expressionWithType.parent as? KtContainerNode)
                                     ?.parent as? KtForExpression ?: return null