unqualified super: should be able to invoke methods of Any without extra hassle

when Any is an implicit immediate superclass

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/BasicExpressionTypingVisitor.java

@@ -392,9 +392,10 @@ public class BasicExpressionTypingVisitor extends ExpressionTypingVisitor {
             }
         }
         else {
-            if (supertypes.size() > 1) {
+            if (UnqualifiedSuperPackage.isPossiblyAmbiguousUnqualifiedSuper(expression, supertypes)) {
                 Collection<JetType> supertypesResolvedFromContext =
-                        UnqualifiedSuperPackage.resolveUnqualifiedSuperFromExpressionContext(expression, supertypes);
+                        UnqualifiedSuperPackage.resolveUnqualifiedSuperFromExpressionContext(
+                                expression, supertypes, components.builtIns.getAnyType());
                 if (supertypesResolvedFromContext.size() == 1) {
                     JetType singleResolvedType = supertypesResolvedFromContext.iterator().next();
                     result = substitutor.substitute(singleResolvedType, Variance.INVARIANT);

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/unqualifiedSuper/unqualifiedSuper.kt

@@ -17,33 +17,47 @@
 package org.jetbrains.kotlin.types.expressions.unqualifiedSuper
 
 import com.intellij.util.SmartList
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
+import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.MemberDescriptor
 import org.jetbrains.kotlin.descriptors.Modality
-import org.jetbrains.kotlin.descriptors.VariableDescriptor
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.JetCallExpression
 import org.jetbrains.kotlin.psi.JetDotQualifiedExpression
 import org.jetbrains.kotlin.psi.JetSimpleNameExpression
 import org.jetbrains.kotlin.psi.JetSuperExpression
 import org.jetbrains.kotlin.types.JetType
+import org.jetbrains.kotlin.types.TypeUtils
 import org.jetbrains.kotlin.utils.addToStdlib.singletonList
-import java.util.*
 
-public fun resolveUnqualifiedSuperFromExpressionContext(superExpression: JetSuperExpression, supertypes: Collection<JetType>): Collection<JetType> {
-    val parentElement = superExpression.getParent()
+
+public fun resolveUnqualifiedSuperFromExpressionContext(
+        superExpression: JetSuperExpression,
+        supertypes: Collection<JetType>,
+        anyType: JetType
+): Collection<JetType> {
+    val parentElement = superExpression.parent
 
     if (parentElement is JetDotQualifiedExpression) {
-        val selectorExpression = parentElement.getSelectorExpression()
+        val selectorExpression = parentElement.selectorExpression
         when (selectorExpression) {
             is JetCallExpression -> {
                 // super.foo(...): foo can be a function or a property of a callable type
-                val calleeExpression = selectorExpression.getCalleeExpression()
+                val calleeExpression = selectorExpression.calleeExpression
                 if (calleeExpression is JetSimpleNameExpression) {
-                    return resolveSupertypesByCalleeName(supertypes, calleeExpression.getReferencedNameAsName())
+                    val calleeName = calleeExpression.getReferencedNameAsName()
+                    if (isCallingMethodOfAny(selectorExpression, calleeName)) {
+                        return resolveSupertypesForMethodOfAny(supertypes, calleeName, anyType)
+                    }
+                    else {
+                        return resolveSupertypesByCalleeName(supertypes, calleeName)
+                    }
                 }
             }
             is JetSimpleNameExpression -> {
                 // super.x: x can be a property only
+                // NB there are no properties in kotlin.Any
                 return resolveSupertypesByPropertyName(supertypes, selectorExpression.getReferencedNameAsName())
             }
         }
@@ -52,37 +66,92 @@ public fun resolveUnqualifiedSuperFromExpressionContext(superExpression: JetSupe
     return emptyList()
 }
 
-private fun resolveSupertypesByCalleeName(supertypes: Collection<JetType>, calleeName: Name): Collection<JetType> =
-        resolveSupertypesByMembers(supertypes) { getFunctionMembers(it, calleeName) + getPropertyMembers(it, calleeName) }
+private val ARITY_OF_METHODS_OF_ANY = hashMapOf("hashCode" to 0, "equals" to 1, "toString" to 0)
 
-private fun resolveSupertypesByPropertyName(supertypes: Collection<JetType>, propertyName: Name): Collection<JetType> =
-        resolveSupertypesByMembers(supertypes) { getPropertyMembers(it, propertyName) }
+private fun isCallingMethodOfAny(callExpression: JetCallExpression, calleeName: Name): Boolean =
+        ARITY_OF_METHODS_OF_ANY.getOrElse(calleeName.asString(), { -1 }) == callExpression.valueArguments.size()
 
-private inline fun resolveSupertypesByMembers(
-        supertypes: Collection<JetType>,
-        getMembers: (JetType) -> Collection<MemberDescriptor>
-): Collection<JetType> {
-    val withConcreteMembers = SmartList<JetType>()
-    val withAnyMembers = SmartList<JetType>()
+public fun isPossiblyAmbiguousUnqualifiedSuper(superExpression: JetSuperExpression, supertypes: Collection<JetType>): Boolean =
+        supertypes.size() > 1 ||
+        (supertypes.size() == 1 && supertypes.single().isInterface() && isCallingMethodOfAnyWithSuper(superExpression))
 
-    for (supertype in supertypes) {
-        val members = getMembers(supertype)
-        if (members.isNotEmpty()) {
-            withAnyMembers.add(supertype)
-            if (members any ::isConcreteMember) {
-                withConcreteMembers.add(supertype)
+private fun isCallingMethodOfAnyWithSuper(superExpression: JetSuperExpression): Boolean {
+    val parent = superExpression.parent
+    if (parent is JetDotQualifiedExpression) {
+        val selectorExpression = parent.selectorExpression
+        if (selectorExpression is JetCallExpression) {
+            val calleeExpression = selectorExpression.calleeExpression
+            if (calleeExpression is JetSimpleNameExpression) {
+                val calleeName = calleeExpression.getReferencedNameAsName()
+                return isCallingMethodOfAny(selectorExpression, calleeName)
             }
         }
     }
 
-    return if (withConcreteMembers.isNotEmpty()) withConcreteMembers else withAnyMembers
+    return false
+}
+
+private fun JetType.isInterface(): Boolean =
+        TypeUtils.getClassDescriptor(this)?.kind == ClassKind.INTERFACE
+
+private fun resolveSupertypesForMethodOfAny(supertypes: Collection<JetType>, calleeName: Name, anyType: JetType): Collection<JetType> {
+    val typesWithConcreteOverride = resolveSupertypesByMembers(supertypes, false) { getFunctionMembers(it, calleeName) }
+    return if (typesWithConcreteOverride.isNotEmpty())
+        typesWithConcreteOverride
+    else
+        anyType.singletonList()
+}
+
+private fun resolveSupertypesByCalleeName(supertypes: Collection<JetType>, calleeName: Name): Collection<JetType> =
+        resolveSupertypesByMembers(supertypes, true) { getFunctionMembers(it, calleeName) + getPropertyMembers(it, calleeName) }
+
+private fun resolveSupertypesByPropertyName(supertypes: Collection<JetType>, propertyName: Name): Collection<JetType> =
+        resolveSupertypesByMembers(supertypes, true) { getPropertyMembers(it, propertyName) }
+
+private inline fun resolveSupertypesByMembers(
+        supertypes: Collection<JetType>,
+        allowArbitraryMembers: Boolean,
+        getMembers: (JetType) -> Collection<MemberDescriptor>
+): Collection<JetType> {
+    val typesWithConcreteMembers = SmartList<JetType>()
+    val typesWithArbitraryMembers = SmartList<JetType>()
+
+    for (supertype in supertypes) {
+        val members = getMembers(supertype)
+        if (members.isNotEmpty()) {
+            typesWithArbitraryMembers.add(supertype)
+            if (members.any { isConcreteMember(supertype, it) }) {
+                typesWithConcreteMembers.add(supertype)
+            }
+        }
+    }
+
+    return if (typesWithConcreteMembers.isNotEmpty()) typesWithConcreteMembers
+        else if (allowArbitraryMembers) typesWithArbitraryMembers
+        else emptyList<JetType>()
 }
 
 private fun getFunctionMembers(type: JetType, name: Name): Collection<MemberDescriptor> =
-        type.getMemberScope().getFunctions(name)
+        type.memberScope.getFunctions(name)
 
 private fun getPropertyMembers(type: JetType, name: Name): Collection<MemberDescriptor> =
-        type.getMemberScope().getProperties(name).filterIsInstanceTo(SmartList<MemberDescriptor>())
+        type.memberScope.getProperties(name).filterIsInstanceTo(SmartList<MemberDescriptor>())
 
-private fun isConcreteMember(memberDescriptor: MemberDescriptor): Boolean =
-        memberDescriptor.getModality() != Modality.ABSTRACT
+private fun isConcreteMember(supertype: JetType, memberDescriptor: MemberDescriptor): Boolean {
+    // "Concrete member" is a function or a property that is not abstract,
+    // and is not an implicit fake override for a method of Any on an interface.
+
+    if (memberDescriptor.modality == Modality.ABSTRACT)
+        return false
+
+    val classDescriptorForSupertype = TypeUtils.getClassDescriptor(supertype)
+    val memberKind = (memberDescriptor as CallableMemberDescriptor).kind
+    if (classDescriptorForSupertype?.kind == ClassKind.INTERFACE && memberKind == CallableMemberDescriptor.Kind.FAKE_OVERRIDE) {
+        // We have a fake override on interface. It should have a dispatch receiver, which should not be Any.
+        val dispatchReceiverType = memberDescriptor.dispatchReceiverParameter?.type ?: return false
+        val dispatchReceiverClass = TypeUtils.getClassDescriptor(dispatchReceiverType) ?: return false
+        return !KotlinBuiltIns.isAny(dispatchReceiverClass)
+    }
+
+    return true
+}

compiler/testData/codegen/box/super/unqualifiedSuperWithMethodsOfAny.kt

@@ -0,0 +1,34 @@
+interface ISomething
+
+open class ClassWithToString {
+    override fun toString(): String = "C"
+}
+
+interface IWithToString {
+    override fun toString(): String
+}
+
+interface IWithDefaultToString {
+    override fun toString(): String = "I"
+}
+
+class C1 : ClassWithToString(), ISomething {
+    override fun toString(): String = super.toString()
+}
+
+class C2 : ClassWithToString(), IWithToString, ISomething  {
+    override fun toString(): String = super.toString()
+}
+
+class C3 : IWithDefaultToString, ISomething  {
+    override fun toString(): String = super.toString()
+}
+
+fun box(): String {
+    return when {
+        C1().toString() != "C" -> "Failed #1"
+        C2().toString() != "C" -> "Failed #2"
+        C3().toString() != "I" -> "Failed #3"
+        else -> "OK"
+    }
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withAmbiguousMethodOfAny.kt

@@ -0,0 +1,12 @@
+interface IA {
+    override fun toString(): String = "IA"
+}
+
+interface IB {
+    override fun toString(): String = "IB"
+}
+
+class C : IA, IB {
+    override fun toString(): String =
+            <!AMBIGUOUS_SUPER!>super<!>.<!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>toString<!>()
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withAmbiguousMethodOfAny.txt

@@ -0,0 +1,20 @@
+package
+
+internal final class C : IA, IB {
+    public constructor C()
+    public open override /*2*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*2*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*2*/ fun toString(): kotlin.String
+}
+
+internal interface IA {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun toString(): kotlin.String
+}
+
+internal interface IB {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodOfAnyImplementedInSuperInterface.kt

@@ -0,0 +1,12 @@
+interface A {
+    override fun toString(): String {
+        return "OK"
+    }
+}
+
+interface B : A
+
+class C : B {
+    override fun toString(): String =
+            super.toString()
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodOfAnyImplementedInSuperInterface.txt

@@ -0,0 +1,20 @@
+package
+
+internal interface A {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun toString(): kotlin.String
+}
+
+internal interface B : A {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal final class C : B {
+    public constructor C()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodOfAnyOverridenInInterface.kt

@@ -0,0 +1,16 @@
+interface IWithToString {
+    override fun toString(): String
+}
+
+class A : IWithToString {
+    // Should be Any#toString(), even though IWithToString defines an abstract toString.
+    override fun toString(): String = super.toString()
+}
+
+interface IWithImplementedToString {
+    override fun toString(): String = "Heh"
+}
+
+class B : IWithImplementedToString {
+    override fun toString(): String = super.toString()
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodOfAnyOverridenInInterface.txt

@@ -0,0 +1,27 @@
+package
+
+internal final class A : IWithToString {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun toString(): kotlin.String
+}
+
+internal final class B : IWithImplementedToString {
+    public constructor B()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun toString(): kotlin.String
+}
+
+internal interface IWithImplementedToString {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun toString(): kotlin.String
+}
+
+internal interface IWithToString {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public abstract override /*1*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodsOfAny.kt

@@ -0,0 +1,10 @@
+interface IFoo
+
+interface IBar
+
+class A : IFoo, IBar {
+    // Unqualified 'super' should be resolved to 'Any'.
+    override fun equals(other: Any?): Boolean = super.equals(other)
+    override fun hashCode(): Int = super.hashCode()
+    override fun toString(): String = super.toString()
+}

compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodsOfAny.txt

@@ -0,0 +1,20 @@
+package
+
+internal final class A : IFoo, IBar {
+    public constructor A()
+    public open override /*2*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*2*/ fun hashCode(): kotlin.Int
+    public open override /*2*/ fun toString(): kotlin.String
+}
+
+internal interface IBar {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+internal interface IFoo {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/tests/org/jetbrains/kotlin/checkers/JetDiagnosticsTestGenerated.java

@@ -14584,6 +14584,30 @@ public class JetDiagnosticsTestGenerated extends AbstractJetDiagnosticsTest {
                     String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/unqualifiedSuperWithUnresolvedBase.kt");
                     doTest(fileName);
                 }
+
+                @TestMetadata("withAmbiguousMethodOfAny.kt")
+                public void testWithAmbiguousMethodOfAny() throws Exception {
+                    String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withAmbiguousMethodOfAny.kt");
+                    doTest(fileName);
+                }
+
+                @TestMetadata("withMethodOfAnyImplementedInSuperInterface.kt")
+                public void testWithMethodOfAnyImplementedInSuperInterface() throws Exception {
+                    String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodOfAnyImplementedInSuperInterface.kt");
+                    doTest(fileName);
+                }
+
+                @TestMetadata("withMethodOfAnyOverridenInInterface.kt")
+                public void testWithMethodOfAnyOverridenInInterface() throws Exception {
+                    String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodOfAnyOverridenInInterface.kt");
+                    doTest(fileName);
+                }
+
+                @TestMetadata("withMethodsOfAny.kt")
+                public void testWithMethodsOfAny() throws Exception {
+                    String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/thisAndSuper/unqualifiedSuper/withMethodsOfAny.kt");
+                    doTest(fileName);
+                }
             }
         }
 

compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxCodegenTestGenerated.java

@@ -7185,6 +7185,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/box/super/unqualifiedSuperWithLocalClass.kt");
             doTest(fileName);
         }
+
+        @TestMetadata("unqualifiedSuperWithMethodsOfAny.kt")
+        public void testUnqualifiedSuperWithMethodsOfAny() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/box/super/unqualifiedSuperWithMethodsOfAny.kt");
+            doTest(fileName);
+        }
     }
 
     @TestMetadata("compiler/testData/codegen/box/superConstructorCall")