FIR: Implement FE 1.0 semantics for super unqualified calls

See original logic at org.jetbrains.kotlin.types.expressions.unqualifiedSuper.UnqualifiedSuperKt#resolveUnqualifiedSuperFromExpressionContext

^KT-39070 Fixed
^KT-39599 Related

compiler/fir/analysis-tests/testData/resolve/callResolution/superAny.kt

@@ -0,0 +1,21 @@
+interface A
+
+open class B {
+    override fun equals(other: Any?): Boolean {
+        return super.equals(other)
+    }
+
+    override fun hashCode(): Int {
+        return super.hashCode()
+    }
+}
+
+class C : A, B() {
+    override fun equals(other: Any?): Boolean {
+        return super.equals(other)
+    }
+
+    override fun hashCode(): Int {
+        return super.hashCode()
+    }
+}

compiler/fir/analysis-tests/testData/resolve/callResolution/superAny.txt

@@ -0,0 +1,31 @@
+FILE: superAny.kt
+    public abstract interface A : R|kotlin/Any| {
+    }
+    public open class B : R|kotlin/Any| {
+        public constructor(): R|B| {
+            super<R|kotlin/Any|>()
+        }
+
+        public open override fun equals(other: R|kotlin/Any?|): R|kotlin/Boolean| {
+            ^equals this@R|/B|.super<R|kotlin/Any|>.R|kotlin/Any.equals|(R|<local>/other|)
+        }
+
+        public open override fun hashCode(): R|kotlin/Int| {
+            ^hashCode this@R|/B|.super<R|kotlin/Any|>.R|kotlin/Any.hashCode|()
+        }
+
+    }
+    public final class C : R|A|, R|B| {
+        public constructor(): R|C| {
+            super<R|B|>()
+        }
+
+        public final override fun equals(other: R|kotlin/Any?|): R|kotlin/Boolean| {
+            ^equals this@R|/C|.super<R|B|>.R|/B.equals|(R|<local>/other|)
+        }
+
+        public final override fun hashCode(): R|kotlin/Int| {
+            ^hashCode this@R|/C|.super<R|B|>.R|/B.hashCode|()
+        }
+
+    }

compiler/fir/analysis-tests/testData/resolve/incorrectSuperCall.kt

@@ -15,7 +15,7 @@ class C : A, B() {
     override fun foo() {
         super.foo()
 
-        super.<!AMBIGUITY!>bar<!>() // should be ambiguity (NB: really we should have overridden bar in C)
+        super.<!UNRESOLVED_REFERENCE!>bar<!>() // should be ambiguity (NB: really we should have overridden bar in C)
 
         super.baz() // Ok
         baz()       // Ok

compiler/fir/analysis-tests/testData/resolve/incorrectSuperCall.txt

@@ -27,9 +27,9 @@ FILE: incorrectSuperCall.kt
         }
 
         public final override fun foo(): R|kotlin/Unit| {
-            this@R|/C|.super<R|A|R|B|>.R|/B.foo|()
-            this@R|/C|.super<R|A|R|B|>.<Ambiguity: bar, [/A.bar, /B.bar]>#()
-            this@R|/C|.super<R|A|R|B|>.R|/B.baz|()
+            this@R|/C|.super<R|B|>.R|/B.foo|()
+            this@R|/C|.super<<ERROR TYPE REF: Ambiguous supertype>>.<Unresolved name: bar>#()
+            this@R|/C|.super<R|B|>.R|/B.baz|()
             this@R|/C|.R|/A.baz|()
         }
 

compiler/fir/analysis-tests/tests/org/jetbrains/kotlin/fir/FirDiagnosticsTestGenerated.java

@@ -654,6 +654,11 @@ public class FirDiagnosticsTestGenerated extends AbstractFirDiagnosticsTest {
             runTest("compiler/fir/analysis-tests/testData/resolve/callResolution/safeCallOnTypeAlias.kt");
         }
 
+        @TestMetadata("superAny.kt")
+        public void testSuperAny() throws Exception {
+            runTest("compiler/fir/analysis-tests/testData/resolve/callResolution/superAny.kt");
+        }
+
         @TestMetadata("syntheticPropertiesWrongImplicitReceiver.kt")
         public void testSyntheticPropertiesWrongImplicitReceiver() throws Exception {
             runTest("compiler/fir/analysis-tests/testData/resolve/callResolution/syntheticPropertiesWrongImplicitReceiver.kt");

compiler/fir/analysis-tests/tests/org/jetbrains/kotlin/fir/FirDiagnosticsWithLightTreeTestGenerated.java

@@ -654,6 +654,11 @@ public class FirDiagnosticsWithLightTreeTestGenerated extends AbstractFirDiagnos
             runTest("compiler/fir/analysis-tests/testData/resolve/callResolution/safeCallOnTypeAlias.kt");
         }
 
+        @TestMetadata("superAny.kt")
+        public void testSuperAny() throws Exception {
+            runTest("compiler/fir/analysis-tests/testData/resolve/callResolution/superAny.kt");
+        }
+
         @TestMetadata("syntheticPropertiesWrongImplicitReceiver.kt")
         public void testSyntheticPropertiesWrongImplicitReceiver() throws Exception {
             runTest("compiler/fir/analysis-tests/testData/resolve/callResolution/syntheticPropertiesWrongImplicitReceiver.kt");

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirNotASupertypeChecker.kt

@@ -20,7 +20,7 @@ import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
 object FirNotASupertypeChecker : FirQualifiedAccessChecker() {
     override fun check(functionCall: FirQualifiedAccessExpression, context: CheckerContext, reporter: DiagnosticReporter) {
-        val superReference = functionCall.calleeReference.safeAs<FirSuperReference>()
+        val superReference = functionCall.calleeReference.safeAs<FirSuperReference>()?.takeIf { it.hadExplicitTypeInSource() }
 
         val targetClass = superReference
             ?.superTypeRef
@@ -57,4 +57,4 @@ object FirNotASupertypeChecker : FirQualifiedAccessChecker() {
             report(FirErrors.NOT_A_SUPERTYPE.on(it))
         }
     }
-}
+}

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirQualifiedSupertypeExtendedByOtherSupertypeChecker.kt

@@ -23,6 +23,7 @@ object FirQualifiedSupertypeExtendedByOtherSupertypeChecker : FirQualifiedAccess
     override fun check(functionCall: FirQualifiedAccessExpression, context: CheckerContext, reporter: DiagnosticReporter) {
         // require to be called over a super reference
         val superReference = functionCall.calleeReference.safeAs<FirSuperReference>()
+            ?.takeIf { it.hadExplicitTypeInSource() }
             ?: return
 
         val explicitType = superReference.superTypeRef.safeAs<FirResolvedTypeRef>()
@@ -62,4 +63,4 @@ object FirQualifiedSupertypeExtendedByOtherSupertypeChecker : FirQualifiedAccess
             report(FirErrors.QUALIFIED_SUPERTYPE_EXTENDED_BY_OTHER_SUPERTYPE.on(it))
         }
     }
-}
+}

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/FirSuperNotAvailableChecker.kt

@@ -5,23 +5,26 @@
 
 package org.jetbrains.kotlin.fir.analysis.checkers.expression
 
-import org.jetbrains.kotlin.KtNodeTypes.*
+import org.jetbrains.kotlin.KtNodeTypes.CLASS
+import org.jetbrains.kotlin.KtNodeTypes.OBJECT_LITERAL
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
 import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors
 import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccessExpression
+import org.jetbrains.kotlin.fir.references.FirSuperReference
+import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
 object FirSuperNotAvailableChecker : FirQualifiedAccessChecker() {
     override fun check(functionCall: FirQualifiedAccessExpression, context: CheckerContext, reporter: DiagnosticReporter) {
-        if (functionCall.source?.elementType == SUPER_EXPRESSION) {
-            val isInsideClass = context.containingDeclarations.any {
-                it.source?.elementType == CLASS || it.source?.elementType == OBJECT_LITERAL
-            }
+        if (functionCall.calleeReference.safeAs<FirSuperReference>()?.hadExplicitTypeInSource() != true) return
 
-            if (!isInsideClass) {
-                reporter.report(functionCall.source)
-            }
+        val isInsideClass = context.containingDeclarations.any {
+            it.source?.elementType == CLASS || it.source?.elementType == OBJECT_LITERAL
+        }
+
+        if (!isInsideClass) {
+            reporter.report(functionCall.source)
         }
     }
 
@@ -30,4 +33,4 @@ object FirSuperNotAvailableChecker : FirQualifiedAccessChecker() {
             report(FirErrors.SUPER_NOT_AVAILABLE.on(it))
         }
     }
-}
+}

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/expression/SuperCallCheckers.kt

@@ -0,0 +1,11 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.analysis.checkers.expression
+
+import org.jetbrains.kotlin.fir.FirFakeSourceElementKind
+import org.jetbrains.kotlin.fir.references.FirSuperReference
+
+fun FirSuperReference.hadExplicitTypeInSource(): Boolean = superTypeRef.source?.kind != FirFakeSourceElementKind.SuperCallImplicitType

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/FirCallResolver.kt

@@ -117,7 +117,7 @@ class FirCallResolver(
             explicitReceiver.calleeReference as? FirSuperReference
                 ?: return transformExplicitReceiver(transformer, ResolutionMode.ContextIndependent) as Q
 
-        transformer.transformSuperReceiver(callee, explicitReceiver)
+        transformer.transformSuperReceiver(callee, explicitReceiver, this)
 
         return this
     }

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/calls/SuperCalls.kt

@@ -0,0 +1,147 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.resolve.calls
+
+import com.intellij.util.SmartList
+import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.fir.declarations.FirCallableMemberDeclaration
+import org.jetbrains.kotlin.fir.declarations.FirProperty
+import org.jetbrains.kotlin.fir.declarations.FirSimpleFunction
+import org.jetbrains.kotlin.fir.declarations.modality
+import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
+import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccess
+import org.jetbrains.kotlin.fir.references.FirNamedReference
+import org.jetbrains.kotlin.fir.resolve.BodyResolveComponents
+import org.jetbrains.kotlin.fir.resolve.scope
+import org.jetbrains.kotlin.fir.resolve.toSymbol
+import org.jetbrains.kotlin.fir.symbols.StandardClassIds
+import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
+import org.jetbrains.kotlin.fir.symbols.impl.unwrapSubstitutionOverrides
+import org.jetbrains.kotlin.fir.typeContext
+import org.jetbrains.kotlin.fir.types.ConeClassLikeType
+import org.jetbrains.kotlin.fir.types.ConeKotlinType
+import org.jetbrains.kotlin.fir.types.FirResolvedTypeRef
+import org.jetbrains.kotlin.fir.types.FirTypeRef
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.types.AbstractTypeChecker
+import org.jetbrains.kotlin.utils.addIfNotNull
+
+fun BodyResolveComponents.findTypesForSuperCandidates(
+    superTypeRefs: List<FirTypeRef>,
+    containingCall: FirQualifiedAccess,
+): Collection<ConeKotlinType> {
+    val supertypes = superTypeRefs.map { (it as FirResolvedTypeRef).type }
+    if (supertypes.size <= 1) return supertypes
+
+    return when (containingCall) {
+        is FirFunctionCall -> {
+            val calleeName = containingCall.calleeReference.name
+            if (isCallingMethodOfAny(containingCall)) {
+                resolveSupertypesForMethodOfAny(supertypes, calleeName)
+            } else {
+                resolveSupertypesByCalleeName(supertypes, calleeName)
+            }
+        }
+        else -> {
+            resolveSupertypesByPropertyName(
+                supertypes,
+                (containingCall.calleeReference as? FirNamedReference)?.name ?: return emptyList()
+            )
+        }
+    }
+}
+
+private val ARITY_OF_METHODS_OF_ANY = hashMapOf("hashCode" to 0, "equals" to 1, "toString" to 0)
+
+private fun isCallingMethodOfAny(callExpression: FirFunctionCall): Boolean =
+    ARITY_OF_METHODS_OF_ANY.getOrElse(callExpression.calleeReference.name.asString(), { -1 }) == callExpression.argumentList.arguments.size
+
+private fun BodyResolveComponents.resolveSupertypesForMethodOfAny(
+    supertypes: Collection<ConeKotlinType>,
+    calleeName: Name
+): Collection<ConeKotlinType> {
+    val typesWithConcreteOverride = resolveSupertypesByMembers(supertypes, false) {
+        getFunctionMembers(it, calleeName)
+    }
+    return if (typesWithConcreteOverride.isNotEmpty())
+        typesWithConcreteOverride
+    else
+        listOf(session.builtinTypes.anyType.type)
+}
+
+private fun BodyResolveComponents.resolveSupertypesByCalleeName(supertypes: Collection<ConeKotlinType>, calleeName: Name): Collection<ConeKotlinType> =
+    resolveSupertypesByMembers(supertypes, true) {
+        getFunctionMembers(it, calleeName) +
+                getPropertyMembers(it, calleeName)
+    }
+
+private fun BodyResolveComponents.resolveSupertypesByPropertyName(supertypes: Collection<ConeKotlinType>, propertyName: Name): Collection<ConeKotlinType> =
+    resolveSupertypesByMembers(supertypes, true) {
+        getPropertyMembers(it, propertyName)
+    }
+
+private inline fun BodyResolveComponents.resolveSupertypesByMembers(
+    supertypes: Collection<ConeKotlinType>,
+    allowNonConcreteMembers: Boolean,
+    getMembers: (ConeKotlinType) -> Collection<FirCallableMemberDeclaration<*>>
+): Collection<ConeKotlinType> {
+    val typesWithConcreteMembers = SmartList<ConeKotlinType>()
+    val typesWithNonConcreteMembers = SmartList<ConeKotlinType>()
+
+    for (supertype in supertypes) {
+        val members = getMembers(supertype)
+        if (members.isNotEmpty()) {
+            if (members.any { isConcreteMember(supertype, it) })
+                typesWithConcreteMembers.add(supertype)
+            else
+                typesWithNonConcreteMembers.add(supertype)
+        }
+    }
+
+    typesWithConcreteMembers.removeAll { typeWithConcreteMember ->
+        typesWithNonConcreteMembers.any { typeWithNonConcreteMember ->
+            AbstractTypeChecker.isSubtypeOf(session.typeContext, typeWithNonConcreteMember, typeWithConcreteMember)
+        }
+    }
+
+    return when {
+        typesWithConcreteMembers.isNotEmpty() ->
+            typesWithConcreteMembers
+        allowNonConcreteMembers ->
+            typesWithNonConcreteMembers
+        else ->
+            emptyList()
+    }
+}
+
+@OptIn(ExperimentalStdlibApi::class)
+private fun BodyResolveComponents.getFunctionMembers(type: ConeKotlinType, name: Name): Collection<FirCallableMemberDeclaration<*>> = buildList {
+    type.scope(session, scopeSession)?.processFunctionsByName(name) {
+        addIfNotNull(it.fir as? FirSimpleFunction)
+    }
+}
+
+@OptIn(ExperimentalStdlibApi::class)
+private fun BodyResolveComponents.getPropertyMembers(type: ConeKotlinType, name: Name): Collection<FirCallableMemberDeclaration<*>> = buildList {
+    type.scope(session, scopeSession)?.processPropertiesByName(name) {
+        addIfNotNull(it.fir as? FirProperty)
+    }
+}
+
+
+private fun BodyResolveComponents.isConcreteMember(supertype: ConeKotlinType, member: FirCallableMemberDeclaration<*>): 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 (member.modality == Modality.ABSTRACT)
+        return false
+
+    val classSymbol =
+        (supertype as? ConeClassLikeType)?.lookupTag?.toSymbol(session) as? FirRegularClassSymbol ?: return true
+    if (classSymbol.fir.classKind != ClassKind.INTERFACE) return true
+    return member.symbol.unwrapSubstitutionOverrides().callableId.classId != StandardClassIds.Any
+}

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/body/resolve/FirExpressionsResolveTransformer.kt

@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.diagnostics.DiagnosticKind
 import org.jetbrains.kotlin.fir.expressions.*
 import org.jetbrains.kotlin.fir.expressions.builder.buildErrorExpression
 import org.jetbrains.kotlin.fir.expressions.builder.buildFunctionCall
-import org.jetbrains.kotlin.fir.expressions.builder.buildVarargArgumentsExpression
 import org.jetbrains.kotlin.fir.expressions.builder.buildVariableAssignment
 import org.jetbrains.kotlin.fir.references.*
 import org.jetbrains.kotlin.fir.references.builder.buildErrorNamedReference
@@ -39,7 +38,6 @@ import org.jetbrains.kotlin.fir.visitors.*
 import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.Variance
-import kotlin.math.min
 
 open class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransformer) : FirPartialBodyResolveTransformer(transformer) {
     private inline val builtinTypes: BuiltinTypes get() = session.builtinTypes
@@ -84,7 +82,7 @@ open class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransform
                 qualifiedAccessExpression
             }
             is FirSuperReference -> {
-                transformSuperReceiver(callee, qualifiedAccessExpression)
+                transformSuperReceiver(callee, qualifiedAccessExpression, null)
             }
             is FirDelegateFieldReference -> {
                 val delegateFieldSymbol = callee.resolvedSymbol
@@ -126,7 +124,8 @@ open class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransform
 
     fun transformSuperReceiver(
         superReference: FirSuperReference,
-        superReferenceContainer: FirQualifiedAccessExpression
+        superReferenceContainer: FirQualifiedAccessExpression,
+        containingCall: FirQualifiedAccess?
     ): FirQualifiedAccessExpression {
         val labelName = superReference.labelName
         val implicitReceiver =
@@ -146,21 +145,26 @@ open class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransform
             else -> {
                 val superTypeRefs = implicitReceiver?.boundSymbol?.phasedFir?.superTypeRefs
                 val resultType = when {
-                    superTypeRefs?.isNotEmpty() != true -> {
+                    superTypeRefs?.isNotEmpty() != true || containingCall == null -> {
                         buildErrorTypeRef {
                             source = superReferenceContainer.source
                             // NB: NOT_A_SUPERTYPE is reported by a separate checker
                             diagnostic = ConeStubDiagnostic(ConeSimpleDiagnostic("No super type", DiagnosticKind.Other))
                         }
                     }
-                    superTypeRefs.size == 1 -> {
-                        superTypeRefs.single()
-                    }
                     else -> {
-                        buildComposedSuperTypeRef {
-                            source = superReferenceContainer.source
-                            superTypeRefs.mapTo(this.superTypeRefs) { it as FirResolvedTypeRef }
-                        }
+                        val types = components.findTypesForSuperCandidates(superTypeRefs, containingCall)
+                        if (types.size == 1)
+                            buildResolvedTypeRef {
+                                source = superReferenceContainer.source?.fakeElement(FirFakeSourceElementKind.SuperCallImplicitType)
+                                type = types.single()
+                            }
+                        else
+                            buildErrorTypeRef {
+                                source = superReferenceContainer.source
+                                // NB: NOT_A_SUPERTYPE is reported by a separate checker
+                                diagnostic = ConeStubDiagnostic(ConeSimpleDiagnostic("Ambiguous supertype", DiagnosticKind.Other))
+                            }
                     }
                 }
                 superReferenceContainer.resultType = resultType

compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirSourceElement.kt

@@ -138,6 +138,10 @@ sealed class FirFakeSourceElementKind : FirSourceElementKind() {
     // a ?: b --> when(val $subj = a) { .... }
     // where `val $subj = a` has a fake source
     object WhenGeneratedSubject : FirFakeSourceElementKind()
+
+    // super.foo() --> super<Supertype>.foo()
+    // where `Supertype` has a fake source
+    object SuperCallImplicitType : FirFakeSourceElementKind()
 }
 
 sealed class FirSourceElement {