Redundant override inspection: don't report for ambiguous derivation

#KT-24405 Fixed
#KT-25883 Fixed

idea/src/org/jetbrains/kotlin/idea/inspections/KotlinRedundantOverrideInspection.kt

@@ -8,13 +8,16 @@ package org.jetbrains.kotlin.idea.inspections
 import com.intellij.codeInspection.*
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.util.TextRange
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.lexer.KtTokens
+import org.jetbrains.kotlin.load.java.descriptors.JavaMethodDescriptor
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.*
 import org.jetbrains.kotlin.resolve.BindingContext
-import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
-import org.jetbrains.kotlin.types.typeUtil.isSubtypeOf
 
 class KotlinRedundantOverrideInspection : AbstractKotlinInspection(), CleanupLocalInspectionTool {
     override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean, session: LocalInspectionToolSession) =
@@ -49,7 +52,7 @@ class KotlinRedundantOverrideInspection : AbstractKotlinInspection(), CleanupLoc
             val superCallElement = qualifiedExpression.selectorExpression as? KtCallElement ?: return
             if (!isSameFunctionName(superCallElement, function)) return
             if (!isSameArguments(superCallElement, function)) return
-            if (function.isDefinedInDelegatedSuperType(qualifiedExpression)) return
+            if (function.isAmbiguouslyDerived()) return
 
             val descriptor = holder.manager.createProblemDescriptor(
                 function,
@@ -90,23 +93,31 @@ class KotlinRedundantOverrideInspection : AbstractKotlinInspection(), CleanupLoc
     }
 }
 
-private fun KtNamedFunction.isDefinedInDelegatedSuperType(superQualifiedExpression: KtDotQualifiedExpression): Boolean {
+private fun KtNamedFunction.isAmbiguouslyDerived(): Boolean {
+    val context = analyze()
+    val original = context[BindingContext.FUNCTION, this]?.original
+    val overriddenDescriptors = original?.overriddenDescriptors ?: return false
+    if (overriddenDescriptors.size < 2) return false
+    // Two+ functions
+    // At least one default in interface or abstract in class, or just something from Java
+    if (overriddenDescriptors.any { overriddenFunction ->
+            overriddenFunction is JavaMethodDescriptor || when ((overriddenFunction.containingDeclaration as? ClassDescriptor)?.kind) {
+                ClassKind.CLASS -> overriddenFunction.modality == Modality.ABSTRACT
+                ClassKind.INTERFACE -> overriddenFunction.modality != Modality.ABSTRACT
+                else -> false
+            }
+
+        }
+    ) return true
+
     val delegatedSuperTypeEntries =
         containingClassOrObject?.superTypeListEntries?.filterIsInstance<KtDelegatedSuperTypeEntry>() ?: return false
     if (delegatedSuperTypeEntries.isEmpty()) return false
-
-    val context = superQualifiedExpression.analyze()
-    val delegatedSuperTypes = delegatedSuperTypeEntries.mapNotNull { entry ->
-        context[BindingContext.TYPE, entry.typeReference]
+    val delegatedSuperDeclarations = delegatedSuperTypeEntries.mapNotNull { entry ->
+        context[BindingContext.TYPE, entry.typeReference]?.constructor?.declarationDescriptor
     }
-
-    val superResolvedCall = superQualifiedExpression.getResolvedCall(context) ?: return false
-    val superCallResolvedDescriptor = superResolvedCall.resultingDescriptor
-    val superCallResolvedReceiverTypes = superCallResolvedDescriptor.overriddenDescriptors.mapNotNull { it.dispatchReceiverParameter?.type }
-
-    return delegatedSuperTypes.any { delegatedSuperType ->
-        superCallResolvedReceiverTypes.any { superCallReceiverType ->
-            delegatedSuperType.isSubtypeOf(superCallReceiverType)
-        }
+    return overriddenDescriptors.any {
+        it.containingDeclaration in delegatedSuperDeclarations
     }
 }
+

idea/testData/inspectionsLocal/redundantOverride/abstractClassAndInterface.kt

@@ -0,0 +1,13 @@
+// PROBLEM: none
+
+abstract class AbstractClass {
+    abstract fun foo(): Int
+}
+
+interface Interface {
+    fun foo(): Int = 3
+}
+
+class ChildClass : AbstractClass(), Interface {
+    override <caret>fun foo() = super.foo()
+}

idea/testData/inspectionsLocal/redundantOverride/boxedParameters.kt

@@ -0,0 +1,10 @@
+// PROBLEM: none
+// WITH_RUNTIME
+
+interface Foo {
+    fun add(i: Int): Boolean
+}
+
+class Bar: ArrayList<Int>(), Foo {
+    override <caret>fun add(i: Int) = super.add(i)
+}

idea/testData/inspectionsLocal/redundantOverride/classAndInterface.kt

@@ -0,0 +1,11 @@
+open class Class {
+    open fun foo(): Int = 4
+}
+
+interface Interface {
+    fun foo(): Int
+}
+
+class ChildClass : Class(), Interface {
+    override <caret>fun foo() = super.foo()
+}

idea/testData/inspectionsLocal/redundantOverride/classAndInterface.kt.after

@@ -0,0 +1,10 @@
+open class Class {
+    open fun foo(): Int = 4
+}
+
+interface Interface {
+    fun foo(): Int
+}
+
+class ChildClass : Class(), Interface {
+}

idea/testData/inspectionsLocal/redundantOverride/twoInterfaces.kt

@@ -0,0 +1,13 @@
+// PROBLEM: none
+
+interface Foo {
+    fun test()
+}
+
+interface Gav {
+    fun test() {}
+}
+
+class TwoInterfaces : Foo, Gav {
+    override <caret>fun test() = super.test()
+}

idea/tests/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java

@@ -4027,6 +4027,11 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             KotlinTestUtils.runTest(this::doTest, TargetBackend.ANY, testDataFilePath);
         }
 
+        @TestMetadata("abstractClassAndInterface.kt")
+        public void testAbstractClassAndInterface() throws Exception {
+            runTest("idea/testData/inspectionsLocal/redundantOverride/abstractClassAndInterface.kt");
+        }
+
         public void testAllFilesPresentInRedundantOverride() throws Exception {
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/inspectionsLocal/redundantOverride"), Pattern.compile("^([\\w\\-_]+)\\.(kt|kts)$"), TargetBackend.ANY, true);
         }
@@ -4051,11 +4056,21 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             runTest("idea/testData/inspectionsLocal/redundantOverride/basic.kt");
         }
 
+        @TestMetadata("boxedParameters.kt")
+        public void testBoxedParameters() throws Exception {
+            runTest("idea/testData/inspectionsLocal/redundantOverride/boxedParameters.kt");
+        }
+
         @TestMetadata("callDifferentSuperMethod.kt")
         public void testCallDifferentSuperMethod() throws Exception {
             runTest("idea/testData/inspectionsLocal/redundantOverride/callDifferentSuperMethod.kt");
         }
 
+        @TestMetadata("classAndInterface.kt")
+        public void testClassAndInterface() throws Exception {
+            runTest("idea/testData/inspectionsLocal/redundantOverride/classAndInterface.kt");
+        }
+
         @TestMetadata("dataClass.kt")
         public void testDataClass() throws Exception {
             runTest("idea/testData/inspectionsLocal/redundantOverride/dataClass.kt");
@@ -4101,6 +4116,11 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             runTest("idea/testData/inspectionsLocal/redundantOverride/singleExpressionFunction.kt");
         }
 
+        @TestMetadata("twoInterfaces.kt")
+        public void testTwoInterfaces() throws Exception {
+            runTest("idea/testData/inspectionsLocal/redundantOverride/twoInterfaces.kt");
+        }
+
         @TestMetadata("useGenericsSuper.kt")
         public void testUseGenericsSuper() throws Exception {
             runTest("idea/testData/inspectionsLocal/redundantOverride/useGenericsSuper.kt");