Private setter for open property: take containing class modality into account #KT-10325 Fixed

compiler/frontend/src/org/jetbrains/kotlin/resolve/DeclarationsChecker.kt

@@ -681,14 +681,17 @@ class DeclarationsChecker(
             }
         }
         else {
-            if (propertyDescriptor.modality != Modality.FINAL
+            if (propertyDescriptor.isOverridable
                 && accessorDescriptor.visibility == Visibilities.PRIVATE
                 && propertyDescriptor.visibility != Visibilities.PRIVATE) {
                 if (propertyDescriptor.modality == Modality.ABSTRACT) {
                     reportVisibilityModifierDiagnostics(tokens.values, Errors.PRIVATE_SETTER_FOR_ABSTRACT_PROPERTY)
                 }
                 else {
-                    reportVisibilityModifierDiagnostics(tokens.values, Errors.PRIVATE_SETTER_FOR_OPEN_PROPERTY)
+                    val parentDescriptor = propertyDescriptor.containingDeclaration
+                    if (parentDescriptor !is ClassDescriptor || !parentDescriptor.isFinal) {
+                        reportVisibilityModifierDiagnostics(tokens.values, Errors.PRIVATE_SETTER_FOR_OPEN_PROPERTY)
+                    }
                 }
             }
             else if (propertyDescriptor.isLateInit && accessorDescriptor.visibility != propertyDescriptor.visibility) {

compiler/testData/diagnostics/tests/OverridenSetterVisibility.kt

@@ -13,7 +13,7 @@ abstract class ATest {
 class Test: ATest(), ITest {
     override var prop : Int
         get() = 12
-        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE, PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set(value) {}
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE!>private<!> set(value) {}
 
     override var prop2 : Int
         get() = 14

compiler/testData/diagnostics/tests/PrivateSetterForOverridden.kt

@@ -0,0 +1,70 @@
+// See KT-10325: private setters are allowed for overridden properties in final class
+
+interface A {
+    val a: Int
+
+    var b: Int
+}
+
+abstract class AA {
+    abstract val c: Int
+
+    abstract var d: Int
+}
+
+class B : A, AA() {
+    override var a: Int = 0
+        // Ok
+        private set
+
+    override var b: Int = 1
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE!>private<!> set
+
+    override var c: Int = 2
+        // Ok
+        private set
+
+    override var d: Int = 3
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE!>private<!> set
+}
+
+open class C : A, AA() {
+    override var a: Int = 0
+        // Errors here and below
+        <!PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+
+    override var b: Int = 1
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE, PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+
+    override var c: Int = 2
+        <!PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+
+    override var d: Int = 3
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE, PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+}
+
+abstract class D : A, AA() {
+    override var a: Int = 0
+        // Errors here and below
+        <!PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+
+    override var b: Int = 1
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE, PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+
+    override var c: Int = 2
+        <!PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+
+    override var d: Int = 3
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE, PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set
+}
+
+interface E : A {
+    override var a: Int
+        get() = 0
+        // Errors here and below
+        <!PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set(arg) {}
+
+    override var b: Int
+        get() = 0
+        <!CANNOT_WEAKEN_ACCESS_PRIVILEGE, PRIVATE_SETTER_FOR_OPEN_PROPERTY!>private<!> set(arg) {}
+}

compiler/testData/diagnostics/tests/PrivateSetterForOverridden.txt

@@ -0,0 +1,59 @@
+package
+
+public interface A {
+    public abstract val a: kotlin.Int
+    public abstract var b: kotlin.Int
+    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
+}
+
+public abstract class AA {
+    public constructor AA()
+    public abstract val c: kotlin.Int
+    public abstract var d: kotlin.Int
+    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
+}
+
+public final class B : A, AA {
+    public constructor B()
+    public open override /*1*/ var a: kotlin.Int
+    public open override /*1*/ var b: kotlin.Int
+    public open override /*1*/ var c: kotlin.Int
+    public open override /*1*/ var d: kotlin.Int
+    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*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class C : A, AA {
+    public constructor C()
+    public open override /*1*/ var a: kotlin.Int
+    public open override /*1*/ var b: kotlin.Int
+    public open override /*1*/ var c: kotlin.Int
+    public open override /*1*/ var d: kotlin.Int
+    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*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public abstract class D : A, AA {
+    public constructor D()
+    public open override /*1*/ var a: kotlin.Int
+    public open override /*1*/ var b: kotlin.Int
+    public open override /*1*/ var c: kotlin.Int
+    public open override /*1*/ var d: kotlin.Int
+    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*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface E : A {
+    public open override /*1*/ var a: kotlin.Int
+    public open override /*1*/ var b: kotlin.Int
+    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/DiagnosticsTestGenerated.java

@@ -499,6 +499,12 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
             doTest(fileName);
         }
 
+        @TestMetadata("PrivateSetterForOverridden.kt")
+        public void testPrivateSetterForOverridden() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/PrivateSetterForOverridden.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("ProcessingEmptyImport.kt")
         public void testProcessingEmptyImport() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/ProcessingEmptyImport.kt");