[FE 1.0] Implement deprecation warning for private constructors of sealed classes

^KT-44866
^KT-49729 Fixed

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java

@@ -26407,6 +26407,18 @@ public class DiagnosisCompilerTestFE10TestdataTestGenerated extends AbstractDiag
                 runTest("compiler/testData/diagnostics/tests/sealed/OperationWhen.kt");
             }
 
+            @Test
+            @TestMetadata("privateSealedConstructors_error.kt")
+            public void testPrivateSealedConstructors_error() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_error.kt");
+            }
+
+            @Test
+            @TestMetadata("privateSealedConstructors_warning.kt")
+            public void testPrivateSealedConstructors_warning() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_warning.kt");
+            }
+
             @Test
             @TestMetadata("privateTypeInConstructor.kt")
             public void testPrivateTypeInConstructor() throws Exception {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java

@@ -26407,6 +26407,18 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirDiagnosti
                 runTest("compiler/testData/diagnostics/tests/sealed/OperationWhen.kt");
             }
 
+            @Test
+            @TestMetadata("privateSealedConstructors_error.kt")
+            public void testPrivateSealedConstructors_error() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_error.kt");
+            }
+
+            @Test
+            @TestMetadata("privateSealedConstructors_warning.kt")
+            public void testPrivateSealedConstructors_warning() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_warning.kt");
+            }
+
             @Test
             @TestMetadata("privateTypeInConstructor.kt")
             public void testPrivateTypeInConstructor() throws Exception {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java

@@ -26407,6 +26407,18 @@ public class FirOldFrontendDiagnosticsWithLightTreeTestGenerated extends Abstrac
                 runTest("compiler/testData/diagnostics/tests/sealed/OperationWhen.kt");
             }
 
+            @Test
+            @TestMetadata("privateSealedConstructors_error.kt")
+            public void testPrivateSealedConstructors_error() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_error.kt");
+            }
+
+            @Test
+            @TestMetadata("privateSealedConstructors_warning.kt")
+            public void testPrivateSealedConstructors_warning() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_warning.kt");
+            }
+
             @Test
             @TestMetadata("privateTypeInConstructor.kt")
             public void testPrivateTypeInConstructor() throws Exception {

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -810,6 +810,8 @@ public interface Errors {
 
     DiagnosticFactory0<KtParenthesizedExpression> PARENTHESIZED_COMPANION_LHS_DEPRECATION = DiagnosticFactory0.create(WARNING);
 
+    DiagnosticFactory0<PsiElement> RESOLUTION_TO_PRIVATE_CONSTRUCTOR_OF_SEALED_CLASS = DiagnosticFactory0.create(WARNING);
+
     // Type inference
 
     DiagnosticFactory0<KtParameter> CANNOT_INFER_PARAMETER_TYPE = DiagnosticFactory0.create(ERROR);

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -450,6 +450,8 @@ public class DefaultErrorMessages {
 
         MAP.put(PARENTHESIZED_COMPANION_LHS_DEPRECATION, "Access to companion object through parenthesized class name is deprecated. Please, add explicit Companion qualifier.");
 
+        MAP.put(RESOLUTION_TO_PRIVATE_CONSTRUCTOR_OF_SEALED_CLASS, "Resolution to private constructor of sealed class. In future it will be allowed to use this constructor only inside declaring sealed class");
+
         MAP.put(LOCAL_EXTENSION_PROPERTY, "Local extension properties are not allowed");
         MAP.put(LOCAL_VARIABLE_WITH_GETTER, "Local variables are not allowed to have getters");
         MAP.put(LOCAL_VARIABLE_WITH_SETTER, "Local variables are not allowed to have setters");

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

@@ -63,6 +63,7 @@ private val DEFAULT_CALL_CHECKERS = listOf(
     UnitConversionCallChecker, FunInterfaceConstructorReferenceChecker, NullableExtensionOperatorWithSafeCallChecker,
     ReferencingToUnderscoreNamedParameterOfCatchBlockChecker, VarargWrongExecutionOrderChecker, SelfCallInNestedObjectConstructorChecker,
     NewSchemeOfIntegerOperatorResolutionChecker, EnumEntryVsCompanionPriorityCallChecker, CompanionInParenthesesLHSCallChecker,
+    ResolutionToPrivateConstructorOfSealedClassChecker,
 )
 private val DEFAULT_TYPE_CHECKERS = emptyList<AdditionalTypeChecker>()
 private val DEFAULT_CLASSIFIER_USAGE_CHECKERS = listOf(

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/ResolutionToPrivateConstructorOfSealedClassChecker.kt

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2010-2021 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.resolve.calls.checkers
+
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.config.LanguageFeature
+import org.jetbrains.kotlin.descriptors.ConstructorDescriptor
+import org.jetbrains.kotlin.descriptors.DescriptorVisibilities
+import org.jetbrains.kotlin.descriptors.isSealed
+import org.jetbrains.kotlin.diagnostics.Errors
+import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
+
+object ResolutionToPrivateConstructorOfSealedClassChecker : CallChecker {
+    override fun check(resolvedCall: ResolvedCall<*>, reportOn: PsiElement, context: CallCheckerContext) {
+        // If AllowSealedInheritorsInDifferentFilesOfSamePackage disabled then all sealed constructors are private by default
+        if (!context.languageVersionSettings.supportsFeature(LanguageFeature.AllowSealedInheritorsInDifferentFilesOfSamePackage)) return
+        if (context.languageVersionSettings.supportsFeature(LanguageFeature.UseConsistentRulesForPrivateConstructorsOfSealedClasses)) return
+        val descriptor = resolvedCall.resultingDescriptor as? ConstructorDescriptor ?: return
+        if (descriptor.visibility != DescriptorVisibilities.PRIVATE) return
+        if (!descriptor.constructedClass.isSealed()) return
+        val containingDescriptor = context.scope.ownerDescriptor
+        val receiver = resolvedCall.dispatchReceiver ?: DescriptorVisibilities.ALWAYS_SUITABLE_RECEIVER
+        if (DescriptorVisibilities.findInvisibleMember(receiver, descriptor, containingDescriptor, false) != null) {
+            context.trace.report(Errors.RESOLUTION_TO_PRIVATE_CONSTRUCTOR_OF_SEALED_CLASS.on(reportOn))
+        }
+    }
+}

compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_error.fir.kt

@@ -0,0 +1,21 @@
+// LANGUAGE: +UseConsistentRulesForPrivateConstructorsOfSealedClasses
+// ISSUE: KT-44866, KT-49729
+
+// FILE: base.kt
+sealed class SealedBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class SealedNested : SealedBase("nested")
+}
+class SealedOuter : SealedBase(<!ARGUMENT_TYPE_MISMATCH!>"outer"<!>)
+
+abstract class RegularBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class RegularNested : RegularBase("nested")
+}
+class RegularOuter : RegularBase(<!ARGUMENT_TYPE_MISMATCH!>"outer"<!>)
+
+// FILE: derived.kt
+
+class SealedOuterInDifferentFile : SealedBase(<!ARGUMENT_TYPE_MISMATCH!>"other file"<!>)

compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_error.kt

@@ -0,0 +1,21 @@
+// LANGUAGE: +UseConsistentRulesForPrivateConstructorsOfSealedClasses
+// ISSUE: KT-44866, KT-49729
+
+// FILE: base.kt
+sealed class SealedBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class SealedNested : SealedBase("nested")
+}
+class SealedOuter : <!INVISIBLE_MEMBER!>SealedBase<!>("outer")
+
+abstract class RegularBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class RegularNested : RegularBase("nested")
+}
+class RegularOuter : <!INVISIBLE_MEMBER!>RegularBase<!>("outer")
+
+// FILE: derived.kt
+
+class SealedOuterInDifferentFile : <!INVISIBLE_MEMBER!>SealedBase<!>("other file")

compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_error.txt

@@ -0,0 +1,53 @@
+package
+
+public abstract class RegularBase {
+    public constructor RegularBase(/*0*/ x: kotlin.Int)
+    private constructor RegularBase(/*0*/ y: kotlin.String)
+    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 RegularNested : RegularBase {
+        public constructor RegularNested()
+        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 RegularOuter : RegularBase {
+    public constructor RegularOuter()
+    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 sealed class SealedBase {
+    protected constructor SealedBase(/*0*/ x: kotlin.Int)
+    private constructor SealedBase(/*0*/ y: kotlin.String)
+    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 SealedNested : SealedBase {
+        public constructor SealedNested()
+        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 SealedOuter : SealedBase {
+    public constructor SealedOuter()
+    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 SealedOuterInDifferentFile : SealedBase {
+    public constructor SealedOuterInDifferentFile()
+    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/testData/diagnostics/tests/sealed/privateSealedConstructors_warning.fir.kt

@@ -0,0 +1,21 @@
+// LANGUAGE: -UseConsistentRulesForPrivateConstructorsOfSealedClasses
+// ISSUE: KT-44866, KT-49729
+
+// FILE: base.kt
+sealed class SealedBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class SealedNested : SealedBase("nested")
+}
+class SealedOuter : SealedBase(<!ARGUMENT_TYPE_MISMATCH!>"outer"<!>)
+
+abstract class RegularBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class RegularNested : RegularBase("nested")
+}
+class RegularOuter : RegularBase(<!ARGUMENT_TYPE_MISMATCH!>"outer"<!>)
+
+// FILE: derived.kt
+
+class SealedOuterInDifferentFile : SealedBase(<!ARGUMENT_TYPE_MISMATCH!>"other file"<!>)

compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_warning.kt

@@ -0,0 +1,21 @@
+// LANGUAGE: -UseConsistentRulesForPrivateConstructorsOfSealedClasses
+// ISSUE: KT-44866, KT-49729
+
+// FILE: base.kt
+sealed class SealedBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class SealedNested : SealedBase("nested")
+}
+class SealedOuter : <!RESOLUTION_TO_PRIVATE_CONSTRUCTOR_OF_SEALED_CLASS!>SealedBase<!>("outer")
+
+abstract class RegularBase(x: Int) {
+    private constructor(y: String) : this(y.length)
+
+    class RegularNested : RegularBase("nested")
+}
+class RegularOuter : <!INVISIBLE_MEMBER!>RegularBase<!>("outer")
+
+// FILE: derived.kt
+
+class SealedOuterInDifferentFile : <!INVISIBLE_MEMBER, RESOLUTION_TO_PRIVATE_CONSTRUCTOR_OF_SEALED_CLASS!>SealedBase<!>("other file")

compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_warning.txt

@@ -0,0 +1,53 @@
+package
+
+public abstract class RegularBase {
+    public constructor RegularBase(/*0*/ x: kotlin.Int)
+    private constructor RegularBase(/*0*/ y: kotlin.String)
+    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 RegularNested : RegularBase {
+        public constructor RegularNested()
+        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 RegularOuter : RegularBase {
+    public constructor RegularOuter()
+    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 sealed class SealedBase {
+    protected constructor SealedBase(/*0*/ x: kotlin.Int)
+    private constructor SealedBase(/*0*/ y: kotlin.String)
+    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 SealedNested : SealedBase {
+        public constructor SealedNested()
+        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 SealedOuter : SealedBase {
+    public constructor SealedOuter()
+    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 SealedOuterInDifferentFile : SealedBase {
+    public constructor SealedOuterInDifferentFile()
+    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/testData/diagnostics/tests/sealed/protectedConstructors_disabled.fir.kt

@@ -22,7 +22,7 @@ sealed class Case3 private constructor(val x: Int) {
     class Inheritor2 : Case3("Hello")
 }
 
-class Case3Inheritor3 : Case3(<!ARGUMENT_TYPE_MISMATCH!>20<!>) // should be an error in 1.6 (?)
+class Case3Inheritor3 : Case3(<!ARGUMENT_TYPE_MISMATCH!>20<!>) // should be an error in 1.8
 
 sealed class Case4 {
     protected constructor(x: Int)

compiler/testData/diagnostics/tests/sealed/protectedConstructors_disabled.kt

@@ -22,7 +22,7 @@ sealed class Case3 private constructor(val x: Int) {
     class Inheritor2 : Case3("Hello")
 }
 
-class Case3Inheritor3 : Case3(20) // should be an error in 1.6 (?)
+class Case3Inheritor3 : Case3(20) // should be an error in 1.8
 
 sealed class Case4 {
     <!NON_PRIVATE_CONSTRUCTOR_IN_SEALED!>protected<!> constructor(x: Int)

compiler/testData/diagnostics/tests/sealed/protectedConstructors_enabled.fir.kt

@@ -22,7 +22,7 @@ sealed class Case3 private constructor(val x: Int) {
     class Inheritor2 : Case3("Hello")
 }
 
-class Case3Inheritor3 : Case3(<!ARGUMENT_TYPE_MISMATCH!>20<!>) // should be an error in 1.6 (?)
+class Case3Inheritor3 : Case3(<!ARGUMENT_TYPE_MISMATCH!>20<!>) // should be an error in 1.8
 
 sealed class Case4 {
     protected constructor(x: Int)

compiler/testData/diagnostics/tests/sealed/protectedConstructors_enabled.kt

@@ -22,7 +22,7 @@ sealed class Case3 private constructor(val x: Int) {
     class Inheritor2 : Case3("Hello")
 }
 
-class Case3Inheritor3 : Case3(20) // should be an error in 1.6 (?)
+class Case3Inheritor3 : <!RESOLUTION_TO_PRIVATE_CONSTRUCTOR_OF_SEALED_CLASS!>Case3<!>(20) // should be an error in 1.8
 
 sealed class Case4 {
     protected constructor(x: Int)

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java

@@ -26497,6 +26497,18 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/sealed/OperationWhen.kt");
             }
 
+            @Test
+            @TestMetadata("privateSealedConstructors_error.kt")
+            public void testPrivateSealedConstructors_error() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_error.kt");
+            }
+
+            @Test
+            @TestMetadata("privateSealedConstructors_warning.kt")
+            public void testPrivateSealedConstructors_warning() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/sealed/privateSealedConstructors_warning.kt");
+            }
+
             @Test
             @TestMetadata("privateTypeInConstructor.kt")
             public void testPrivateTypeInConstructor() throws Exception {