Introduce warning for secondary constructor in enums without delegation to primary constructors (KT-35870)

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

@@ -7612,6 +7612,16 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirOldFronte
             runTest("compiler/testData/diagnostics/tests/enum/SecondaryConstructorCall.kt");
         }
 
+        @TestMetadata("secondaryConstructorWithoutDelegatingToPrimaryOne.kt")
+        public void testSecondaryConstructorWithoutDelegatingToPrimaryOne() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOne.kt");
+        }
+
+        @TestMetadata("secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.kt")
+        public void testSecondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.kt");
+        }
+
         @TestMetadata("starImportNestedClassAndEntries.kt")
         public void testStarImportNestedClassAndEntries() throws Exception {
             runTest("compiler/testData/diagnostics/tests/enum/starImportNestedClassAndEntries.kt");

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

@@ -388,6 +388,9 @@ public interface Errors {
     DiagnosticFactory0<KtConstructorDelegationCall> PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED =
             DiagnosticFactory0.create(ERROR, PositioningStrategies.SECONDARY_CONSTRUCTOR_DELEGATION_CALL);
 
+    DiagnosticFactory0<KtConstructorDelegationCall> PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED_IN_ENUM =
+            DiagnosticFactory0.create(WARNING, PositioningStrategies.SECONDARY_CONSTRUCTOR_DELEGATION_CALL);
+
     DiagnosticFactory0<KtConstructorDelegationReferenceExpression> DELEGATION_SUPER_CALL_IN_ENUM_CONSTRUCTOR =
             DiagnosticFactory0.create(ERROR);
 

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

@@ -634,6 +634,7 @@ public class DefaultErrorMessages {
         MAP.put(CONSTRUCTOR_IN_OBJECT, "Constructors are not allowed for objects");
         MAP.put(SUPERTYPE_INITIALIZED_WITHOUT_PRIMARY_CONSTRUCTOR, "Supertype initialization is impossible without primary constructor");
         MAP.put(PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED, "Primary constructor call expected");
+        MAP.put(PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED_IN_ENUM, "Primary constructor call expected. It's going to be an error in 1.5.");
         MAP.put(DELEGATION_SUPER_CALL_IN_ENUM_CONSTRUCTOR, "Call to super is not allowed in enum constructor");
         MAP.put(PRIMARY_CONSTRUCTOR_REQUIRED_FOR_DATA_CLASS, "Primary constructor required for data class");
         MAP.put(EXPLICIT_DELEGATION_CALL_REQUIRED,

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallResolver.java

@@ -17,6 +17,7 @@ import org.jetbrains.kotlin.config.LanguageFeature;
 import org.jetbrains.kotlin.config.LanguageVersionSettings;
 import org.jetbrains.kotlin.descriptors.*;
 import org.jetbrains.kotlin.descriptors.annotations.Annotations;
+import org.jetbrains.kotlin.diagnostics.DiagnosticFactory0;
 import org.jetbrains.kotlin.name.Name;
 import org.jetbrains.kotlin.progress.ProgressIndicatorAndCompilationCanceledStatus;
 import org.jetbrains.kotlin.psi.*;
@@ -334,8 +335,12 @@ public class CallResolver {
             KtConstructorDelegationCall delegationCall = (KtConstructorDelegationCall) context.call.getCallElement();
             DeclarationDescriptor container = context.scope.getOwnerDescriptor();
             assert container instanceof ConstructorDescriptor : "Trying to resolve JetConstructorDelegationCall not in constructor. scope.ownerDescriptor = " + container;
-            return (OverloadResolutionResults) resolveConstructorDelegationCall(context, delegationCall, (KtConstructorDelegationReferenceExpression) calleeExpression,
-                                                    (ClassConstructorDescriptor) container);
+            return (OverloadResolutionResults) resolveConstructorDelegationCall(
+                    context,
+                    delegationCall,
+                    (KtConstructorDelegationReferenceExpression) calleeExpression,
+                    (ClassDescriptor) container.getContainingDeclaration()
+            );
         }
         else if (calleeExpression == null) {
             return checkArgumentTypesAndFail(context);
@@ -433,18 +438,28 @@ public class CallResolver {
                 dataFlowValueFactory,
                 InferenceSession.Companion.getDefault());
 
-        if (call.getCalleeExpression() == null) return checkArgumentTypesAndFail(context);
+        KtConstructorDelegationReferenceExpression calleeExpression = call.getCalleeExpression();
+
+        if (calleeExpression == null) return checkArgumentTypesAndFail(context);
+
+        ClassDescriptor currentClassDescriptor = constructorDescriptor.getContainingDeclaration();
 
         if (constructorDescriptor.getConstructedClass().getKind() == ClassKind.ENUM_CLASS && call.isImplicit()) {
+            if (currentClassDescriptor.getUnsubstitutedPrimaryConstructor() != null) {
+                DiagnosticFactory0<KtConstructorDelegationCall> warningOrError;
+
+                if (languageVersionSettings.supportsFeature(LanguageFeature.RequiredPrimaryConstructorDelegationCallInEnums)) {
+                    warningOrError = PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED; // error
+                } else {
+                    warningOrError = PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED_IN_ENUM; // warning
+                }
+
+                context.trace.report(warningOrError.on((KtConstructorDelegationCall) calleeExpression.getParent()));
+            }
             return null;
         }
 
-        return resolveConstructorDelegationCall(
-                context,
-                call,
-                call.getCalleeExpression(),
-                constructorDescriptor
-        );
+        return resolveConstructorDelegationCall(context, call, call.getCalleeExpression(), currentClassDescriptor);
     }
 
     @NotNull
@@ -452,12 +467,10 @@ public class CallResolver {
             @NotNull BasicCallResolutionContext context,
             @NotNull KtConstructorDelegationCall call,
             @NotNull KtConstructorDelegationReferenceExpression calleeExpression,
-            @NotNull ClassConstructorDescriptor calleeConstructor
+            @NotNull ClassDescriptor currentClassDescriptor
     ) {
         context.trace.record(BindingContext.LEXICAL_SCOPE, call, context.scope);
 
-        ClassDescriptor currentClassDescriptor = calleeConstructor.getContainingDeclaration();
-
         boolean isThisCall = calleeExpression.isThis();
         if (currentClassDescriptor.getKind() == ClassKind.ENUM_CLASS && !isThisCall) {
             context.trace.report(DELEGATION_SUPER_CALL_IN_ENUM_CONSTRUCTOR.on(calleeExpression));
@@ -484,9 +497,8 @@ public class CallResolver {
         }
 
 
-        KotlinType superType = isThisCall ?
-                                  calleeConstructor.getContainingDeclaration().getDefaultType() :
-                                  DescriptorUtils.getSuperClassType(currentClassDescriptor);
+        KotlinType superType =
+                isThisCall ? currentClassDescriptor.getDefaultType() : DescriptorUtils.getSuperClassType(currentClassDescriptor);
 
         Pair<Collection<ResolutionCandidate<ConstructorDescriptor>>, BasicCallResolutionContext> candidatesAndContext =
                 prepareCandidatesAndContextForConstructorCall(superType, context, syntheticScopes);

compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOne.fir.kt

@@ -0,0 +1,43 @@
+// DIAGNOSTICS: -UNUSED_PARAMETER
+// !LANGUAGE: -RequiredPrimaryConstructorDelegationCallInEnums
+
+enum class Enum1(val a: String) {
+    A;
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor()<!>
+}
+
+enum class Enum2(val a: String) {
+    A, B;
+    constructor(): this("")
+}
+
+enum class Enum3(val a: String = "") {
+    A, B, C;
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor()<!>
+}
+
+enum class Enum4(val a: String = "") {
+    A, B, C;
+    constructor(): <!CYCLIC_CONSTRUCTOR_DELEGATION_CALL!>this<!>()
+}
+
+enum class Enum5(val a: String = "") {
+    A, B, C;
+    constructor(): this(a = "")
+}
+
+enum class Enum6(val a: String = "") {
+    A, B, C;
+}
+
+enum class Enum7(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    constructor(x: Int): this("")
+}
+
+enum class Enum8(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor(x: Int)<!>
+}

compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOne.kt

@@ -0,0 +1,43 @@
+// DIAGNOSTICS: -UNUSED_PARAMETER
+// !LANGUAGE: -RequiredPrimaryConstructorDelegationCallInEnums
+
+enum class Enum1(val a: String) {
+    A;
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED_IN_ENUM!>constructor()<!>
+}
+
+enum class Enum2(val a: String) {
+    A, B;
+    constructor(): this("")
+}
+
+enum class Enum3(val a: String = "") {
+    <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>A,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>B,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>C;<!>
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED_IN_ENUM!>constructor()<!>
+}
+
+enum class Enum4(val a: String = "") {
+    <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>A,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>B,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>C;<!>
+    constructor(): <!CYCLIC_CONSTRUCTOR_DELEGATION_CALL!>this<!>()
+}
+
+enum class Enum5(val a: String = "") {
+    <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>A,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>B,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>C;<!>
+    constructor(): this(a = "")
+}
+
+enum class Enum6(val a: String = "") {
+    A, B, C;
+}
+
+enum class Enum7(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    constructor(x: Int): this("")
+}
+
+enum class Enum8(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED_IN_ENUM!>constructor(x: Int)<!>
+}

compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOne.txt

@@ -0,0 +1,196 @@
+package
+
+public final enum class Enum1 : kotlin.Enum<Enum1> {
+    enum entry A
+
+    private constructor Enum1()
+    private constructor Enum1(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum1): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum1!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum1
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum1>
+}
+
+public final enum class Enum2 : kotlin.Enum<Enum2> {
+    enum entry A
+
+    enum entry B
+
+    private constructor Enum2()
+    private constructor Enum2(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum2): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum2!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum2
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum2>
+}
+
+public final enum class Enum3 : kotlin.Enum<Enum3> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum3()
+    private constructor Enum3(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum3): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum3!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum3
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum3>
+}
+
+public final enum class Enum4 : kotlin.Enum<Enum4> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum4()
+    private constructor Enum4(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum4): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum4!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum4
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum4>
+}
+
+public final enum class Enum5 : kotlin.Enum<Enum5> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum5()
+    private constructor Enum5(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum5): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum5!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum5
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum5>
+}
+
+public final enum class Enum6 : kotlin.Enum<Enum6> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum6(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum6): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum6!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum6
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum6>
+}
+
+public final enum class Enum7 : kotlin.Enum<Enum7> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum7()
+    private constructor Enum7(/*0*/ x: kotlin.Int)
+    private constructor Enum7(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum7): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum7!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum7
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum7>
+}
+
+public final enum class Enum8 : kotlin.Enum<Enum8> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum8()
+    private constructor Enum8(/*0*/ x: kotlin.Int)
+    private constructor Enum8(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum8): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum8!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum8
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum8>
+}

compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.fir.kt

@@ -0,0 +1,43 @@
+// DIAGNOSTICS: -UNUSED_PARAMETER
+// !LANGUAGE: +RequiredPrimaryConstructorDelegationCallInEnums
+
+enum class Enum1(val a: String) {
+    A;
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor()<!>
+}
+
+enum class Enum2(val a: String) {
+    A, B;
+    constructor(): this("")
+}
+
+enum class Enum3(val a: String = "") {
+    A, B, C;
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor()<!>
+}
+
+enum class Enum4(val a: String = "") {
+    A, B, C;
+    constructor(): <!CYCLIC_CONSTRUCTOR_DELEGATION_CALL!>this<!>()
+}
+
+enum class Enum5(val a: String = "") {
+    A, B, C;
+    constructor(): this(a = "")
+}
+
+enum class Enum6(val a: String = "") {
+    A, B, C;
+}
+
+enum class Enum7(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    constructor(x: Int): this("")
+}
+
+enum class Enum8(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor(x: Int)<!>
+}

compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.kt

@@ -0,0 +1,43 @@
+// DIAGNOSTICS: -UNUSED_PARAMETER
+// !LANGUAGE: +RequiredPrimaryConstructorDelegationCallInEnums
+
+enum class Enum1(val a: String) {
+    A;
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor()<!>
+}
+
+enum class Enum2(val a: String) {
+    A, B;
+    constructor(): this("")
+}
+
+enum class Enum3(val a: String = "") {
+    <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>A,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>B,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>C;<!>
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor()<!>
+}
+
+enum class Enum4(val a: String = "") {
+    <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>A,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>B,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>C;<!>
+    constructor(): <!CYCLIC_CONSTRUCTOR_DELEGATION_CALL!>this<!>()
+}
+
+enum class Enum5(val a: String = "") {
+    <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>A,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>B,<!> <!ENUM_ENTRY_SHOULD_BE_INITIALIZED!>C;<!>
+    constructor(): this(a = "")
+}
+
+enum class Enum6(val a: String = "") {
+    A, B, C;
+}
+
+enum class Enum7(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    constructor(x: Int): this("")
+}
+
+enum class Enum8(val a: String) {
+    A, B, C;
+    constructor(): this(10)
+    <!PRIMARY_CONSTRUCTOR_DELEGATION_CALL_EXPECTED!>constructor(x: Int)<!>
+}

compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.txt

@@ -0,0 +1,196 @@
+package
+
+public final enum class Enum1 : kotlin.Enum<Enum1> {
+    enum entry A
+
+    private constructor Enum1()
+    private constructor Enum1(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum1): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum1!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum1
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum1>
+}
+
+public final enum class Enum2 : kotlin.Enum<Enum2> {
+    enum entry A
+
+    enum entry B
+
+    private constructor Enum2()
+    private constructor Enum2(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum2): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum2!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum2
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum2>
+}
+
+public final enum class Enum3 : kotlin.Enum<Enum3> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum3()
+    private constructor Enum3(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum3): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum3!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum3
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum3>
+}
+
+public final enum class Enum4 : kotlin.Enum<Enum4> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum4()
+    private constructor Enum4(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum4): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum4!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum4
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum4>
+}
+
+public final enum class Enum5 : kotlin.Enum<Enum5> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum5()
+    private constructor Enum5(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum5): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum5!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum5
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum5>
+}
+
+public final enum class Enum6 : kotlin.Enum<Enum6> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum6(/*0*/ a: kotlin.String = ...)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum6): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum6!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum6
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum6>
+}
+
+public final enum class Enum7 : kotlin.Enum<Enum7> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum7()
+    private constructor Enum7(/*0*/ x: kotlin.Int)
+    private constructor Enum7(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum7): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum7!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum7
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum7>
+}
+
+public final enum class Enum8 : kotlin.Enum<Enum8> {
+    enum entry A
+
+    enum entry B
+
+    enum entry C
+
+    private constructor Enum8()
+    private constructor Enum8(/*0*/ x: kotlin.Int)
+    private constructor Enum8(/*0*/ a: kotlin.String)
+    public final val a: kotlin.String
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Enum8): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<Enum8!>!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Enum8
+    public final /*synthesized*/ fun values(): kotlin.Array<Enum8>
+}

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

@@ -7619,6 +7619,16 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTestWithFirVali
                 runTest("compiler/testData/diagnostics/tests/enum/SecondaryConstructorCall.kt");
             }
 
+            @TestMetadata("secondaryConstructorWithoutDelegatingToPrimaryOne.kt")
+            public void testSecondaryConstructorWithoutDelegatingToPrimaryOne() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOne.kt");
+            }
+
+            @TestMetadata("secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.kt")
+            public void testSecondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.kt");
+            }
+
             @TestMetadata("starImportNestedClassAndEntries.kt")
             public void testStarImportNestedClassAndEntries() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/enum/starImportNestedClassAndEntries.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java

@@ -7614,6 +7614,16 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                 runTest("compiler/testData/diagnostics/tests/enum/SecondaryConstructorCall.kt");
             }
 
+            @TestMetadata("secondaryConstructorWithoutDelegatingToPrimaryOne.kt")
+            public void testSecondaryConstructorWithoutDelegatingToPrimaryOne() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOne.kt");
+            }
+
+            @TestMetadata("secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.kt")
+            public void testSecondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/enum/secondaryConstructorWithoutDelegatingToPrimaryOneWithEnabledFeature.kt");
+            }
+
             @TestMetadata("starImportNestedClassAndEntries.kt")
             public void testStarImportNestedClassAndEntries() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/enum/starImportNestedClassAndEntries.kt");

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -136,6 +136,7 @@ enum class LanguageFeature(
     AdaptedCallableReferenceAgainstReflectiveType(KOTLIN_1_5, defaultState = LanguageFeature.State.DISABLED),
     ProhibitUsingNullableTypeParameterAgainstNotNullAnnotated(KOTLIN_1_5, kind = BUG_FIX),
     InferenceCompatibility(KOTLIN_1_5, kind = BUG_FIX),
+    RequiredPrimaryConstructorDelegationCallInEnums(KOTLIN_1_5, kind = BUG_FIX),
 
     // Temporarily disabled, see KT-27084/KT-22379
     SoundSmartcastFromLoopConditionForLoopAssignedVariables(sinceVersion = null, kind = BUG_FIX),