Implement additional declaration checks for inline classes

- Implementation by delegation is prohibited
- Delegated properties are prohibited

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

@@ -325,7 +325,9 @@ public interface Errors {
     DiagnosticFactory0<KtParameter> INLINE_CLASS_CONSTRUCTOR_NOT_FINAL_READ_ONLY_PARAMETER = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<PsiElement> INLINE_CLASS_WITH_INITIALIZER = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<KtProperty> PROPERTY_WITH_BACKING_FIELD_INSIDE_INLINE_CLASS = DiagnosticFactory0.create(ERROR, DECLARATION_SIGNATURE);
+    DiagnosticFactory0<PsiElement> DELEGATED_PROPERTY_INSIDE_INLINE_CLASS = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory1<KtTypeReference, KotlinType> INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE = DiagnosticFactory1.create(ERROR);
+    DiagnosticFactory0<PsiElement> INLINE_CLASS_CANNOT_IMPLEMENT_INTERFACE_BY_DELEGATION = DiagnosticFactory0.create(ERROR);
 
     // Secondary constructors
 

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

@@ -651,7 +651,9 @@ public class DefaultErrorMessages {
         MAP.put(INLINE_CLASS_CONSTRUCTOR_NOT_FINAL_READ_ONLY_PARAMETER, "Inline class primary constructor must have only final read-only (val) property parameter");
         MAP.put(INLINE_CLASS_WITH_INITIALIZER, "Inline class cannot have an initializer block");
         MAP.put(PROPERTY_WITH_BACKING_FIELD_INSIDE_INLINE_CLASS, "Inline class cannot have properties with backing fields");
+        MAP.put(DELEGATED_PROPERTY_INSIDE_INLINE_CLASS, "Inline class cannot have delegated properties");
         MAP.put(INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE, "Inline class cannot have value parameter of type ''{0}''", RENDER_TYPE);
+        MAP.put(INLINE_CLASS_CANNOT_IMPLEMENT_INTERFACE_BY_DELEGATION, "Inline class cannot implement an interface by delegation");
 
         MAP.put(VARIANCE_ON_TYPE_PARAMETER_NOT_ALLOWED, "Variance annotations are only allowed for type parameters of classes and interfaces");
         MAP.put(BOUND_ON_TYPE_ALIAS_PARAMETER_NOT_ALLOWED, "Bounds are not allowed on type alias parameters");

compiler/frontend/src/org/jetbrains/kotlin/resolve/checkers/InlineClassDeclarationChecker.kt

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.resolve.checkers
 
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.diagnostics.Errors
 import org.jetbrains.kotlin.lexer.KtTokens
@@ -15,6 +16,7 @@ import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.isInlineClass
 import org.jetbrains.kotlin.resolve.substitutedUnderlyingType
+import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.typeUtil.isNothing
 import org.jetbrains.kotlin.types.typeUtil.isTypeParameter
 import org.jetbrains.kotlin.types.typeUtil.isUnit
@@ -78,15 +80,32 @@ object InlineClassDeclarationChecker : DeclarationChecker {
         }
 
         val baseParameterType = descriptor.safeAs<ClassDescriptor>()?.defaultType?.substitutedUnderlyingType()
-        if (baseParameterType != null &&
-            (baseParameterType.isUnit() || baseParameterType.isNothing() || baseParameterType.isTypeParameter())
-        ) {
+        if (baseParameterType != null && baseParameterType.isInapplicableParameterType()) {
             val typeReference = baseParameter.typeReference
             if (typeReference != null) {
                 trace.report(Errors.INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE.on(typeReference, baseParameterType))
                 return
             }
         }
+
+        for (supertypeEntry in declaration.superTypeListEntries) {
+            if (supertypeEntry is KtDelegatedSuperTypeEntry) {
+                trace.report(Errors.INLINE_CLASS_CANNOT_IMPLEMENT_INTERFACE_BY_DELEGATION.on(supertypeEntry))
+                return
+            }
+        }
+    }
+
+    private fun KotlinType.isInapplicableParameterType() =
+        isUnit() || isNothing() || isTypeParameter() || isGenericArrayOfTypeParameter()
+
+    private fun KotlinType.isGenericArrayOfTypeParameter(): Boolean {
+        if (!KotlinBuiltIns.isArray(this)) return false
+        val argument0 = arguments[0]
+        if (argument0.isStarProjection) return false
+        val argument0type = argument0.type
+        return argument0type.isTypeParameter() ||
+                argument0type.isGenericArrayOfTypeParameter()
     }
 
     private fun isParameterAcceptableForInlineClass(parameter: KtParameter): Boolean {
@@ -105,5 +124,9 @@ class PropertiesWithBackingFieldsInsideInlineClass : DeclarationChecker {
         if (context.trace.get(BindingContext.BACKING_FIELD_REQUIRED, descriptor) == true) {
             context.trace.report(Errors.PROPERTY_WITH_BACKING_FIELD_INSIDE_INLINE_CLASS.on(declaration))
         }
+
+        declaration.delegate?.let {
+            context.trace.report(Errors.DELEGATED_PROPERTY_INSIDE_INLINE_CLASS.on(it))
+        }
     }
 }

compiler/testData/diagnostics/tests/inlineClasses/delegatedPropertyInInlineClass.kt

@@ -0,0 +1,28 @@
+// !LANGUAGE: +InlineClasses
+
+class Val {
+    operator fun getValue(thisRef: Any?, kProp: Any?) = 1
+}
+
+class Var {
+    operator fun getValue(thisRef: Any?, kProp: Any?) = 2
+    operator fun setValue(thisRef: Any?, kProp: Any?, value: Int) {}
+}
+
+
+object ValObject {
+    operator fun getValue(thisRef: Any?, kProp: Any?) = 1
+}
+
+object VarObject {
+    operator fun getValue(thisRef: Any?, kProp: Any?) = 2
+    operator fun setValue(thisRef: Any?, kProp: Any?, value: Int) {}
+}
+
+inline class Z(val data: Int) {
+    val testVal <!DELEGATED_PROPERTY_INSIDE_INLINE_CLASS!>by Val()<!>
+    var testVar <!DELEGATED_PROPERTY_INSIDE_INLINE_CLASS!>by Var()<!>
+
+    val testValBySingleton <!DELEGATED_PROPERTY_INSIDE_INLINE_CLASS!>by ValObject<!>
+    var testVarBySingleton <!DELEGATED_PROPERTY_INSIDE_INLINE_CLASS!>by VarObject<!>
+}

compiler/testData/diagnostics/tests/inlineClasses/delegatedPropertyInInlineClass.txt

@@ -0,0 +1,47 @@
+package
+
+public final class Val {
+    public constructor Val()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kProp: kotlin.Any?): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public object ValObject {
+    private constructor ValObject()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kProp: kotlin.Any?): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Var {
+    public constructor Var()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kProp: kotlin.Any?): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final operator fun setValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kProp: kotlin.Any?, /*2*/ value: kotlin.Int): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public object VarObject {
+    private constructor VarObject()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kProp: kotlin.Any?): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final operator fun setValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kProp: kotlin.Any?, /*2*/ value: kotlin.Int): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final inline class Z {
+    public constructor Z(/*0*/ data: kotlin.Int)
+    public final val data: kotlin.Int
+    public final val testVal: kotlin.Int
+    public final val testValBySingleton: kotlin.Int
+    public final var testVar: kotlin.Int
+    public final var testVarBySingleton: kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/inlineClasses/inlineClassCannotImplementInterfaceByDelegation.kt

@@ -0,0 +1,9 @@
+// !LANGUAGE: +InlineClasses
+
+interface IFoo
+
+object FooImpl : IFoo
+
+inline class Test1(val x: Any) : <!INLINE_CLASS_CANNOT_IMPLEMENT_INTERFACE_BY_DELEGATION!>IFoo by FooImpl<!>
+
+inline class Test2(val x: IFoo) : <!INLINE_CLASS_CANNOT_IMPLEMENT_INTERFACE_BY_DELEGATION!>IFoo by x<!>

compiler/testData/diagnostics/tests/inlineClasses/inlineClassCannotImplementInterfaceByDelegation.txt

@@ -0,0 +1,30 @@
+package
+
+public object FooImpl : IFoo {
+    private constructor FooImpl()
+    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 interface IFoo {
+    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 inline class Test1 : IFoo {
+    public constructor Test1(/*0*/ x: kotlin.Any)
+    public final val x: kotlin.Any
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}
+
+public final inline class Test2 : IFoo {
+    public constructor Test2(/*0*/ x: IFoo)
+    public final val x: IFoo
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/inlineClasses/inlineClassWithForbiddenUnderlyingType.kt

@@ -3,6 +3,12 @@
 inline class Foo<T>(val x: <!INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE!>T<!>)
 inline class FooNullable<T>(val x: <!INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE!>T?<!>)
 
+inline class FooGenericArray<T>(val x: <!INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE!>Array<T><!>)
+inline class FooGenericArray2<T>(val x: <!INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE!>Array<Array<T>><!>)
+
+inline class FooStarProjectedArray(val x: Array<*>)
+inline class FooStarProjectedArray2(val x: Array<Array<*>>)
+
 inline class Bar(val u: <!INLINE_CLASS_HAS_INAPPLICABLE_PARAMETER_TYPE!>Unit<!>)
 inline class BarNullable(val u: Unit?)
 

compiler/testData/diagnostics/tests/inlineClasses/inlineClassWithForbiddenUnderlyingType.txt

@@ -40,6 +40,22 @@ public final inline class Foo</*0*/ T> {
     public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
 }
 
+public final inline class FooGenericArray</*0*/ T> {
+    public constructor FooGenericArray</*0*/ T>(/*0*/ x: kotlin.Array<T>)
+    public final val x: kotlin.Array<T>
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}
+
+public final inline class FooGenericArray2</*0*/ T> {
+    public constructor FooGenericArray2</*0*/ T>(/*0*/ x: kotlin.Array<kotlin.Array<T>>)
+    public final val x: kotlin.Array<kotlin.Array<T>>
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}
+
 public final inline class FooNullable</*0*/ T> {
     public constructor FooNullable</*0*/ T>(/*0*/ x: T?)
     public final val x: T?
@@ -47,3 +63,19 @@ public final inline class FooNullable</*0*/ T> {
     public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
     public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
 }
+
+public final inline class FooStarProjectedArray {
+    public constructor FooStarProjectedArray(/*0*/ x: kotlin.Array<*>)
+    public final val x: kotlin.Array<*>
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}
+
+public final inline class FooStarProjectedArray2 {
+    public constructor FooStarProjectedArray2(/*0*/ x: kotlin.Array<kotlin.Array<*>>)
+    public final val x: kotlin.Array<kotlin.Array<*>>
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}

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

@@ -10857,11 +10857,21 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 runTest("compiler/testData/diagnostics/tests/inlineClasses/basicInlineClassDeclarationDisabled.kt");
             }
 
+            @TestMetadata("delegatedPropertyInInlineClass.kt")
+            public void testDelegatedPropertyInInlineClass() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inlineClasses/delegatedPropertyInInlineClass.kt");
+            }
+
             @TestMetadata("identityComparisonWithInlineClasses.kt")
             public void testIdentityComparisonWithInlineClasses() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/inlineClasses/identityComparisonWithInlineClasses.kt");
             }
 
+            @TestMetadata("inlineClassCannotImplementInterfaceByDelegation.kt")
+            public void testInlineClassCannotImplementInterfaceByDelegation() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inlineClasses/inlineClassCannotImplementInterfaceByDelegation.kt");
+            }
+
             @TestMetadata("inlineClassDeclarationCheck.kt")
             public void testInlineClassDeclarationCheck() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/inlineClasses/inlineClassDeclarationCheck.kt");

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

@@ -10857,11 +10857,21 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                 runTest("compiler/testData/diagnostics/tests/inlineClasses/basicInlineClassDeclarationDisabled.kt");
             }
 
+            @TestMetadata("delegatedPropertyInInlineClass.kt")
+            public void testDelegatedPropertyInInlineClass() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inlineClasses/delegatedPropertyInInlineClass.kt");
+            }
+
             @TestMetadata("identityComparisonWithInlineClasses.kt")
             public void testIdentityComparisonWithInlineClasses() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/inlineClasses/identityComparisonWithInlineClasses.kt");
             }
 
+            @TestMetadata("inlineClassCannotImplementInterfaceByDelegation.kt")
+            public void testInlineClassCannotImplementInterfaceByDelegation() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/inlineClasses/inlineClassCannotImplementInterfaceByDelegation.kt");
+            }
+
             @TestMetadata("inlineClassDeclarationCheck.kt")
             public void testInlineClassDeclarationCheck() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/inlineClasses/inlineClassDeclarationCheck.kt");