FIR: check subclass of sealed class

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDataClassConverters.kt

@@ -450,6 +450,26 @@ internal val KT_DIAGNOSTIC_CONVERTER = KtDiagnosticConverterBuilder.buildConvert
             token,
         )
     }
+    add(FirErrors.SEALED_INHERITOR_IN_DIFFERENT_PACKAGE) { firDiagnostic ->
+        SealedInheritorInDifferentPackageImpl(
+            firDiagnostic.a,
+            firDiagnostic.b,
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
+    add(FirErrors.SEALED_INHERITOR_IN_DIFFERENT_MODULE) { firDiagnostic ->
+        SealedInheritorInDifferentModuleImpl(
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
+    add(FirErrors.CLASS_INHERITS_JAVA_SEALED_CLASS) { firDiagnostic ->
+        ClassInheritsJavaSealedClassImpl(
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
     add(FirErrors.SUPERTYPE_NOT_A_CLASS_OR_INTERFACE) { firDiagnostic ->
         SupertypeNotAClassOrInterfaceImpl(
             firDiagnostic.a,

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDiagnostics.kt

@@ -341,6 +341,20 @@ sealed class KtFirDiagnostic<PSI : PsiElement> : KtDiagnosticWithPsi<PSI> {
         override val diagnosticClass get() = SealedSupertypeInLocalClass::class
     }
 
+    abstract class SealedInheritorInDifferentPackage : KtFirDiagnostic<KtTypeReference>() {
+        override val diagnosticClass get() = SealedInheritorInDifferentPackage::class
+        abstract val subclassPackage: FqName
+        abstract val basePackage: FqName
+    }
+
+    abstract class SealedInheritorInDifferentModule : KtFirDiagnostic<KtTypeReference>() {
+        override val diagnosticClass get() = SealedInheritorInDifferentModule::class
+    }
+
+    abstract class ClassInheritsJavaSealedClass : KtFirDiagnostic<KtTypeReference>() {
+        override val diagnosticClass get() = ClassInheritsJavaSealedClass::class
+    }
+
     abstract class SupertypeNotAClassOrInterface : KtFirDiagnostic<KtElement>() {
         override val diagnosticClass get() = SupertypeNotAClassOrInterface::class
         abstract val reason: String

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/diagnostics/KtFirDiagnosticsImpl.kt

@@ -522,6 +522,29 @@ internal class SealedSupertypeInLocalClassImpl(
     override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
 }
 
+internal class SealedInheritorInDifferentPackageImpl(
+    override val subclassPackage: FqName,
+    override val basePackage: FqName,
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.SealedInheritorInDifferentPackage(), KtAbstractFirDiagnostic<KtTypeReference> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
+internal class SealedInheritorInDifferentModuleImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.SealedInheritorInDifferentModule(), KtAbstractFirDiagnostic<KtTypeReference> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
+internal class ClassInheritsJavaSealedClassImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.ClassInheritsJavaSealedClass(), KtAbstractFirDiagnostic<KtTypeReference> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
 internal class SupertypeNotAClassOrInterfaceImpl(
     override val reason: String,
     firDiagnostic: FirPsiDiagnostic,