diff --git a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizeAnnotationChecker.kt b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizeAnnotationChecker.kt
index becdf89393d..db8eff03468 100644
--- a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizeAnnotationChecker.kt
+++ b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizeAnnotationChecker.kt
@@ -5,16 +5,24 @@
 
 package org.jetbrains.kotlin.parcelize.fir.diagnostics
 
+import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.diagnostics.DiagnosticReporter
 import org.jetbrains.kotlin.diagnostics.reportOn
 import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
 import org.jetbrains.kotlin.fir.analysis.checkers.expression.FirAnnotationCallChecker
+import org.jetbrains.kotlin.fir.analysis.checkers.findClosestClassOrObject
+import org.jetbrains.kotlin.fir.correspondingProperty
+import org.jetbrains.kotlin.fir.declarations.FirValueParameter
+import org.jetbrains.kotlin.fir.declarations.utils.fromPrimaryConstructor
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
+import org.jetbrains.kotlin.fir.expressions.classId
 import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
 import org.jetbrains.kotlin.fir.resolve.toFirRegularClassSymbol
-import org.jetbrains.kotlin.fir.types.ConeClassLikeType
-import org.jetbrains.kotlin.fir.types.coneType
+import org.jetbrains.kotlin.fir.symbols.impl.ConeClassLikeLookupTagImpl
+import org.jetbrains.kotlin.fir.types.*
+import org.jetbrains.kotlin.fir.types.impl.ConeClassLikeTypeImpl
 import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.parcelize.ParcelizeNames
 import org.jetbrains.kotlin.parcelize.ParcelizeNames.DEPRECATED_RUNTIME_PACKAGE
 import org.jetbrains.kotlin.parcelize.ParcelizeNames.IGNORED_ON_PARCEL_CLASS_IDS
 import org.jetbrains.kotlin.parcelize.ParcelizeNames.PARCELIZE_CLASS_CLASS_IDS
@@ -28,12 +36,14 @@ object FirParcelizeAnnotationChecker : FirAnnotationCallChecker() {
         val resolvedAnnotationSymbol = annotationType.lookupTag.toFirRegularClassSymbol(context.session) ?: return
         when (val annotationClassId = resolvedAnnotationSymbol.classId) {
             in TYPE_PARCELER_CLASS_IDS -> {
-                checkTypeParcelerUsage(expression, context, reporter)
-                checkDeprecatedAnnotations(expression, annotationClassId, context, reporter, isForbidden = true)
+                if (checkDeprecatedAnnotations(expression, annotationClassId, context, reporter, isForbidden = true)) {
+                    checkTypeParcelerUsage(expression, context, reporter)
+                }
             }
             in WRITE_WITH_CLASS_IDS -> {
-                checkWriteWithUsage(expression, context, reporter)
-                checkDeprecatedAnnotations(expression, annotationClassId, context, reporter, isForbidden = true)
+                if (checkDeprecatedAnnotations(expression, annotationClassId, context, reporter, isForbidden = true)) {
+                    checkWriteWithUsage(expression, context, reporter)
+                }
             }
             in IGNORED_ON_PARCEL_CLASS_IDS -> {
                 checkDeprecatedAnnotations(expression, annotationClassId, context, reporter, isForbidden = false)
@@ -50,20 +60,83 @@ object FirParcelizeAnnotationChecker : FirAnnotationCallChecker() {
         context: CheckerContext,
         reporter: DiagnosticReporter,
         isForbidden: Boolean
-    ) {
+    ): Boolean {
         if (annotationClassId.packageFqName == DEPRECATED_RUNTIME_PACKAGE) {
             val factory = if (isForbidden) KtErrorsParcelize.FORBIDDEN_DEPRECATED_ANNOTATION else KtErrorsParcelize.DEPRECATED_ANNOTATION
             reporter.reportOn(annotationCall.source, factory, context)
+            return false
+        }
+        return true
+    }
+
+    private fun checkTypeParcelerUsage(annotationCall: FirAnnotationCall, context: CheckerContext, reporter: DiagnosticReporter) {
+        val thisMappedType = annotationCall.typeArguments.takeIf { it.size == 2 }?.first()?.toConeTypeProjection()?.type
+            ?: return
+
+        val annotationContainer = context.annotationContainers.lastOrNull()
+        val duplicatingAnnotationCount = annotationContainer
+            ?.annotations
+            ?.filter { it.classId in TYPE_PARCELER_CLASS_IDS }
+            ?.mapNotNull { it.typeArguments.takeIf { it.size == 2 }?.first()?.toConeTypeProjection()?.type }
+            ?.count { it == thisMappedType }
+
+        if (duplicatingAnnotationCount != null && duplicatingAnnotationCount > 1) {
+            val reportElement = annotationCall.typeArguments.firstOrNull()?.source ?: annotationCall.source
+            reporter.reportOn(reportElement, KtErrorsParcelize.DUPLICATING_TYPE_PARCELERS, context)
+            return
+        }
+
+        checkIfTheContainingClassIsParcelize(annotationCall, context, reporter)
+
+        // If we are looking at a parameter of the primary constructor of a class, check that the
+        // enclosing class doesn't have the same TypeParceler annotation.
+        if (annotationContainer is FirValueParameter && annotationContainer.correspondingProperty?.fromPrimaryConstructor == true) {
+            val enclosingClass = context.findClosestClassOrObject() ?: return
+
+            val annotationType = annotationCall.typeRef.coneType
+            if (enclosingClass.annotations.any { it.typeRef.coneType == annotationType }) {
+                val reportElement = annotationCall.calleeReference.source ?: annotationCall.source
+                reporter.reportOn(reportElement, KtErrorsParcelize.REDUNDANT_TYPE_PARCELER, enclosingClass.symbol, context)
+            }
         }
     }
 
-    @Suppress("UNUSED_PARAMETER")
-    private fun checkTypeParcelerUsage(annotationCall: FirAnnotationCall, context: CheckerContext, reporter: DiagnosticReporter) {
-        // TODO: this check checks type arguments of annotation which are not supported in FIR
+    private fun checkWriteWithUsage(annotationCall: FirAnnotationCall, context: CheckerContext, reporter: DiagnosticReporter) {
+        checkIfTheContainingClassIsParcelize(annotationCall, context, reporter)
+
+        // For `@WriteWith<P>` check that `P` is an object.
+        val parcelerType = annotationCall.typeArguments.singleOrNull()?.toConeTypeProjection()?.type ?: return
+        if (parcelerType.toRegularClassSymbol(context.session)?.classKind != ClassKind.OBJECT) {
+            val reportElement = annotationCall.typeArguments.singleOrNull()?.source ?: annotationCall.source
+            reporter.reportOn(reportElement, KtErrorsParcelize.PARCELER_SHOULD_BE_OBJECT, context)
+        }
+
+        // For `@WriteWith<P> T` check that `P` is a subtype of `Parceler<T>`.
+        //
+        // From the perspective of the `WriteWith` annotation call, `T` corresponds to the nearest enclosing annotation container
+        // stripped of annotations.
+        //
+        // It's safe to assume that `Parceler` refers to `kotlinx.parcelize.Parceler` rather than `kotlinx.android.parcel.Parceler`,
+        // since using the deprecated `WriteWith` annotation is an error.
+        val targetType = (context.annotationContainers.lastOrNull() as? FirTypeRef)?.coneType?.withAttributes(ConeAttributes.Empty)
+            ?: return
+        val expectedType = ConeClassLikeTypeImpl(
+            ConeClassLikeLookupTagImpl(ParcelizeNames.PARCELER_ID),
+            arrayOf(targetType),
+            isNullable = false
+        )
+        if (!parcelerType.isSubtypeOf(expectedType, context.session)) {
+            val reportElement = annotationCall.typeArguments.singleOrNull()?.source ?: annotationCall.source
+            reporter.reportOn(reportElement, KtErrorsParcelize.PARCELER_TYPE_INCOMPATIBLE, parcelerType, targetType, context)
+        }
     }
 
-    @Suppress("UNUSED_PARAMETER")
-    private fun checkWriteWithUsage(annotationCall: FirAnnotationCall, context: CheckerContext, reporter: DiagnosticReporter) {
-        // TODO: this check checks type arguments of annotation which are not supported in FIR
+    private fun checkIfTheContainingClassIsParcelize(annotationCall: FirAnnotationCall, context: CheckerContext, reporter: DiagnosticReporter) {
+        val enclosingClass = context.findClosestClassOrObject() ?: return
+
+        if (!enclosingClass.symbol.isParcelize(context.session)) {
+            val reportElement = annotationCall.calleeReference.source ?: annotationCall.source
+            reporter.reportOn(reportElement, KtErrorsParcelize.CLASS_SHOULD_BE_PARCELIZE, enclosingClass.symbol, context)
+        }
     }
 }
diff --git a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizePropertyChecker.kt b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizePropertyChecker.kt
index ebffc4fdf7d..30af1fb50f9 100644
--- a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizePropertyChecker.kt
+++ b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/FirParcelizePropertyChecker.kt
@@ -5,7 +5,9 @@
 
 package org.jetbrains.kotlin.parcelize.fir.diagnostics
 
+import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.annotations.AnnotationUseSiteTarget
+import org.jetbrains.kotlin.descriptors.isEnumClass
 import org.jetbrains.kotlin.diagnostics.DiagnosticReporter
 import org.jetbrains.kotlin.diagnostics.reportOn
 import org.jetbrains.kotlin.fir.FirSession
@@ -18,12 +20,13 @@ import org.jetbrains.kotlin.fir.declarations.utils.fromPrimaryConstructor
 import org.jetbrains.kotlin.fir.declarations.utils.hasBackingField
 import org.jetbrains.kotlin.fir.declarations.utils.isCompanion
 import org.jetbrains.kotlin.fir.expressions.FirAnnotation
+import org.jetbrains.kotlin.fir.resolve.fqName
+import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
 import org.jetbrains.kotlin.fir.resolve.lookupSuperTypes
 import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
-import org.jetbrains.kotlin.fir.types.ConeErrorType
-import org.jetbrains.kotlin.fir.types.classId
-import org.jetbrains.kotlin.fir.types.coneType
-import org.jetbrains.kotlin.fir.types.toRegularClassSymbol
+import org.jetbrains.kotlin.fir.types.*
+import org.jetbrains.kotlin.parcelize.BuiltinParcelableTypes
+import org.jetbrains.kotlin.parcelize.ParcelizeNames
 import org.jetbrains.kotlin.parcelize.ParcelizeNames.CREATOR_NAME
 import org.jetbrains.kotlin.parcelize.ParcelizeNames.IGNORED_ON_PARCEL_CLASS_IDS
 import org.jetbrains.kotlin.parcelize.ParcelizeNames.PARCELER_ID
@@ -55,7 +58,6 @@ object FirParcelizePropertyChecker : FirPropertyChecker() {
         }
     }
 
-    @Suppress("UNUSED_PARAMETER")
     private fun checkParcelableClassProperty(
         property: FirProperty,
         containingClassSymbol: FirRegularClassSymbol,
@@ -63,18 +65,92 @@ object FirParcelizePropertyChecker : FirPropertyChecker() {
         reporter: DiagnosticReporter
     ) {
         val type = property.returnTypeRef.coneType
-        if (type is ConeErrorType || containingClassSymbol.hasCustomParceler(context.session)) return
-        /*
-         * TODO: abstract code from ParcelSerializer or IrParcelSerializerFactory to avoid duplication
-         *    of allowed types checking
-         */
+        if (type is ConeErrorType || containingClassSymbol.hasCustomParceler(context.session) || property.hasIgnoredOnParcel()) {
+            return
+        }
+
+        val session = context.session
+        val customParcelerTypes = getCustomParcelerTypes(property.annotations + containingClassSymbol.annotations, session)
+        if (!checkParcelableType(type, customParcelerTypes, session)) {
+            reporter.reportOn(property.returnTypeRef.source, KtErrorsParcelize.PARCELABLE_TYPE_NOT_SUPPORTED, context)
+        }
+    }
+
+    private fun getCustomParcelerTypes(annotations: List<FirAnnotation>, session: FirSession): Set<ConeKotlinType> =
+        annotations.mapNotNullTo(mutableSetOf()) { annotation ->
+            if (annotation.fqName(session) in ParcelizeNames.TYPE_PARCELER_FQ_NAMES && annotation.typeArguments.size == 2) {
+                annotation.typeArguments[0].toConeTypeProjection().type
+            } else {
+                null
+            }
+        }
+
+    private fun checkParcelableType(type: ConeKotlinType, customParcelerTypes: Set<ConeKotlinType>, session: FirSession): Boolean {
+        if (type.hasParcelerAnnotation(session) || type in customParcelerTypes) {
+            return true
+        }
+
+        val upperBound = type.getErasedUpperBound(session)
+        val symbol = upperBound?.toRegularClassSymbol(session)
+            ?: return false
+
+        if (symbol.classKind.isSingleton || symbol.classKind.isEnumClass) {
+            return true
+        }
+
+        val fqName = symbol.classId.asFqNameString()
+        if (fqName in BuiltinParcelableTypes.PARCELABLE_BASE_TYPE_FQNAMES) {
+            return true
+        }
+
+        if (fqName in BuiltinParcelableTypes.PARCELABLE_CONTAINER_FQNAMES) {
+            return upperBound.typeArguments.all { projection ->
+                projection.type?.let { checkParcelableType(it, customParcelerTypes, session) } ?: false
+            }
+        }
+
+        return with(session.typeContext) {
+            type.anySuperTypeConstructor {
+                it is ConeKotlinType &&
+                        (it.classId?.asFqNameString() in BuiltinParcelableTypes.PARCELABLE_SUPERTYPE_FQNAMES ||
+                                it.isBuiltinFunctionalType(session))
+            }
+        }
+    }
+
+    private fun ConeKotlinType.getErasedUpperBound(session: FirSession): ConeClassLikeType? =
+        when (this) {
+            is ConeClassLikeType ->
+                fullyExpandedType(session)
+
+            is ConeTypeParameterType -> {
+                val bounds = lookupTag.typeParameterSymbol.resolvedBounds
+                val representativeBound = bounds.firstOrNull {
+                    val kind = it.coneType.toRegularClassSymbol(session)?.classKind
+                        ?: return@firstOrNull false
+                    kind != ClassKind.INTERFACE && kind != ClassKind.ANNOTATION_CLASS
+                } ?: bounds.first()
+                representativeBound.coneType.getErasedUpperBound(session)
+            }
+
+            else ->
+                null
+        }
+
+    private fun ConeKotlinType.hasParcelerAnnotation(session: FirSession): Boolean {
+        for (annotation in customAnnotations) {
+            val fqName = annotation.fqName(session)
+            if (fqName in ParcelizeNames.RAW_VALUE_ANNOTATION_FQ_NAMES || fqName in ParcelizeNames.WRITE_WITH_FQ_NAMES) {
+                return true
+            }
+        }
+        return false
     }
 
     private fun FirProperty.hasIgnoredOnParcel(): Boolean {
         return annotations.hasIgnoredOnParcel() || (getter?.annotations?.hasIgnoredOnParcel() ?: false)
     }
 
-
     private fun List<FirAnnotation>.hasIgnoredOnParcel(): Boolean {
         return this.any {
             if (it.annotationTypeRef.coneType.classId !in IGNORED_ON_PARCEL_CLASS_IDS) return@any false
diff --git a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtDefaultErrorMessagesParcelize.kt b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtDefaultErrorMessagesParcelize.kt
index 1cbdb321eb5..4fe91029615 100644
--- a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtDefaultErrorMessagesParcelize.kt
+++ b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtDefaultErrorMessagesParcelize.kt
@@ -19,8 +19,8 @@ package org.jetbrains.kotlin.parcelize.fir.diagnostics
 import org.jetbrains.kotlin.diagnostics.KtDiagnostic
 import org.jetbrains.kotlin.diagnostics.KtDiagnosticFactoryToRendererMap
 import org.jetbrains.kotlin.diagnostics.KtDiagnosticRenderer
-import org.jetbrains.kotlin.diagnostics.rendering.Renderers.RENDER_CLASS_OR_OBJECT
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirDiagnosticRenderers.RENDER_TYPE
+import org.jetbrains.kotlin.fir.analysis.diagnostics.FirDiagnosticRenderers.RENDER_CLASS_OR_OBJECT
 import org.jetbrains.kotlin.parcelize.fir.diagnostics.KtErrorsParcelize.CLASS_SHOULD_BE_PARCELIZE
 import org.jetbrains.kotlin.parcelize.fir.diagnostics.KtErrorsParcelize.CREATOR_DEFINITION_IS_NOT_ALLOWED
 import org.jetbrains.kotlin.parcelize.fir.diagnostics.KtErrorsParcelize.DEPRECATED_ANNOTATION
diff --git a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtErrorsParcelize.kt b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtErrorsParcelize.kt
index 25ba24eb0d2..e3b875c9960 100644
--- a/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtErrorsParcelize.kt
+++ b/plugins/parcelize/parcelize-compiler/parcelize.k2/src/org/jetbrains/kotlin/parcelize/fir/diagnostics/KtErrorsParcelize.kt
@@ -22,6 +22,8 @@ import org.jetbrains.kotlin.diagnostics.SourceElementPositioningStrategies.DELEG
 import org.jetbrains.kotlin.diagnostics.SourceElementPositioningStrategies.INNER_MODIFIER
 import org.jetbrains.kotlin.diagnostics.SourceElementPositioningStrategies.NAME_IDENTIFIER
 import org.jetbrains.kotlin.diagnostics.SourceElementPositioningStrategies.OVERRIDE_MODIFIER
+import org.jetbrains.kotlin.fir.symbols.impl.FirClassSymbol
+import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
 import org.jetbrains.kotlin.fir.types.ConeKotlinType
 import org.jetbrains.kotlin.psi.KtClassOrObject
 
@@ -43,8 +45,8 @@ object KtErrorsParcelize {
     val PARCELER_SHOULD_BE_OBJECT by error0<PsiElement>()
     val PARCELER_TYPE_INCOMPATIBLE by error2<PsiElement, ConeKotlinType, ConeKotlinType>()
     val DUPLICATING_TYPE_PARCELERS by error0<PsiElement>()
-    val REDUNDANT_TYPE_PARCELER by warning1<PsiElement, KtClassOrObject>()
-    val CLASS_SHOULD_BE_PARCELIZE by error1<PsiElement, KtClassOrObject>()
+    val REDUNDANT_TYPE_PARCELER by warning1<PsiElement, FirClassSymbol<*>>()
+    val CLASS_SHOULD_BE_PARCELIZE by error1<PsiElement, FirClassSymbol<*>>()
     val FORBIDDEN_DEPRECATED_ANNOTATION by error0<PsiElement>()
     val DEPRECATED_ANNOTATION by warning0<PsiElement>()
     val DEPRECATED_PARCELER by error0<PsiElement>()
diff --git a/plugins/parcelize/parcelize-compiler/testData/diagnostics/customParcelers.fir.kt b/plugins/parcelize/parcelize-compiler/testData/diagnostics/customParcelers.fir.kt
index 0e856f4efa3..bca096f35d5 100644
--- a/plugins/parcelize/parcelize-compiler/testData/diagnostics/customParcelers.fir.kt
+++ b/plugins/parcelize/parcelize-compiler/testData/diagnostics/customParcelers.fir.kt
@@ -19,27 +19,27 @@ class StringClassParceler : Parceler<String> {
     override fun String.write(parcel: Parcel, flags: Int) = TODO()
 }
 
-@TypeParceler<String, StringParceler>
-class MissingParcelizeAnnotation(val a: @WriteWith<StringParceler> String)
+@<!CLASS_SHOULD_BE_PARCELIZE!>TypeParceler<!><String, StringParceler>
+class MissingParcelizeAnnotation(val a: @<!CLASS_SHOULD_BE_PARCELIZE!>WriteWith<!><StringParceler> String)
 
 @Parcelize
 @TypeParceler<String, StringClassParceler>
-class ShouldBeClass(val a: @WriteWith<StringClassParceler> String) : Parcelable
+class ShouldBeClass(val a: @WriteWith<<!PARCELER_SHOULD_BE_OBJECT!>StringClassParceler<!>> String) : Parcelable
 
 @Parcelize
 class Test(
-    val a: @WriteWith<StringParceler> Int,
+    val a: @WriteWith<<!PARCELER_TYPE_INCOMPATIBLE!>StringParceler<!>> Int,
     val b: @WriteWith<StringParceler> String,
-    val c: @WriteWith<StringParceler> CharSequence,
-    val d: @WriteWith<CharSequenceParceler> String,
+    val c: @WriteWith<<!PARCELER_TYPE_INCOMPATIBLE!>StringParceler<!>> CharSequence,
+    val d: @WriteWith<<!PARCELER_TYPE_INCOMPATIBLE!>CharSequenceParceler<!>> String,
     val e: @WriteWith<CharSequenceParceler> CharSequence
 ) : Parcelable
 
 @Parcelize
 @TypeParceler<String, StringParceler>
-class Test2(@TypeParceler<String, StringParceler> val a: String) : Parcelable
+class Test2(@<!REDUNDANT_TYPE_PARCELER!>TypeParceler<!><String, StringParceler> val a: String) : Parcelable
 
 @Parcelize
-@TypeParceler<String, StringParceler>
-@TypeParceler<String, CharSequenceParceler>
+@TypeParceler<<!DUPLICATING_TYPE_PARCELERS!>String<!>, StringParceler>
+@TypeParceler<<!DUPLICATING_TYPE_PARCELERS!>String<!>, CharSequenceParceler>
 class Test3(val a: String) : Parcelable
diff --git a/plugins/parcelize/parcelize-compiler/testData/diagnostics/kt20062.fir.kt b/plugins/parcelize/parcelize-compiler/testData/diagnostics/kt20062.fir.kt
deleted file mode 100644
index 939b87f978b..00000000000
--- a/plugins/parcelize/parcelize-compiler/testData/diagnostics/kt20062.fir.kt
+++ /dev/null
@@ -1,20 +0,0 @@
-package test
-
-import kotlinx.parcelize.*
-import android.os.*
-
-class Box(val value: String)
-
-@Parcelize
-class Foo(val box: Box): Parcelable {
-    companion object : Parceler<Foo> {
-        override fun create(parcel: Parcel) = Foo(Box(parcel.readString()))
-
-        override fun Foo.write(parcel: Parcel, flags: Int) {
-            parcel.writeString(box.value)
-        }
-    }
-}
-
-@Parcelize
-class Foo2(val box: Box): Parcelable
diff --git a/plugins/parcelize/parcelize-compiler/testData/diagnostics/kt20062.kt b/plugins/parcelize/parcelize-compiler/testData/diagnostics/kt20062.kt
index 36f692501ed..198d8cba6e4 100644
--- a/plugins/parcelize/parcelize-compiler/testData/diagnostics/kt20062.kt
+++ b/plugins/parcelize/parcelize-compiler/testData/diagnostics/kt20062.kt
@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 package test
 
 import kotlinx.parcelize.*
diff --git a/plugins/parcelize/parcelize-compiler/testData/diagnostics/unsupportedType.fir.kt b/plugins/parcelize/parcelize-compiler/testData/diagnostics/unsupportedType.fir.kt
deleted file mode 100644
index e1d1b2cc392..00000000000
--- a/plugins/parcelize/parcelize-compiler/testData/diagnostics/unsupportedType.fir.kt
+++ /dev/null
@@ -1,17 +0,0 @@
-package test
-
-import kotlinx.parcelize.Parcelize
-import kotlinx.parcelize.RawValue
-import android.os.Parcelable
-
-@Parcelize
-class User(
-        val a: String,
-        val b: Any,
-        val c: Any?,
-        val d: Map<Any, String>,
-        val e: @RawValue Any?,
-        val f: @RawValue Map<String, Any>,
-        val g: Map<String, @RawValue Any>,
-        val h: Map<@RawValue Any, List<@RawValue Any>>
-) : Parcelable
diff --git a/plugins/parcelize/parcelize-compiler/testData/diagnostics/unsupportedType.kt b/plugins/parcelize/parcelize-compiler/testData/diagnostics/unsupportedType.kt
index 74956c162a1..56b5288b25a 100644
--- a/plugins/parcelize/parcelize-compiler/testData/diagnostics/unsupportedType.kt
+++ b/plugins/parcelize/parcelize-compiler/testData/diagnostics/unsupportedType.kt
@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 package test
 
 import kotlinx.parcelize.Parcelize