Konsist: check if sealed class could be sealed interface and fix existing issues.

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/ExpandableBottomSheetScaffold.kt

@@ -170,9 +170,8 @@ private fun CustomSheetState.getIntOffset(): Int? = try {
     null
 }
 
-private sealed class Slot {
-    data class SheetContent(val key: Int?) : Slot()
-    data object DragHandle : Slot()
-    data object Scaffold : Slot()
+private sealed interface Slot {
+    data class SheetContent(val key: Int?) : Slot
+    data object DragHandle : Slot
+    data object Scaffold : Slot
 }
-

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/components/MessagesReactionButton.kt

@@ -103,11 +103,11 @@ fun MessagesReactionButton(
     }
 }
 
-sealed class MessagesReactionsButtonContent {
-    data class Text(val text: String) : MessagesReactionsButtonContent()
-    data class Icon(@DrawableRes val resourceId: Int) : MessagesReactionsButtonContent()
+sealed interface MessagesReactionsButtonContent {
+    data class Text(val text: String) : MessagesReactionsButtonContent
+    data class Icon(@DrawableRes val resourceId: Int) : MessagesReactionsButtonContent
 
-    data class Reaction(val reaction: AggregatedReaction) : MessagesReactionsButtonContent()
+    data class Reaction(val reaction: AggregatedReaction) : MessagesReactionsButtonContent
 
     val isHighlighted get() = this is Reaction && reaction.isHighlighted
 }

libraries/androidutils/src/main/kotlin/io/element/android/libraries/androidutils/throttler/FirstThrottler.kt

@@ -24,9 +24,9 @@ import android.os.SystemClock
 class FirstThrottler(private val minimumInterval: Long = 800) {
     private var lastDate = 0L
 
-    sealed class CanHandleResult {
-        data object Yes : CanHandleResult()
-        data class No(val shouldWaitMillis: Long) : CanHandleResult()
+    sealed interface CanHandleResult {
+        data object Yes : CanHandleResult
+        data class No(val shouldWaitMillis: Long) : CanHandleResult
 
         fun waitMillis(): Long {
             return when (this) {

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/permalink/PermalinkData.kt

@@ -22,14 +22,14 @@ import android.net.Uri
  * This sealed class represents all the permalink cases.
  * You don't have to instantiate yourself but should use [PermalinkParser] instead.
  */
-sealed class PermalinkData {
+sealed interface PermalinkData {
 
     data class RoomLink(
         val roomIdOrAlias: String,
         val isRoomAlias: Boolean,
         val eventId: String?,
         val viaParameters: List<String>
-    ) : PermalinkData()
+    ) : PermalinkData
 
     /*
      * &room_name=Team2
@@ -47,9 +47,9 @@ sealed class PermalinkData {
         val token: String,
         val privateKey: String,
         val roomType: String?
-    ) : PermalinkData()
+    ) : PermalinkData
 
-    data class UserLink(val userId: String) : PermalinkData()
+    data class UserLink(val userId: String) : PermalinkData
 
-    data class FallbackLink(val uri: Uri, val isLegacyGroupLink: Boolean = false) : PermalinkData()
+    data class FallbackLink(val uri: Uri, val isLegacyGroupLink: Boolean = false) : PermalinkData
 }

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/roomlist/RoomList.kt

@@ -28,9 +28,9 @@ import kotlin.time.Duration
  * Can be retrieved from [RoomListService] methods.
  */
 interface RoomList {
-    sealed class LoadingState {
-        data object NotLoaded : LoadingState()
-        data class Loaded(val numberOfRooms: Int) : LoadingState()
+    sealed interface LoadingState {
+        data object NotLoaded : LoadingState
+        data class Loaded(val numberOfRooms: Int) : LoadingState
     }
 
     /**

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/roomlist/RoomListService.kt

@@ -25,16 +25,16 @@ import kotlinx.coroutines.flow.StateFlow
  */
 interface RoomListService {
 
-    sealed class State {
-        data object Idle : State()
-        data object Running : State()
-        data object Error : State()
-        data object Terminated : State()
+    sealed interface State {
+        data object Idle : State
+        data object Running : State
+        data object Error : State
+        data object Terminated : State
     }
 
-    sealed class SyncIndicator {
-        data object Show : SyncIndicator()
-        data object Hide : SyncIndicator()
+    sealed interface SyncIndicator {
+        data object Show : SyncIndicator
+        data object Hide : SyncIndicator
     }
 
     /**

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/tracing/WriteToFilesConfiguration.kt

@@ -16,7 +16,7 @@
 
 package io.element.android.libraries.matrix.api.tracing
 
-sealed class WriteToFilesConfiguration {
-    data object Disabled : WriteToFilesConfiguration()
-    data class Enabled(val directory: String, val filenamePrefix: String) : WriteToFilesConfiguration()
+sealed interface WriteToFilesConfiguration {
+    data object Disabled : WriteToFilesConfiguration
+    data class Enabled(val directory: String, val filenamePrefix: String) : WriteToFilesConfiguration
 }

libraries/textcomposer/impl/src/main/kotlin/io/element/android/libraries/textcomposer/model/PressEvent.kt

@@ -16,8 +16,8 @@
 
 package io.element.android.libraries.textcomposer.model
 
-sealed class PressEvent {
-    data object PressStart: PressEvent()
-    data object Tapped: PressEvent()
-    data object LongPressEnd: PressEvent()
+sealed interface PressEvent {
+    data object PressStart: PressEvent
+    data object Tapped: PressEvent
+    data object LongPressEnd: PressEvent
 }

libraries/textcomposer/impl/src/main/kotlin/io/element/android/libraries/textcomposer/model/VoiceMessagePlayerEvent.kt

@@ -16,11 +16,11 @@
 
 package io.element.android.libraries.textcomposer.model
 
-sealed class VoiceMessagePlayerEvent {
-    data object Play: VoiceMessagePlayerEvent()
-    data object Pause: VoiceMessagePlayerEvent()
+sealed interface VoiceMessagePlayerEvent {
+    data object Play: VoiceMessagePlayerEvent
+    data object Pause: VoiceMessagePlayerEvent
 
     data class Seek(
         val position: Float
-    ): VoiceMessagePlayerEvent()
+    ): VoiceMessagePlayerEvent
 }

libraries/textcomposer/impl/src/main/kotlin/io/element/android/libraries/textcomposer/model/VoiceMessageState.kt

@@ -19,8 +19,8 @@ package io.element.android.libraries.textcomposer.model
 import kotlinx.collections.immutable.ImmutableList
 import kotlin.time.Duration
 
-sealed class VoiceMessageState {
-    data object Idle: VoiceMessageState()
+sealed interface VoiceMessageState {
+    data object Idle: VoiceMessageState
 
     data class Preview(
         val isSending: Boolean,
@@ -29,10 +29,10 @@ sealed class VoiceMessageState {
         val playbackProgress: Float,
         val time: Duration,
         val waveform: ImmutableList<Float>,
-    ): VoiceMessageState()
+    ): VoiceMessageState
 
     data class Recording(
         val duration: Duration,
         val levels: ImmutableList<Float>,
-    ): VoiceMessageState()
+    ): VoiceMessageState
 }

libraries/textcomposer/impl/src/main/kotlin/io/element/android/libraries/textcomposer/utils/PressState.kt

@@ -19,13 +19,13 @@ package io.element.android.libraries.textcomposer.utils
 /**
  * State of a press gesture.
  */
-internal sealed class PressState {
+internal sealed interface PressState {
     data class Idle(
         val lastPress: Pressing?
-    ) : PressState()
+    ) : PressState
 
-    sealed class Pressing : PressState()
-    data object Tapping : Pressing()
-    data object LongPressing : Pressing()
+    sealed interface Pressing : PressState
+    data object Tapping : Pressing
+    data object LongPressing : Pressing
 }
 

libraries/voicerecorder/api/src/main/kotlin/io/element/android/libraries/voicerecorder/api/VoiceRecorderState.kt

@@ -19,11 +19,11 @@ package io.element.android.libraries.voicerecorder.api
 import java.io.File
 import kotlin.time.Duration
 
-sealed class VoiceRecorderState {
+sealed interface VoiceRecorderState {
     /**
      * The recorder is idle and not recording.
      */
-    data object Idle : VoiceRecorderState()
+    data object Idle : VoiceRecorderState
 
     /**
      * The recorder is currently recording.
@@ -31,7 +31,7 @@ sealed class VoiceRecorderState {
      * @property elapsedTime The elapsed time since the recording started.
      * @property levels The current audio levels of the recording as a fraction of 1.
      */
-    data class Recording(val elapsedTime: Duration, val levels: List<Float>) : VoiceRecorderState()
+    data class Recording(val elapsedTime: Duration, val levels: List<Float>) : VoiceRecorderState
 
     /**
      * The recorder has finished recording.
@@ -46,5 +46,5 @@ sealed class VoiceRecorderState {
         val mimeType: String,
         val waveform: List<Float>,
         val duration: Duration,
-    ) : VoiceRecorderState()
+    ) : VoiceRecorderState
 }

libraries/voicerecorder/impl/src/main/kotlin/io/element/android/libraries/voicerecorder/impl/audio/Audio.kt

@@ -16,13 +16,13 @@
 
 package io.element.android.libraries.voicerecorder.impl.audio
 
-sealed class Audio {
+sealed interface Audio {
     class Data(
         val readSize: Int,
         val buffer: ShortArray,
-    ) : Audio()
+    ) : Audio
 
     data class Error(
         val audioRecordErrorCode: Int
-    ) : Audio()
+    ) : Audio
 }

tests/konsist/src/test/kotlin/io/element/android/tests/konsist/KonsistArchitectureTest.kt

@@ -21,7 +21,9 @@ import com.lemonappdev.konsist.api.ext.list.constructors
 import com.lemonappdev.konsist.api.ext.list.modifierprovider.withSealedModifier
 import com.lemonappdev.konsist.api.ext.list.parameters
 import com.lemonappdev.konsist.api.ext.list.withNameEndingWith
+import com.lemonappdev.konsist.api.ext.list.withoutConstructors
 import com.lemonappdev.konsist.api.ext.list.withoutName
+import com.lemonappdev.konsist.api.ext.list.withoutParents
 import com.lemonappdev.konsist.api.verify.assertEmpty
 import com.lemonappdev.konsist.api.verify.assertTrue
 import org.junit.Test
@@ -55,4 +57,14 @@ class KonsistArchitectureTest {
             .withNameEndingWith("Events")
             .assertEmpty(additionalMessage = "Events class MUST be sealed interface")
     }
+
+    @Test
+    fun `Sealed class without constructor and without parent MUST be sealed interface`() {
+        Konsist.scopeFromProject()
+            .classes()
+            .withSealedModifier()
+            .withoutConstructors()
+            .withoutParents()
+            .assertEmpty(additionalMessage = "Sealed class without constructor MUST be sealed interface")
+    }
 }