Add preview for expanded state of GroupedEvents.

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

@@ -187,16 +187,21 @@ internal fun aTimelineItemReadReceipts(): TimelineItemReadReceipts {
 }
 
 fun aGroupedEvents(id: Long = 0): TimelineItem.GroupedEvents {
-    val event = aTimelineItemEvent(
+    val event1 = aTimelineItemEvent(
         isMine = true,
         content = aTimelineItemStateEventContent(),
         groupPosition = TimelineItemGroupPosition.None
     )
+    val event2 = aTimelineItemEvent(
+        isMine = true,
+        content = aTimelineItemStateEventContent(body = "Another state event"),
+        groupPosition = TimelineItemGroupPosition.None
+    )
     return TimelineItem.GroupedEvents(
         id = id.toString(),
         events = listOf(
-            event,
-            event,
+            event1,
+            event2,
         ).toImmutableList()
     )
 }

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

@@ -26,9 +26,13 @@ import androidx.compose.ui.res.pluralStringResource
 import io.element.android.features.messages.impl.R
 import io.element.android.features.messages.impl.timeline.TimelineEvents
 import io.element.android.features.messages.impl.timeline.TimelineItemRow
+import io.element.android.features.messages.impl.timeline.aGroupedEvents
 import io.element.android.features.messages.impl.timeline.components.group.GroupHeaderView
 import io.element.android.features.messages.impl.timeline.model.TimelineItem
 import io.element.android.features.messages.impl.timeline.session.SessionState
+import io.element.android.features.messages.impl.timeline.session.aSessionState
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.preview.PreviewsDayNight
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.UserId
 
@@ -138,3 +142,51 @@ private fun TimelineItemGroupedEventsRowContent(
         }
     }
 }
+
+@PreviewsDayNight
+@Composable
+fun TimelineItemGroupedEventsRowContentExpandedPreview() = ElementPreview {
+    TimelineItemGroupedEventsRowContent(
+        isExpanded = true,
+        onExpandGroupClick = {},
+        timelineItem = aGroupedEvents(),
+        highlightedItem = null,
+        showReadReceipts = true,
+        isLastOutgoingMessage = false,
+        sessionState = aSessionState(),
+        onClick = {},
+        onLongClick = {},
+        inReplyToClick = {},
+        onUserDataClick = {},
+        onTimestampClicked = {},
+        onReactionClick = { _, _ -> },
+        onReactionLongClick = { _, _ -> },
+        onMoreReactionsClick = {},
+        onReadReceiptClick = {},
+        eventSink = {},
+    )
+}
+
+@PreviewsDayNight
+@Composable
+fun TimelineItemGroupedEventsRowContentCollapsePreview() = ElementPreview {
+    TimelineItemGroupedEventsRowContent(
+        isExpanded = false,
+        onExpandGroupClick = {},
+        timelineItem = aGroupedEvents(),
+        highlightedItem = null,
+        showReadReceipts = true,
+        isLastOutgoingMessage = false,
+        sessionState = aSessionState(),
+        onClick = {},
+        onLongClick = {},
+        inReplyToClick = {},
+        onUserDataClick = {},
+        onTimestampClicked = {},
+        onReactionClick = { _, _ -> },
+        onReactionLongClick = { _, _ -> },
+        onMoreReactionsClick = {},
+        onReadReceiptClick = {},
+        eventSink = {},
+    )
+}

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/model/event/TimelineItemEventContentProvider.kt

@@ -79,6 +79,8 @@ fun aTimelineItemTextContent() = TimelineItemTextContent(
 
 fun aTimelineItemUnknownContent() = TimelineItemUnknownContent
 
-fun aTimelineItemStateEventContent() = TimelineItemStateEventContent(
-    body = "A state event",
+fun aTimelineItemStateEventContent(
+    body: String = "A state event",
+) = TimelineItemStateEventContent(
+    body = body,
 )