From 0450dc869d3a4c13854df480a40c3088183177b5 Mon Sep 17 00:00:00 2001
From: Adam Brown <adampsbrown@gmail.com>
Date: Sun, 2 Oct 2022 16:06:42 +0100
Subject: [PATCH] extracting flow extension for starting and ignoring future
 emissions

---
 .../app/dapk/st/core/extensions/FlowExtensions.kt      | 10 ++++------
 .../kotlin/app/dapk/st/messenger/TimelineUseCase.kt    |  6 ++++--
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/core/src/main/kotlin/app/dapk/st/core/extensions/FlowExtensions.kt b/core/src/main/kotlin/app/dapk/st/core/extensions/FlowExtensions.kt
index 2ffc7da..92be2fb 100644
--- a/core/src/main/kotlin/app/dapk/st/core/extensions/FlowExtensions.kt
+++ b/core/src/main/kotlin/app/dapk/st/core/extensions/FlowExtensions.kt
@@ -1,11 +1,7 @@
 package app.dapk.st.core.extensions
 
-import kotlinx.coroutines.InternalCoroutinesApi
-import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.filter
-import kotlinx.coroutines.flow.takeWhile
+import kotlinx.coroutines.flow.*
 
-@OptIn(InternalCoroutinesApi::class)
 suspend fun <T> Flow<T>.firstOrNull(count: Int, predicate: suspend (T) -> Boolean): T? {
     var counter = 0
 
@@ -21,4 +17,6 @@ suspend fun <T> Flow<T>.firstOrNull(count: Int, predicate: suspend (T) -> Boolea
         }
 
     return result
-}
\ No newline at end of file
+}
+
+fun <T> Flow<T>.startAndIgnoreEmissions(): Flow<Boolean> = this.map { false }.onStart { emit(true) }.filter { it }
\ No newline at end of file
diff --git a/features/messenger/src/main/kotlin/app/dapk/st/messenger/TimelineUseCase.kt b/features/messenger/src/main/kotlin/app/dapk/st/messenger/TimelineUseCase.kt
index 629c466..c1d9538 100644
--- a/features/messenger/src/main/kotlin/app/dapk/st/messenger/TimelineUseCase.kt
+++ b/features/messenger/src/main/kotlin/app/dapk/st/messenger/TimelineUseCase.kt
@@ -1,5 +1,6 @@
 package app.dapk.st.messenger
 
+import app.dapk.st.core.extensions.startAndIgnoreEmissions
 import app.dapk.st.matrix.common.RoomId
 import app.dapk.st.matrix.common.RoomMember
 import app.dapk.st.matrix.common.UserId
@@ -7,7 +8,8 @@ import app.dapk.st.matrix.message.MessageService
 import app.dapk.st.matrix.room.RoomService
 import app.dapk.st.matrix.sync.RoomState
 import app.dapk.st.matrix.sync.SyncService
-import kotlinx.coroutines.flow.*
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.combine
 
 internal typealias ObserveTimelineUseCase = (RoomId, UserId) -> Flow<MessengerState>
 
@@ -42,7 +44,7 @@ internal class TimelineUseCaseImpl(
     }
 
     private fun roomDatasource(roomId: RoomId) = combine(
-        syncService.startSyncing().map { false }.onStart { emit(true) }.filter { it },
+        syncService.startSyncing().startAndIgnoreEmissions(),
         syncService.room(roomId)
     ) { _, room -> room }
 }