Ensure takeItem can return null values

cashapp · Nov 3, 2022 · f91b176 · f91b176
1 parent ff1959f
commit f91b176
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Showing 2 changed files with 11 additions and 4 deletions.
diff --git a/src/commonMain/kotlin/app/cash/turbine/channel.kt b/src/commonMain/kotlin/app/cash/turbine/channel.kt
@@ -156,8 +156,10 @@ internal fun <T> ReceiveChannel<T>.takeEventUnsafe(): Event<T>? {
  * @throws AssertionError if the next event was completion or an error, or no event.
  */
 public fun <T> ReceiveChannel<T>.takeItem(name: String? = null): T {
-  val event = takeEvent()
-  return (event as? Event.Item)?.value ?: unexpectedEvent(name, event, "item")
+  return when (val event = takeEvent()) {
+    is Event.Item -> event.value
+    else -> unexpectedEvent(name, event, "item")
+  }
 }
 
 /**

diff --git a/src/commonTest/kotlin/app/cash/turbine/TurbineTest.kt b/src/commonTest/kotlin/app/cash/turbine/TurbineTest.kt
@@ -18,6 +18,7 @@ package app.cash.turbine
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
+import kotlin.test.assertNull
 import kotlin.test.assertSame
 import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.CoroutineScope
@@ -160,9 +161,11 @@ class TurbineTest {
   @Test
   fun awaitItem() = runTest {
     val item = Any()
-    val channel = Turbine<Any>()
+    val channel = Turbine<Any?>()
     channel.add(item)
+    channel.add(null)
     assertSame(item, channel.awaitItem())
+    assertNull(channel.awaitItem())
   }
 
   @Test
@@ -245,9 +248,11 @@ class TurbineTest {
   @Test
   fun takeItem() = withTestScope {
     val item = Any()
-    val channel = Turbine<Any>()
+    val channel = Turbine<Any?>()
     channel.add(item)
+    channel.add(null)
     assertSame(item, channel.takeItem())
+    assertNull(channel.takeItem())
   }
 
   @Test