1 files changed, 44 insertions, 0 deletions
diff --git a/kotlinx-coroutines-core/jvm/test/flow/StateFlowUpdateStressTest.kt b/kotlinx-coroutines-core/jvm/test/flow/StateFlowUpdateStressTest.kt
new file mode 100644
index 00000000..660ed0aa
--- /dev/null
+++ b/kotlinx-coroutines-core/jvm/test/flow/StateFlowUpdateStressTest.kt
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2016-2021 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.coroutines.flow
+
+import kotlinx.coroutines.*
+import org.junit.*
+import kotlin.test.*
+import kotlin.test.Test
+
+class StateFlowUpdateStressTest : TestBase() {
+    private val iterations = 1_000_000 * stressTestMultiplier
+
+    @get:Rule
+    public val executor = ExecutorRule(2)
+
+    @Test
+    fun testUpdate() = doTest { update { it + 1 } }
+
+    @Test
+    fun testUpdateAndGet() = doTest { updateAndGet { it + 1 } }
+
+    @Test
+    fun testGetAndUpdate() = doTest { getAndUpdate { it + 1 } }
+
+    private fun doTest(increment: MutableStateFlow<Int>.() -> Unit) = runTest {
+        val flow = MutableStateFlow(0)
+        val j1 = launch(Dispatchers.Default) {
+            repeat(iterations / 2) {
+                flow.increment()
+            }
+        }
+
+        val j2 = launch(Dispatchers.Default) {
+            repeat(iterations / 2) {
+                flow.increment()
+            }
+        }
+
+        joinAll(j1, j2)
+        assertEquals(iterations, flow.value)
+    }
+}