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diff --git a/kotlinx-coroutines-debug/src/junit4/CoroutinesTimeout.kt b/kotlinx-coroutines-debug/src/junit4/CoroutinesTimeout.kt
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+/*
+ * Copyright 2016-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.coroutines.debug.junit4
+
+import kotlinx.coroutines.debug.*
+import org.junit.rules.*
+import org.junit.runner.*
+import org.junit.runners.model.*
+import java.util.concurrent.*
+
+/**
+ * Coroutines timeout rule for JUnit4 that is applied to all methods in the class.
+ * This rule is very similar to [Timeout] rule: it runs tests in a separate thread,
+ * fails tests after the given timeout and interrupts test thread.
+ *
+ * Additionally, this rule installs [DebugProbes] and dumps all coroutines at the moment of the timeout.
+ * It may cancel coroutines on timeout if [cancelOnTimeout] set to `true`.
+ *
+ * Example of usage:
+ * ```
+ * class HangingTest {
+ *
+ *   @Rule
+ *   @JvmField
+ *   val timeout = CoroutinesTimeout.seconds(5)
+ *
+ *   @Test
+ *   fun testThatHangs() = runBlocking {
+ *     ...
+ *     delay(Long.MAX_VALUE) // somewhere deep in the stack
+ *     ...
+ *   }
+ * }
+ * ```
+ */
+public class CoroutinesTimeout(
+    private val testTimeoutMs: Long,
+    private val cancelOnTimeout: Boolean = false
+) : TestRule {
+
+    init {
+        require(testTimeoutMs > 0) { "Expected positive test timeout, but had $testTimeoutMs" }
+    }
+
+    companion object {
+        /**
+         * Creates [CoroutinesTimeout] rule with the given timeout in seconds.
+         */
+        public fun seconds(seconds: Int, cancelOnTimeout: Boolean = false): CoroutinesTimeout =
+            seconds(seconds.toLong(), cancelOnTimeout)
+
+        /**
+         * Creates [CoroutinesTimeout] rule with the given timeout in seconds.
+         */
+        public fun seconds(seconds: Long, cancelOnTimeout: Boolean = false): CoroutinesTimeout =
+            CoroutinesTimeout(TimeUnit.SECONDS.toMillis(seconds), cancelOnTimeout) // Overflow is properly handled by TimeUnit
+    }
+
+    /**
+     * @suppress suppress from Dokka
+     */
+    override fun apply(base: Statement, description: Description): Statement =
+        CoroutinesTimeoutStatement(base, description, testTimeoutMs, cancelOnTimeout)
+}