RFC: Nesting

Tests/LinuxMain.swift

@@ -26,6 +26,7 @@ import XCTest
 @testable import ServiceLauncherTests
 
 XCTMain([
-    testCase(Tests.allTests),
+    testCase(LifeycleTests.allTests),
+    testCase(TopLevelTests.allTests),
 ])
 #endif

Tests/ServiceLauncherTests/Helpers.swift

@@ -0,0 +1,101 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftServiceLauncher open source project
+//
+// Copyright (c) 2019-2020 Apple Inc. and the SwiftServiceLauncher project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftServiceLauncher project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Foundation
+import NIO
+import NIOConcurrencyHelpers
+import ServiceLauncher
+
+class GoodItem: LifecycleItem {
+    let queue = DispatchQueue(label: "GoodItem", attributes: .concurrent)
+
+    let id: String
+    let startDelay: Double
+    let shutdownDelay: Double
+
+    var state = State.idle
+    let stateLock = Lock()
+
+    init(id: String = UUID().uuidString,
+         startDelay: Double = Double.random(in: 0.01 ... 0.1),
+         shutdownDelay: Double = Double.random(in: 0.01 ... 0.1)) {
+        self.id = id
+        self.startDelay = startDelay
+        self.shutdownDelay = shutdownDelay
+    }
+
+    var label: String {
+        return self.id
+    }
+
+    func start(callback: @escaping (Error?) -> Void) {
+        self.queue.asyncAfter(deadline: .now() + self.startDelay) {
+            self.stateLock.withLock { self.state = .started }
+            callback(nil)
+        }
+    }
+
+    func shutdown(callback: @escaping (Error?) -> Void) {
+        self.queue.asyncAfter(deadline: .now() + self.shutdownDelay) {
+            self.stateLock.withLock { self.state = .shutdown }
+            callback(nil)
+        }
+    }
+
+    enum State {
+        case idle
+        case started
+        case shutdown
+    }
+}
+
+class NIOItem {
+    let id: String
+    let eventLoopGroup: EventLoopGroup
+    let startDelay: Int64
+    let shutdownDelay: Int64
+
+    var state = State.idle
+    let stateLock = Lock()
+
+    init(eventLoopGroup: EventLoopGroup,
+         id: String = UUID().uuidString,
+         startDelay: Int64 = Int64.random(in: 10 ... 20),
+         shutdownDelay: Int64 = Int64.random(in: 10 ... 20)) {
+        self.id = id
+        self.eventLoopGroup = eventLoopGroup
+        self.startDelay = startDelay
+        self.shutdownDelay = shutdownDelay
+    }
+
+    func start() -> EventLoopFuture<Void> {
+        return self.eventLoopGroup.next().scheduleTask(in: .milliseconds(self.startDelay)) {
+            self.stateLock.withLock { self.state = .started }
+        }.futureResult
+    }
+
+    func shutdown() -> EventLoopFuture<Void> {
+        return self.eventLoopGroup.next().scheduleTask(in: .milliseconds(self.shutdownDelay)) {
+            self.stateLock.withLock { self.state = .shutdown }
+        }.futureResult
+    }
+
+    enum State {
+        case idle
+        case started
+        case shutdown
+    }
+}
+
+struct TestError: Error {}

Tests/ServiceLauncherTests/LifecycleTests+XCTest.swift

@@ -22,15 +22,13 @@ import XCTest
 /// Do NOT edit this file directly as it will be regenerated automatically when needed.
 ///
 
-extension Tests {
-    static var allTests: [(String, (Tests) -> () throws -> Void)] {
+extension LifeycleTests {
+    static var allTests: [(String, (LifeycleTests) -> () throws -> Void)] {
         return [
             ("testStartThenShutdown", testStartThenShutdown),
             ("testImmediateShutdown", testImmediateShutdown),
             ("testBadStartup", testBadStartup),
             ("testBadShutdown", testBadShutdown),
-            ("testStartAndWait", testStartAndWait),
-            ("testBadStartAndWait", testBadStartAndWait),
             ("testShutdownInOrder", testShutdownInOrder),
             ("testSync", testSync),
             ("testAyncBarrier", testAyncBarrier),