Commit

Carthage/Checkouts/TrueTime.swift/Tests/NTPIntegrationSpec.swift

@@ -0,0 +1,69 @@
+//
+//  NTPIntegrationSpec.swift
+//  TrueTime
+//
+//  Created by Michael Sanders on 8/1/16.
+//  Copyright © 2016 Instacart. All rights reserved.
+//
+
+@testable import TrueTime
+import Nimble
+import Quick
+
+final class NTPIntegrationSpec: QuickSpec {
+    override func spec() {
+        describe("fetchIfNeeded") {
+            it("should ignore outliers") {
+                self.testReferenceTimeOutliers()
+            }
+        }
+    }
+}
+
+private extension NTPIntegrationSpec {
+    func testReferenceTimeOutliers() {
+        let clients = (0..<100).map { _ in TrueTimeClient() }
+        waitUntil(timeout: 60) { done in
+            var results: [ReferenceTimeResult?] = Array(repeating: nil, count: clients.count)
+            let start = NSDate()
+            let finish = {
+                let end = NSDate()
+                let results = results.compactMap { $0 }
+                let times = results.compactMap { try? $0.get() }
+                let errors: [Error] = results.compactMap {
+                    guard case let .failure(failure) = $0 else { return nil }
+
+                    return failure
+                }
+                expect(times).notTo(beEmpty(), description: "Expected times, got: \(errors)")
+                print("Got \(times.count) times for \(results.count) results")
+
+                let sortedTimes = times.sorted {
+                    $0.time.timeIntervalSince1970 < $1.time.timeIntervalSince1970
+                }
+
+                if !sortedTimes.isEmpty {
+                    let medianTime = sortedTimes[sortedTimes.count / 2]
+                    let maxDelta = end.timeIntervalSince1970 - start.timeIntervalSince1970
+                    for time in times {
+                        let delta = abs(time.time.timeIntervalSince1970 -
+                                        medianTime.time.timeIntervalSince1970)
+                        expect(delta) <= maxDelta
+                    }
+                }
+
+                done()
+            }
+
+            for (idx, client) in clients.enumerated() {
+                client.start(pool: ["time.apple.com"])
+                client.fetchIfNeeded { result in
+                    results[idx] = result
+                    if !results.contains(where: { $0 == nil }) {
+                        finish()
+                    }
+                }
+            }
+        }
+    }
+}