Performance tests (#1301)

* Add signposts to performance tests.

- Update flow to include support for the migration screen.

* If the welcome screen shows, click on the button.

* Ensure a clean simulator each run.

* Add accessibility identifier for migration screen if required.

* Handle walking into the room and back out again.

* use iphone 14 pro to match what's used in xcode.

* Remove ApplicationTests as duplicated in LoginTests.

We measure app startup time in LoginTests as part of the flow - we may as well avoid spending 60s doing only that measurement in ApplicationTests

* Sleep 10s, the ui is otherwise showing up in random order.

* Revert "Remove ApplicationTests as duplicated in LoginTests."

This reverts commit 8670710315bcd0d6c3c3046f534b32b4c728b837.

* Update script to parse out correct values from results file.

* Allow cancellation of password prompt in any order.

* Remove test timeout, performance tests will always take a while.

* Adjust parsing further

* Remove ApplicationTests.

* Move to a more elegant way to wait for something to disappear.

* Linting.

* Fix unit tests.

---------

Co-authored-by: Doug <douglase@element.io>
Co-authored-by: Doug <6060466+pixlwave@users.noreply.github.com>

ElementX/Sources/Services/Analytics/AnalyticsService.swift

@@ -35,6 +35,10 @@ class AnalyticsService {
     private let client: AnalyticsClientProtocol
     private let appSettings: AppSettings
     private let bugReportService: BugReportServiceProtocol
+    
+    /// A signpost client for performance testing the app. This client doesn't respect the
+    /// `isRunning` state or behave any differently when `start`/`reset` are called.
+    let signpost = Signposter()
 
     init(client: AnalyticsClientProtocol, appSettings: AppSettings, bugReportService: BugReportServiceProtocol) {
         self.client = client

ElementX/Sources/Services/Analytics/Signposter.swift

@@ -0,0 +1,84 @@
+//
+// Copyright 2023 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import OSLog
+
+/// A simple wrapper around OSSignposter for easy performance testing.
+class Signposter {
+    /// The underlying signposter.
+    private let signposter = OSSignposter(subsystem: subsystem, category: category)
+    /// A logger instance to capture any errors.
+    private let logger = Logger(subsystem: subsystem, category: category)
+    
+    /// Signpost name constants.
+    enum Name {
+        static let login: StaticString = "Login"
+        static let sync: StaticString = "Sync"
+        static let roomFlow: StaticString = "RoomFlow"
+    }
+    
+    static let subsystem = "ElementX"
+    static let category = "PerformanceTests"
+    
+    // MARK: - Login
+    
+    private var loginState: OSSignpostIntervalState?
+    
+    func beginLogin() {
+        loginState = signposter.beginInterval(Name.login)
+    }
+    
+    func endLogin() {
+        guard let loginState else {
+            logger.error("Missing login state.")
+            return
+        }
+        
+        signposter.endInterval(Name.login, loginState)
+        self.loginState = nil
+    }
+    
+    // MARK: - Sync
+    
+    private var syncState: OSSignpostIntervalState?
+    
+    func beginSync() {
+        syncState = signposter.beginInterval(Name.sync)
+    }
+    
+    func endSync() {
+        guard let syncState else { return }
+        
+        signposter.endInterval(Name.sync, syncState)
+        self.syncState = nil
+    }
+    
+    // MARK: - Room Flow
+    
+    private var roomFlowState: OSSignpostIntervalState?
+    
+    func beginRoomFlow(_ name: String) {
+        roomFlowState = signposter.beginInterval(Name.roomFlow)
+        signposter.emitEvent("RoomName", "\(name, privacy: .auto(mask: .hash))")
+    }
+    
+    func endRoomFlow() {
+        guard let roomFlowState else { return }
+        
+        signposter.endInterval(Name.roomFlow, roomFlowState)
+        self.roomFlowState = nil
+    }
+}