Voice message recording enhancements (#2042)

* Use Combine to report AudioRecorder state changes

* AudioRecorder is now using AVAudioEngine instead of AVAudioRecorder

* Stop recording when audio configuration changes

* AudioRecorder error handling

* UnitTests

* Use Accelerate to calculate RMS

UnitTests/Sources/AudioRecorderTests.swift

@@ -0,0 +1,56 @@
+//
+// 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 Combine
+@testable import ElementX
+import Foundation
+import XCTest
+
+@MainActor
+class AudioRecorderTests: XCTestCase {
+    private var audioRecorder: AudioRecorder!
+    private var audioSessionMock: AudioSessionMock!
+    
+    override func setUp() async throws {
+        audioSessionMock = AudioSessionMock()
+        audioSessionMock.requestRecordPermissionClosure = { completion in
+            completion(true)
+        }
+        audioRecorder = AudioRecorder(audioSession: audioSessionMock)
+    }
+    
+    override func tearDown() async throws {
+        await audioRecorder?.cancelRecording()
+    }
+    
+    func testRecordWithoutPermission() async throws {
+        audioSessionMock.requestRecordPermissionClosure = { completion in
+            completion(false)
+        }
+        
+        let deferred = deferFulfillment(audioRecorder.actions) { action in
+            switch action {
+            case .didFailWithError(.recordPermissionNotGranted):
+                return true
+            default:
+                return false
+            }
+        }
+        await audioRecorder.record(with: .uuid(UUID()))
+        try await deferred.fulfill()
+        XCTAssertFalse(audioRecorder.isRecording)
+    }
+}