Example setup and teardown in Secrets UI tests

SecretsTouchUITests.swift

class SecretsTouchUITests: XCTestCase {

    var testDirectoryURL: URL!
    var testDocumentURL: URL!
    
    func documentName() -> String? {
        return "testDoc1"
    }
    
    override func setUp() {
        super.setUp()
        
        self.continueAfterFailure = false
        
        let folderURL = sharedFolderURL()
        testDirectoryURL = temporaryDirectoryAtURL(folderURL)
        
        if let docName = documentName() {
            guard let docURL = Bundle(for: SecretsTouchUITests.self).url(forResource: docName, withExtension: "secrets") else {
                XCTFail("Failed to get URL for \(docName). Are you sure you included it in the test bundle?")
                fatalError()
            }
            
            testDocumentURL = testDirectoryURL.appendingPathComponent(docURL.lastPathComponent)
            XCTAssertNoThrow( try FileManager.default.copyItem(at: docURL, to: testDocumentURL), "Failed to copy document to shared folder")
        }
        else {
            self.testDocumentURL = testDirectoryURL.appendingPathComponent("NewDoc.secrets")
        }
        
        let app = XCUIApplication()
        var args: [String] = []
        args.append(contentsOf: ["-ResetDefaults", "YES"])
        args.append(contentsOf: ["-com.apple.CoreData.ConcurrencyDebug", "1"])
        
        if FileManager.default.fileExists(atPath: testDocumentURL.path) {
            args.append(contentsOf: ["-OpenDocumentAt", testDocumentURL.path])
        }
        else {
            args.append(contentsOf: ["-SetupNewDocumentAt", testDocumentURL.path])
        }
        app.launchArguments = args
        app.launch()
    }
    
    override func tearDown() {
        // Tidy up by removing the test directory
        try? FileManager.default.removeItem(at: testDirectoryURL)
        super.tearDown()
    }
}