charlieInDen

import CoreLocation
struct PointOfInterest: Codable, Equatable {
    var name: String
}
class PointOfInterestSample {
    var tableView: UITableView = UITableView()
    var tableValues:[PointOfInterest]?
    
    func handleError(_ error: Error?) -> Void {
        print(error!)

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protocol APIRequest {
    associatedtype RequestDataType
    associatedtype ResponseDataType
    func makeRequest(from data: RequestDataType) throws -> URLRequest
    func parseResponse(data: Data) throws -> ResponseDataType
}

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struct PointsOfInterestRequest: APIRequest {
    enum RequestError: Error {
        case invalidCoordinate
        case unknown
    }
    func makeRequest(from coordinate: CLLocationCoordinate2D) throws -> URLRequest {
        guard CLLocationCoordinate2DIsValid(coordinate) else {
            throw RequestError.invalidCoordinate
        }
        var components = URLComponents(string: "https://example.com/locations")!

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class APIRequestLoader<T: APIRequest> {
    let apiRequest: T
    let urlSession: URLSession
    
    init(apiRequest: T, urlSession: URLSession = .shared) {
        self.apiRequest = apiRequest
        self.urlSession = urlSession
    }

    func loadAPIRequest(requestData: T.RequestDataType,

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//Unit test :- Prepare URLRequest -> Parse Response
class PointOfInterestRequestTests: XCTestCase {
    let request = PointsOfInterestRequest()
    func testMakingURLRequest() throws {
        let coordinate = CLLocationCoordinate2D(latitude: 37.3293, longitude: -121.8893)
        let urlRequest = try request.makeRequest(from: coordinate)
        
        XCTAssertEqual(urlRequest.url?.scheme, "https")
        XCTAssertEqual(urlRequest.url?.host, "example.com")
        XCTAssertEqual(urlRequest.url?.query, "lat=37.3293&long=-121.8893")

charlieInDen

//Unit test :- Prepare URLRequest -> Parse Response
class PointOfInterestRequestTests: XCTestCase {
    let request = PointsOfInterestRequest()
    func testMakingURLRequest() throws {
        let coordinate = CLLocationCoordinate2D(latitude: 37.3293, longitude: -121.8893)
        let urlRequest = try request.makeRequest(from: coordinate)
        
        XCTAssertEqual(urlRequest.url?.scheme, "https")
        XCTAssertEqual(urlRequest.url?.host, "example.com")
        XCTAssertEqual(urlRequest.url?.query, "lat=37.3293&long=-121.8893")

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class MockURLProtocol: URLProtocol {
    static var requestHandler: ((URLRequest) throws -> (HTTPURLResponse, Data))?
    override func startLoading() {
        guard let handler = MockURLProtocol.requestHandler else {
            XCTFail("Received unexpected request with no handler set")
            return
        }
        do {
            let (response, data) = try handler(request)
            client?.urlProtocol(self, didReceive: response, cacheStoragePolicy: .notAllowed)

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class CurrentLocationProvider {
    static let authChangedNotification = Notification.Name("AuthChanged")
    func notifyAuthChanged() {
        let name = CurrentLocationProvider.authChangedNotification
        NotificationCenter.default.post(name: name, object: self)
    }
}


class PointsOfInterestTableViewController {

charlieInDen

class CurrentLocationProvider {
    static let authChangedNotification = Notification.Name("AuthChanged")
    
    let notificationCenter: NotificationCenter
    init(notificationCenter: NotificationCenter = .default) {
        self.notificationCenter = notificationCenter
    }
    func notifyAuthChanged() {
        let name = CurrentLocationProvider.authChangedNotification
        notificationCenter.post(name: name, object: self)

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class PointsOfInterestTableViewControllerTests: XCTestCase {
    func testNotification() {
        let notificationCenter = NotificationCenter()
        let observer = PointsOfInterestTableViewController(notificationCenter:
            notificationCenter)
        XCTAssertFalse(observer.didHandleNotification)
        //       Notification posted to just this center, isolating the test
        let name = CurrentLocationProvider.authChangedNotification
        notificationCenter.post(name: name, object: nil)
        XCTAssertTrue(observer.didHandleNotification)