my project uses both Objective-C and Swift code. When a user logs in, it calls a set of apis for user preference, I have a DataCoordinator.swift class which schedules the API operation and I make this calls from UserDetailViewController.m class to load user preferences. This use to work fine before I migrated my code to Swift 4 using Xcode 9 beta 4. Now when I login it crashes by giving me this error in my DataCoordinator class. Below is a sample of my DataCoordinator and Viewcontroller class.
DataCoordinator.swift
import UIKit
@objcMembers
class DataCoordinator: NSObject {
//MARK:- Private
fileprivate var user = myDataStore.sharedInstance().user
fileprivate var preferenceFetchOperations = [FetchOperation]()
fileprivate func scheduleFetchOperation(_ operation:FetchOperation, inFetchOperations operations:inout [FetchOperation]) {
guard operations.index(of: operation) == nil else { return }
operations.append(operation)
}
fileprivate func completeFetchOperation(_ fetchOperation:FetchOperation, withError error:Error?, andCompletionHandler handler:@escaping FetchCompletionHandler) {
func removeOperation(_ operation:FetchOperation, fromOperations operations:inout [FetchOperation]) {
if operations.count > 0 {
operations.remove(at: operations.index(of: fetchOperation)!)
handler(error)
}
}
if preferenceFetchOperations.contains(fetchOperation) {
removeOperation(fetchOperation, fromOperations: &preferenceFetchOperations)
}
}
fileprivate func schedulePreferencesFetchOperation(_ serviceName:String, fetch:@escaping FetchOperationBlock){
let operation = FetchOperation(name: serviceName, fetch: fetch);
scheduleFetchOperation(operation, inFetchOperations: &preferenceFetchOperations)
}
fileprivate func runOperationsIn(_ fetchOperations:inout [FetchOperation]) {
for var operation in fetchOperations {
guard operation.isActivated == false else { continue }
operation.isActivated = true
operation.execute()
}
}
//MARK:- Non-Private
typealias FetchCompletionHandler = (_ error:Error?)->Void
var numberOfPreferencesFetchCalls:Int {
get { return preferenceFetchOperations.count }
}
// MARK: -
func fetchPreferences(_ completionHandler:@escaping FetchCompletionHandler) -> Void {
defer {
runOperationsIn(&preferenceFetchOperations)
}
schedulePreferencesFetchOperation("com.fetchPreferences.type1") {[unowned self] (operation:FetchOperation) in
WebServiceManager.getType1Detail(for: user) {[unowned self] (error) in
self.completeFetchOperation(operation, withError: error, andCompletionHandler: completionHandler)
}
}
schedulePreferencesFetchOperation("com.fetchPreferences.type2") {[unowned self] (operation:FetchOperation) in
WebServiceManager.getType2Detail(for: user) {[unowned self] (error) in
self.completeFetchOperation(operation, withError: error, andCompletionHandler: completionHandler)
}
}
schedulePreferencesFetchOperation("com.fetchPreferences.type3") {[unowned self] (operation:FetchOperation) in
WebServiceManager.getType3Detail(for: user) {[unowned self] (error) in
self.completeFetchOperation(operation, withError: error, andCompletionHandler: completionHandler)
}
}
schedulePreferencesFetchOperation("com.fetchPreferences.type4") {[unowned self] (operation:FetchOperation) in
WebServiceManager.getType4Detail(for: user) {[unowned self] (error) in
self.completeFetchOperation(operation, withError: error, andCompletionHandler: completionHandler)
}
}
}
}
// MARK:- Fetch Operation Struct
private typealias FetchOperationBlock = (_ operation:FetchOperation)->Void
private struct FetchOperation:Hashable {
fileprivate var runToken = 0
fileprivate let fetchBlock:FetchOperationBlock
let name:String!
var isActivated:Bool {
get {
return runToken == 0 ? false : true
}
mutating set {
if runToken == 0 && newValue == true {
runToken = 1
}
}
}
fileprivate var hashValue: Int {
get {
return name.hashValue
}
}
func execute() -> Void {
fetchBlock(self)
}
init (name:String, fetch:@escaping FetchOperationBlock) {
self.name = name
self.fetchBlock = fetch
}
}
private func ==(lhs: FetchOperation, rhs: FetchOperation) -> Bool {
return lhs.hashValue == rhs.hashValue
}
//This is how I call it in my viewcontrollers viewDidLoad method
__weak UserDetailViewController *weakSelf = self;
[self.dataCoordinator fetchPreferences:^(NSError * _Nullable error) {
if (error == nil) {
[weakSelf didFetchPrefrences];
}
else {
// handle error
}
}];
//completion response
- (void)didFetchPrefrences {
//when api calls complete load data
if (self.dataCoordinator.numberOfPreferencesFetchCalls == 0) {
//Load details
}
}
I'm not sure how to proceed on this, I saw a bug report at https://bugs.swift.org/browse/SR-5119 but it seems to be fixed in Xcode 9 beta 3. Any help is appreciated
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