vapor · tanner0101 · Apr 23, 2019 · Apr 11, 2019
diff --git a/Package.swift b/Package.swift
@@ -12,7 +12,7 @@ let package = Package(
     ],
     dependencies: [
         /// Event-driven network application framework for high performance protocol servers & clients, non-blocking.
-        .package(url: "https://github.com/apple/swift-nio.git", from: "1.12.0"),
+        .package(url: "https://github.com/apple/swift-nio.git", from: "1.14.1"),
     ],
     targets: [
         .target(name: "Async", dependencies: ["NIO"]),

diff --git a/Sources/Async/Collection+Future.swift b/Sources/Async/Collection+Future.swift
@@ -1,15 +1,15 @@
-extension Collection where Element: FutureType {
+extension Collection {
     /// Maps a collection of same-type `Future`s.
     ///
     /// See `Future.map`
-    public func map<T>(to type: T.Type, on worker: Worker, _ callback: @escaping ([Element.Expectation]) throws -> T) -> Future<T> {
+    public func map<S, T>(to type: T.Type, on worker: Worker, _ callback: @escaping ([S]) throws -> T) -> Future<T> where Element == Future<S> {
         return flatten(on: worker).map(to: T.self, callback)
     }
 
     /// Maps a collection of same-type `Future`s.
     ///
     /// See `Future.flatMap`
-    public func flatMap<T>(to type: T.Type, on worker: Worker, _ callback: @escaping ([Element.Expectation]) throws -> Future<T>) -> Future<T> {
+    public func flatMap<S, T>(to type: T.Type, on worker: Worker, _ callback: @escaping ([S]) throws -> Future<T>) -> Future<T> where Element == Future<S> {
         return flatten(on: worker).flatMap(to: T.self, callback)
     }
 }

diff --git a/Sources/Async/Future+DoCatch.swift b/Sources/Async/Future+DoCatch.swift
@@ -48,7 +48,7 @@ extension Future {
     }
 }
 
-extension Collection where Element: FutureType {
+extension Collection {
     /// Adds a callback for handling this `[Future]`'s result when it becomes available.
     ///
     ///     futureStrings.do { strings in
@@ -58,7 +58,7 @@ extension Collection where Element: FutureType {
     ///     }
     ///
     /// - warning: Don't forget to use `catch` to handle the error case.
-    public func `do`(on worker: Worker, _ callback: @escaping ([Element.Expectation]) -> ()) -> Future<[Element.Expectation]> {
+    public func `do`<T>(on worker: Worker, _ callback: @escaping ([T]) -> ()) -> Future<[T]> where Element == Future<T> {
         return self.flatten(on: worker).do(callback)
     }
 
@@ -72,7 +72,7 @@ extension Collection where Element: FutureType {
     ///
     /// - note: Will *only* be executed if an error occurs. Successful results will not call this handler.
     @discardableResult
-    public func `catch`(on worker: Worker,_ callback: @escaping (Error) -> ()) -> Future<[Element.Expectation]> {
+    public func `catch`<T>(on worker: Worker,_ callback: @escaping (Error) -> ()) -> Future<[T]> where Element == Future<T> {
         return self.flatten(on: worker).catch(callback)
     }
 
@@ -89,7 +89,7 @@ extension Collection where Element: FutureType {
     ///
     /// - note: Will be executed on both success and failure, but will not receive any input.
     @discardableResult
-    public func always(on worker: Worker,_ callback: @escaping () -> ()) -> Future<[Element.Expectation]> {
+    public func always<T>(on worker: Worker,_ callback: @escaping () -> ()) -> Future<[T]> where Element == Future<T> {
         return self.flatten(on: worker).always(callback)
     }
 }

diff --git a/Sources/Async/Future+Flatten.swift b/Sources/Async/Future+Flatten.swift
@@ -49,58 +49,17 @@ extension Collection where Element == LazyFuture<Void> {
     }
 }
 
-extension Collection where Element: FutureType {
+extension Collection {
     /// Flattens an array of futures into a future with an array of results.
     /// - note: the order of the results will match the order of the futures in the input array.
-    public func flatten(on worker: Worker) -> Future<[Element.Expectation]> {
-        let eventLoop = worker.eventLoop
-
-        // Avoid unnecessary work
-        guard count > 0 else {
-            return eventLoop.newSucceededFuture(result: [])
-        }
-
-        let resultPromise: EventLoopPromise<[Element.Expectation]> = eventLoop.newPromise()
-        var promiseFulfilled = false
-
-        let expectedCount = self.count
-        var fulfilledCount = 0
-        var results = Array<Element.Expectation?>(repeating: nil, count: expectedCount)
-        for (index, future) in self.enumerated() {
-            future.addAwaiter { result in
-                let work: () -> Void = {
-                    guard !promiseFulfilled else { return }
-                    switch result {
-                    case .success(let result):
-                        results[index] = result
-                        fulfilledCount += 1
-
-                        if fulfilledCount == expectedCount {
-                            promiseFulfilled = true
-                            // Forcibly unwrapping is okay here, because we know that each result has been filled.
-                            resultPromise.succeed(result: results.map { $0! })
-                        }
-                    case .error(let error):
-                        promiseFulfilled = true
-                        resultPromise.fail(error: error)
-                    }
-                }
-
-                if future.eventLoop === eventLoop {
-                    work()
-                } else {
-                    eventLoop.execute(work)
-                }
-            }
-        }
-        return resultPromise.futureResult
+    public func flatten<T>(on worker: Worker) -> Future<[T]> where Element == Future<T> {
+        return Future.whenAll(Array(self), eventLoop: worker.eventLoop)
     }
 }
 
 extension Collection where Element == Future<Void> {
     /// Flattens an array of void futures into a single one.
     public func flatten(on worker: Worker) -> Future<Void> {
-        let flatten: Future<[Void]> = self.flatten(on: worker)
-        return flatten.map(to: Void.self) { _ in return }
+        return Future.andAll(Array(self), eventLoop: worker.eventLoop)
     }
 }