Merge pull request #155 from ReactiveCocoa/action-retaining

Make `Action` retain its state property.

Author: mdiep

Sources/Action.swift

@@ -78,6 +78,9 @@ public final class Action<Input, Output, Error: Swift.Error> {
 	public init<State: PropertyProtocol>(state property: State, enabledIf isEnabled: @escaping (State.Value) -> Bool, _ execute: @escaping (State.Value, Input) -> SignalProducer<Output, Error>) {
 		deinitToken = Lifetime.Token()
 		lifetime = Lifetime(deinitToken)
+		
+		// Retain the `property` for the created `Action`.
+		lifetime.ended.observeCompleted { _ = property }
 
 		executeClosure = { state, input in execute(state as! State.Value, input) }
 

Tests/ReactiveSwiftTests/ActionSpec.swift

@@ -58,6 +58,26 @@ class ActionSpec: QuickSpec {
 				action.errors.observeValues { errors.append($0) }
 				action.completed.observeValues { completedCount += 1 }
 			}
+			
+			it("should retain the state property") {
+				var property: MutableProperty<Bool>? = MutableProperty(false)
+				weak var weakProperty = property
+				
+				var action: Action<(), (), NoError>? = Action(state: property!, enabledIf: { _ in true }) { _ in
+					return .empty
+				}
+				
+				expect(weakProperty).toNot(beNil())
+				
+				property = nil
+				expect(weakProperty).toNot(beNil())
+				
+				action = nil
+				expect(weakProperty).to(beNil())
+				
+				// Mute "unused variable" warning.
+				_ = action
+			}
 
 			it("should be disabled and not executing after initialization") {
 				expect(action.isEnabled.value) == false