Try to avoid possible [unowned self] crash on iOS 13.4 and Xcode 11.4

ClassyFlux.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'ClassyFlux'
-  s.version          = '1.21.0'
+  s.version          = '1.21.1'
   s.summary          = 'Flux implementation on Swift'
   s.homepage         = 'https://github.com/kzlekk/ClassyFlux'
   s.license          = { :type => 'MIT', :file => 'LICENSE' }

ClassyFlux.xcodeproj/project.pbxproj

@@ -434,7 +434,7 @@
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
-				MARKETING_VERSION = 1.21.0;
+				MARKETING_VERSION = 1.21.1;
 				PRODUCT_BUNDLE_IDENTIFIER = org.kzlekk.ClassyFlux;
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SDKROOT = macosx;
@@ -461,7 +461,7 @@
 					"@executable_path/Frameworks",
 					"@loader_path/Frameworks",
 				);
-				MARKETING_VERSION = 1.21.0;
+				MARKETING_VERSION = 1.21.1;
 				PRODUCT_BUNDLE_IDENTIFIER = org.kzlekk.ClassyFlux;
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SDKROOT = macosx;

Flux/FluxAggregator.swift

@@ -63,7 +63,9 @@ public class FluxAggregator {
     /// - Parameter observingKeyPaths: The list of KeyPath describing the fields in particular state object which should trigger state change handlers.
     public func register<State>(store: FluxStore<State>, observing observingKeyPaths: Set<PartialKeyPath<State>> = Set(), queue: OperationQueue = .main) {
         storage.register(instance: store as FluxStore<State>)
-        observers[store.token] = store.addObserver(for: .stateDidChange, queue: queue) { [unowned self] state, changedKeyPaths in
+        observers[store.token] = store.addObserver(for: .stateDidChange, queue: queue) { [weak self] state, changedKeyPaths in
+            guard let self = self else { return }
+
             guard observingKeyPaths.isEmpty || !observingKeyPaths.isDisjoint(with: changedKeyPaths) else {
                 return
             }

Flux/FluxMiddleware.swift

@@ -101,7 +101,8 @@ extension FluxWorker where Self: FluxMiddleware {
     /// - Parameter action: The type of the actions to associate with handler.
     /// - Parameter compose: The closure that will be invoked when the action received.
     public func registerComposer<Action: FluxAction>(for action: Action.Type, compose: @escaping (_ owner: Self, _ action: Action) -> FluxPassthroughAction) {
-        registerComposer(for: Action.self) { [unowned self] (action) -> FluxPassthroughAction in
+        registerComposer(for: Action.self) { [weak self] (action) -> FluxPassthroughAction in
+            guard let self = self else { return .next(action) }
             return compose(self, action)
         }
     }
@@ -110,7 +111,8 @@ extension FluxWorker where Self: FluxMiddleware {
     /// - Parameter action: The type of the actions to associate with handler.
     /// - Parameter intercept: The closure that will be invoked when the action received.
     public func registerInterceptor<Action: FluxAction>(for action: Action.Type, intercept: @escaping (_ owner: Self, _ action: Action) -> Void) {
-        registerComposer(for: Action.self) { [unowned self] (action) -> FluxPassthroughAction in
+        registerComposer(for: Action.self) { [weak self] (action) -> FluxPassthroughAction in
+            guard let self = self else { return .next(action) }
             intercept(self, action)
             return .stop()
         }
@@ -120,7 +122,8 @@ extension FluxWorker where Self: FluxMiddleware {
     /// - Parameter action: The type of the actions to associate with handler.
     /// - Parameter execute: The closure that will be invoked when the action received.
     public func registerHandler<Action: FluxAction>(for action: Action.Type, handle: @escaping (_ owner: Self, _ action: Action) -> Void) {
-        registerHandler(for: Action.self) { [unowned self] (action) -> Void in
+        registerHandler(for: Action.self) { [weak self] (action) -> Void in
+            guard let self = self else { return }
             handle(self, action)
         }
     }