Merge pull request #41 from davidmarne/strong_mode_rules

Strong mode rules & Action stream

Author: davidmarne

analysis_options.yaml

@@ -1,4 +1,4 @@
 analyzer:
-  strong-mode: true
-  implicit-dynamic: false
-  implicit-casts: false
+  strong-mode:
+    implicit-casts: false
+    implicit-dynamic: false

lib/built_redux.dart

@@ -3,7 +3,6 @@ library built_redux;
 export 'src/action.dart';
 export 'src/reducer_builder.dart';
 export 'src/middleware.dart';
-export 'src/state_transformer.dart';
 export 'src/store.dart';
 export 'src/store_change.dart';
 export 'src/typedefs.dart';

lib/src/action.dart

@@ -30,7 +30,7 @@ class ActionDispatcher<P> {
 
   ActionDispatcher(this._name);
 
-  void setDispatcher(dispatcher) {
+  void setDispatcher(Dispatcher dispatcher) {
     _dispatcher = dispatcher;
   }
 }

lib/src/middleware.dart

@@ -31,9 +31,11 @@ class MiddlewareBuilder<
   var _map = new Map<String,
       MiddlewareHandler<State, StateBuilder, Actions, dynamic>>();
 
-  void add<T>(ActionName<T> aMgr,
-      MiddlewareHandler<State, StateBuilder, Actions, T> handler) {
-    _map[aMgr.name] = handler;
+  void add<Payload>(ActionName<Payload> aMgr,
+      MiddlewareHandler<State, StateBuilder, Actions, Payload> handler) {
+    _map[aMgr.name] = (api, next, action) {
+      handler(api, next, action as Action<Payload>);
+    };
   }
 
   /// [build] returns a [Middleware] function that handles all actions added with [add]

lib/src/reducer_builder.dart

@@ -17,7 +17,9 @@ class ReducerBuilder<State extends Built<State, StateBuilder>,
   /// Registers [reducer] function to the given [actionName]
   void add<Payload>(ActionName<Payload> actionName,
       Reducer<State, StateBuilder, Payload> reducer) {
-    _map[actionName.name] = reducer;
+    _map[actionName.name] = (state, action, builder) {
+      reducer(state, action as Action<Payload>, builder);
+    };
   }
 
   /// [combine] combines this ReducerBuilder with another ReducerBuilder
@@ -127,7 +129,7 @@ class NestedReducerBuilder<
       Reducer<NestedState, NestedStateBuilder, Payload> reducer) {
     _map[actionName.name] = (state, action, builder) => reducer(
           _stateMapper(state),
-          action,
+          action as Action<Payload>,
           _builderMapper(builder),
         );
   }
@@ -144,7 +146,9 @@ class AbstractReducerBuilder<AState, AStateBuilder> {
   /// Registers [reducer] function to the given [actionName]
   void add<Payload>(ActionName<Payload> actionName,
       CReducer<AState, AStateBuilder, Payload> reducer) {
-    _map[actionName.name] = reducer;
+    _map[actionName.name] = (state, action, builder) {
+      reducer(state, action as Action<Payload>, builder);
+    };
   }
 
   Map<String, CReducer<AState, AStateBuilder, dynamic>> build() => _map;
@@ -171,7 +175,7 @@ class ListReducerBuilder<State extends Built<State, StateBuilder>,
       CReducer<BuiltList<T>, ListBuilder<T>, Payload> reducer) {
     _map[actionName.name] = (state, action, builder) => reducer(
           _stateMapper(state),
-          action,
+          action as Action<Payload>,
           _builderMapper(builder),
         );
   }
@@ -194,7 +198,7 @@ class ListMultimapReducerBuilder<State extends Built<State, StateBuilder>,
           reducer) {
     _map[actionName.name] = (state, action, builder) => reducer(
           _stateMapper(state),
-          action,
+          action as Action<Payload>,
           _builderMapper(builder),
         );
   }
@@ -215,7 +219,7 @@ class MapReducerBuilder<State extends Built<State, StateBuilder>,
       CReducer<BuiltMap<K, V>, MapBuilder<K, V>, Payload> reducer) {
     _map[actionName.name] = (state, action, builder) => reducer(
           _stateMapper(state),
-          action,
+          action as Action<Payload>,
           _builderMapper(builder),
         );
   }
@@ -236,7 +240,7 @@ class SetReducerBuilder<State extends Built<State, StateBuilder>,
       CReducer<BuiltSet<T>, SetBuilder<T>, Payload> reducer) {
     _map[actionName.name] = (state, action, builder) => reducer(
           _stateMapper(state),
-          action,
+          action as Action<Payload>,
           _builderMapper(builder),
         );
   }
@@ -259,7 +263,7 @@ class SetMultimapReducerBuilder<State extends Built<State, StateBuilder>,
           reducer) {
     _map[actionName.name] = (state, action, builder) => reducer(
           _stateMapper(state),
-          action,
+          action as Action<Payload>,
           _builderMapper(builder),
         );
   }

lib/src/state_transformer.dart

@@ -7,7 +7,6 @@ import 'action.dart';
 import 'middleware.dart';
 import 'typedefs.dart';
 import 'store_change.dart';
-import 'state_transformer.dart';
 
 /// [Store] is the container of your state. It listens for actions, invokes reducers,
 /// and publishes changes to the state
@@ -34,8 +33,7 @@ class Store<
 
     _actions = actions;
 
-    final MiddlewareApi api =
-        new MiddlewareApi<State, StateBuilder, Actions>(this);
+    final api = new MiddlewareApi<State, StateBuilder, Actions>(this);
 
     // setup the dispatch chain
     ActionHandler handler = (action) {
@@ -68,7 +66,7 @@ class Store<
   }
 
   /// [dispose] removes closes both the dispatch and subscription stream
-  dispose() {
+  void dispose() {
     _stateController.close();
     _state = null;
     _actions = null;
@@ -79,7 +77,7 @@ class Store<
   void replaceState(State state) {
     if (_state != state) {
       _stateController.add(new StoreChange<State, StateBuilder, dynamic>(
-          state, _state, new Action('replaceState', null)));
+          state, _state, new Action<Null>('replaceState', null)));
       _state = state;
     }
   }
@@ -104,12 +102,26 @@ class Store<
   Stream<SubstateChange<Substate>> substateStream<Substate>(
     StateMapper<State, StateBuilder, Substate> mapper,
   ) =>
-      _stateController.stream.transform(new StateChangeTransformer(mapper));
+      stream
+          .map((c) => new SubstateChange<Substate>(
+                mapper(c.prev),
+                mapper(c.next),
+              ))
+          .where((c) => c.prev != c.next);
 
   /// [nextSubstate] is a stream which has a payload of the next subState value, rather than the SubstateChange event
   Stream<Substate> nextSubstate<Substate>(
     StateMapper<State, StateBuilder, Substate> mapper,
   ) =>
       substateStream(mapper)
           .map((SubstateChange<Substate> change) => change.next);
+
+  /// [actionStream] returns a stream the fires when a state change is caused by the action
+  /// with the name provided. Check out built_redux_rx if you are looking for streams to actions that do not
+  /// necessarily result in state changes.
+  Stream<StoreChange<State, StateBuilder, Payload>> actionStream<Payload>(
+          ActionName<Payload> actionName) =>
+      stream
+          .where((c) => c.action.name == actionName.name)
+          .map((c) => c as StoreChange<State, StateBuilder, Payload>);
 }

lib/src/store.dart

@@ -39,11 +39,13 @@ class StoreChangeHandlerBuilder<
   /// Registers [handler] function to the given [actionName]
   void add<Payload>(ActionName<Payload> actionName,
       StoreChangeHandler<Payload, State, StateBuilder> handler) {
-    _map[actionName.name] = handler;
+    _map[actionName.name] = (change) {
+      handler(change as StoreChange<State, StateBuilder, Payload>);
+    };
   }
 
   /// [build] sets up a subscription to the registered actions
-  build(Store<State, StateBuilder, Actions> store) {
+  void build(Store<State, StateBuilder, Actions> store) {
     _subscription = store.stream
         .listen((StoreChange<State, StateBuilder, dynamic> storeChange) {
       var handler = _map[storeChange.action.name];
@@ -52,7 +54,7 @@ class StoreChangeHandlerBuilder<
   }
 
   /// [dispose] cancels the subscription to the store
-  dispose() {
+  void dispose() {
     _subscription.cancel();
   }
 }

lib/src/store_change.dart

@@ -22,3 +22,15 @@ typedef NextActionHandler Middleware<
     State extends Built<State, StateBuilder>,
     StateBuilder extends Builder<State, StateBuilder>,
     Actions extends ReduxActions>(MiddlewareApi<State, StateBuilder, Actions> api);
+
+/// [SubstateChange] is the payload for `StateChangeTransformer`'s stream. It contains
+/// the previous and next value of the state resulting from the mapper provided to `StateChangeTransformer`
+class SubstateChange<Substate> {
+  Substate prev;
+  Substate next;
+  SubstateChange(this.prev, this.next);
+}
+
+/// [StateMapper] takes a state model and maps it to the values one cares about
+typedef Substate StateMapper<State extends Built<State, StateBuilder>,
+    StateBuilder extends Builder<State, StateBuilder>, Substate>(State state);

lib/src/typedefs.dart

@@ -1,5 +1,5 @@
 name: built_redux
-version: 7.1.0
+version: 7.2.0
 description:
   A state management library written in dart that enforces immutability
 authors: