Support Additional arguments for handleAction(s)

    * resolve redux-utilities#148

Author: Xiaohan Zhang

src/__tests__/handleAction-test.js

@@ -65,6 +65,22 @@ describe('handleAction()', () => {
             counter: 10
           });
       });
+
+      it('should should support additional arguments', () => {
+        const { increment } = createActions('INCREMENT');
+
+        const reducer = handleAction(
+          increment, (state, { payload }, extraArg) => ({
+            counter: state.counter + payload + extraArg
+          }), 
+          { counter: 3 });
+
+        const counterBase = 10;
+        expect(reducer(undefined, increment(7), counterBase))
+          .to.deep.equal({
+            counter: 10 + counterBase
+          });
+      });
     });
   });
 

src/__tests__/handleActions-test.js

@@ -147,4 +147,27 @@ describe('handleActions', () => {
         counter: 7
       });
   });
+
+  it('accepts additional arguments', () => {
+    // meaningless base and fix just for testing additional arguments
+    const base = 5;
+    const fix = 1;
+    const incrementAction = createAction('INCREMENT');
+    const reducer = handleActions({
+      [incrementAction]: (
+        { counter }, { payload: amount }, extraArg1, extraArg2
+      ) => {
+        console.log(extraArg1);
+        console.log(extraArg2);
+        return {
+        counter: counter + amount + extraArg1 + extraArg2
+      }
+      }
+    });
+
+    expect(reducer({ counter: 3 }, incrementAction(7), base, fix))
+      .to.deep.equal({
+        counter: 10 + base + fix
+      });
+  });
 });

src/handleAction.js

@@ -11,11 +11,13 @@ export default function handleAction(actionType, reducers, defaultState) {
     ? [reducers, reducers]
     : [reducers.next, reducers.throw].map(reducer => (isNil(reducer) ? identity : reducer));
 
-  return (state = defaultState, action) => {
+  return (state = defaultState, action, ...args) => {
     if (!includes(actionTypes, action.type.toString())) {
       return state;
     }
 
-    return (action.error === true ? throwReducer : nextReducer)(state, action);
+    return (
+      action.error === true ? throwReducer : nextReducer
+    )(state, action, ...args);
   };
 }

src/handleActions.js

@@ -1,10 +1,11 @@
 import handleAction from './handleAction';
 import ownKeys from './ownKeys';
-import reduceReducers from 'reduce-reducers';
 
 export default function handleActions(handlers, defaultState) {
   const reducers = ownKeys(handlers).map(type => handleAction(type, handlers[type]));
-  const reducer = reduceReducers(...reducers);
+  const reducer = (state, action, ...args) => reducers.reduce(
+    (p, r) => r(p, action, ...args), state);
 
-  return (state = defaultState, action) => reducer(state, action);
+  return (state = defaultState, action, ...args) => reducer(state, action, ...args);
 }
+