Tweak tests to use new API and add another warning

Author: gaearon

package.json

@@ -63,6 +63,6 @@
   "dependencies": {
     "lodash": "^3.10.1",
     "react-redux": "^4.0.0",
-    "redux": "^3.0.0"
+    "redux": "^3.2.1"
   }
 }

src/instrument.js

@@ -341,18 +341,30 @@ function unliftStore(liftedStore, liftReducer) {
  */
 export default function instrument(monitorReducer = () => null) {
   return createStore => (reducer, initialState, enhancer) => {
+
     function liftReducer(r) {
       if (typeof r !== 'function') {
-        throw new Error('Expected the nextReducer to be a function.');
+        if (r && typeof r['default'] === 'function') {
+          throw new Error(
+            'Expected the reducer to be a function. ' +
+            'Instead got an object with a "default" field. ' +
+            'Did you pass a module instead of the default export? ' +
+            'Try passing require(...).default instead.'
+          );
+        }
+        throw new Error('Expected the reducer to be a function.');
       }
       return liftReducerWith(r, initialState, monitorReducer);
     }
 
-    const liftedStore = createStore(liftReducer(reducer), undefined, enhancer);
+    const liftedStore = createStore(liftReducer(reducer), enhancer);
     if (liftedStore.liftedStore) {
-      throw new Error('DevTools instrument shouldn\'t be included more than once. ' +
-        'Check your store configuration.');
+      throw new Error(
+        'DevTools instrumentation should not be applied more than once. ' +
+        'Check your store configuration.'
+      );
     }
+
     return unliftStore(liftedStore, liftReducer);
   };
 }

test/instrument.spec.js

@@ -32,7 +32,7 @@ describe('instrument', () => {
   let liftedStore;
 
   beforeEach(() => {
-    store = instrument()(createStore)(counter);
+    store = createStore(counter, instrument());
     liftedStore = store.liftedStore;
   });
 
@@ -156,7 +156,7 @@ describe('instrument', () => {
 
   it('should catch and record errors', () => {
     let spy = spyOn(console, 'error');
-    let storeWithBug = instrument()(createStore)(counterWithBug);
+    let storeWithBug = createStore(counterWithBug, instrument());
 
     storeWithBug.dispatch({ type: 'INCREMENT' });
     storeWithBug.dispatch({ type: 'DECREMENT' });
@@ -180,12 +180,13 @@ describe('instrument', () => {
     expect(() => {
       store.dispatch({ type: undefined });
     }).toThrow(
-      /Actions may not have an undefined/
+      'Actions may not have an undefined "type" property. ' +
+      'Have you misspelled a constant?'
     );
   });
 
   it('should return the last non-undefined state from getState', () => {
-    let storeWithBug = instrument()(createStore)(counterWithBug);
+    let storeWithBug = createStore(counterWithBug, instrument());
     storeWithBug.dispatch({ type: 'INCREMENT' });
     storeWithBug.dispatch({ type: 'INCREMENT' });
     expect(storeWithBug.getState()).toBe(2);
@@ -196,7 +197,7 @@ describe('instrument', () => {
 
   it('should not recompute states on every action', () => {
     let reducerCalls = 0;
-    let monitoredStore = instrument()(createStore)(() => reducerCalls++);
+    let monitoredStore = createStore(() => reducerCalls++, instrument());
     expect(reducerCalls).toBe(1);
     monitoredStore.dispatch({ type: 'INCREMENT' });
     monitoredStore.dispatch({ type: 'INCREMENT' });
@@ -206,7 +207,7 @@ describe('instrument', () => {
 
   it('should not recompute old states when toggling an action', () => {
     let reducerCalls = 0;
-    let monitoredStore = instrument()(createStore)(() => reducerCalls++);
+    let monitoredStore = createStore(() => reducerCalls++, instrument());
     let monitoredLiftedStore = monitoredStore.liftedStore;
 
     expect(reducerCalls).toBe(1);
@@ -249,7 +250,7 @@ describe('instrument', () => {
 
   it('should not recompute states when jumping to state', () => {
     let reducerCalls = 0;
-    let monitoredStore = instrument()(createStore)(() => reducerCalls++);
+    let monitoredStore = createStore(() => reducerCalls++, instrument());
     let monitoredLiftedStore = monitoredStore.liftedStore;
 
     expect(reducerCalls).toBe(1);
@@ -272,10 +273,9 @@ describe('instrument', () => {
     expect(monitoredLiftedStore.getState().computedStates).toBe(savedComputedStates);
   });
 
-
   it('should not recompute states on monitor actions', () => {
     let reducerCalls = 0;
-    let monitoredStore = instrument()(createStore)(() => reducerCalls++);
+    let monitoredStore = createStore(() => reducerCalls++, instrument());
     let monitoredLiftedStore = monitoredStore.liftedStore;
 
     expect(reducerCalls).toBe(1);
@@ -301,7 +301,7 @@ describe('instrument', () => {
     let exportedState;
 
     beforeEach(() => {
-      monitoredStore = instrument()(createStore)(counter);
+      monitoredStore = createStore(counter, instrument());
       monitoredLiftedStore = monitoredStore.liftedStore;
       // Set up state to export
       monitoredStore.dispatch({ type: 'INCREMENT' });
@@ -312,15 +312,15 @@ describe('instrument', () => {
     });
 
     it('should replay all the steps when a state is imported', () => {
-      let importMonitoredStore = instrument()(createStore)(counter);
+      let importMonitoredStore = createStore(counter, instrument());
       let importMonitoredLiftedStore = importMonitoredStore.liftedStore;
 
       importMonitoredLiftedStore.dispatch(ActionCreators.importState(exportedState));
       expect(importMonitoredLiftedStore.getState()).toEqual(exportedState);
     });
 
     it('should replace the existing action log with the one imported', () => {
-      let importMonitoredStore = instrument()(createStore)(counter);
+      let importMonitoredStore = createStore(counter, instrument());
       let importMonitoredLiftedStore = importMonitoredStore.liftedStore;
 
       importMonitoredStore.dispatch({ type: 'DECREMENT' });
@@ -333,12 +333,27 @@ describe('instrument', () => {
 
   it('throws if reducer is not a function', () => {
     expect(() =>
-      instrument()(createStore)()
-    ).toThrow('Expected the nextReducer to be a function.');
+      createStore(undefined, instrument())
+    ).toThrow('Expected the reducer to be a function.');
+  });
+
+  it('warns if the reducer is not a function but has a default field that is', () => {
+    expect(() =>
+      createStore(({ default: () => {} }), instrument())
+    ).toThrow(
+      'Expected the reducer to be a function. ' +
+      'Instead got an object with a "default" field. ' +
+      'Did you pass a module instead of the default export? ' +
+      'Try passing require(...).default instead.'
+    );
   });
+
   it('throws if there are more than one instrument enhancer included', () => {
     expect(() => {
-      store = createStore(counter, undefined, compose(instrument(), instrument()));
-    }).toThrow('DevTools instrument shouldn\'t be included more than once. Check your store configuration.');
+      createStore(counter, compose(instrument(), instrument()))
+    }).toThrow(
+      'DevTools instrumentation should not be applied more than once. ' +
+      'Check your store configuration.'
+    );
   });
 });

test/persistState.spec.js

@@ -39,64 +39,59 @@ describe('persistState', () => {
   };
 
   it('should persist state', () => {
-    const finalCreateStore = compose(instrument(), persistState('id'))(createStore);
-    const store = finalCreateStore(reducer);
+    const store = createStore(reducer, compose(instrument(), persistState('id')));
     expect(store.getState()).toBe(0);
 
     store.dispatch({ type: 'INCREMENT' });
     store.dispatch({ type: 'INCREMENT' });
     expect(store.getState()).toBe(2);
 
-    const store2 = finalCreateStore(reducer);
+    const store2 = createStore(reducer, compose(instrument(), persistState('id')));
     expect(store2.getState()).toBe(2);
   });
 
   it('should not persist state if no session id', () => {
-    const finalCreateStore = compose(instrument(), persistState())(createStore);
-    const store = finalCreateStore(reducer);
+    const store = createStore(reducer, compose(instrument(), persistState()));
     expect(store.getState()).toBe(0);
 
     store.dispatch({ type: 'INCREMENT' });
     store.dispatch({ type: 'INCREMENT' });
     expect(store.getState()).toBe(2);
 
-    const store2 = finalCreateStore(reducer);
+    const store2 = createStore(reducer, compose(instrument(), persistState()));
     expect(store2.getState()).toBe(0);
   });
 
   it('should run with a custom state deserializer', () => {
     const oneLess = state => state === undefined ? -1 : state - 1;
-    const finalCreateStore = compose(instrument(), persistState('id', oneLess))(createStore);
-    const store = finalCreateStore(reducer);
+    const store = createStore(reducer, compose(instrument(), persistState('id', oneLess)));
     expect(store.getState()).toBe(0);
 
     store.dispatch({ type: 'INCREMENT' });
     store.dispatch({ type: 'INCREMENT' });
     expect(store.getState()).toBe(2);
 
-    const store2 = finalCreateStore(reducer);
+    const store2 = createStore(reducer, compose(instrument(), persistState('id', oneLess)));
     expect(store2.getState()).toBe(1);
   });
 
   it('should run with a custom action deserializer', () => {
     const incToDec = action => action.type === 'INCREMENT' ? { type: 'DECREMENT' } : action;
-    const finalCreateStore = compose(instrument(), persistState('id', undefined, incToDec))(createStore);
-    const store = finalCreateStore(reducer);
+    const store = createStore(reducer, compose(instrument(), persistState('id', undefined, incToDec)));
     expect(store.getState()).toBe(0);
 
     store.dispatch({ type: 'INCREMENT' });
     store.dispatch({ type: 'INCREMENT' });
     expect(store.getState()).toBe(2);
 
-    const store2 = finalCreateStore(reducer);
+    const store2 = createStore(reducer, compose(instrument(), persistState('id', undefined, incToDec)));
     expect(store2.getState()).toBe(-2);
   });
 
   it('should warn if read from localStorage fails', () => {
     const spy = expect.spyOn(console, 'warn');
-    const finalCreateStore = compose(instrument(), persistState('id'))(createStore);
     delete global.localStorage.getItem;
-    finalCreateStore(reducer);
+    const store = createStore(reducer, compose(instrument(), persistState('id')));
 
     expect(spy.calls).toContain(
       /Could not read debug session from localStorage/,
@@ -105,11 +100,11 @@ describe('persistState', () => {
 
     spy.restore();
   });
+
   it('should warn if write to localStorage fails', () => {
     const spy = expect.spyOn(console, 'warn');
-    const finalCreateStore = compose(instrument(), persistState('id'))(createStore);
     delete global.localStorage.setItem;
-    const store = finalCreateStore(reducer);
+    const store = createStore(reducer, compose(instrument(), persistState('id')));
 
     store.dispatch({ type: 'INCREMENT' });
     expect(spy.calls).toContain(