performance: dont update by default

README.md

@@ -47,7 +47,8 @@ export let withStore = connect(store)
 ```tsx
 import { withStore } from './store'
 
-let MyComponent = withStore()(({ store }) =>
+                            // Update the component when `today` changes
+let MyComponent = withStore('today')(({ store }) =>
   <div>
     Hello! Today is {store.get('today')}
     <button onClick={() => store.set('today')(new Date)}>Update Date</button>
@@ -73,7 +74,7 @@ store
 
 ### Lensed connects
 
-Instead of updating your React component when anything on the model changed, you can subscribe just to specific properties on your model. Let's modify our React example to only update when `today` changes:
+Instead of updating your React component when anything on the model changed, you subscribe just to specific properties on your model. Let's modify our React example to only update when `today` changes:
 
 ```tsx
 let MyComponent = withStore('today')(

src/react.tsx

@@ -16,13 +16,9 @@ export function connect<Actions extends object>(store: Store<Actions>) {
 
       return class extends React.Component<Omit<Props, 'store'>> {
         componentDidMount() {
-          if (listenOn.length) {
-            state = listenOn.map(key =>
-              store.on(key).subscribe(() => this.forceUpdate())
-            )
-          } else {
-            state = [store.all().subscribe(() => this.forceUpdate())]
-          }
+          state = listenOn.map(key =>
+            store.on(key).subscribe(() => this.forceUpdate())
+          )
         }
         componentWillUnmount() {
           state.forEach(_ => _.dispose())

test/stateful.tsx

@@ -41,19 +41,27 @@ let MyComponentWithLens = connect(store)('isTrue')(
 )
 
 test('[stateful] it should render a component', t =>
-  withElement(MyComponent, _ =>
+  withElement(MyComponentWithLens, _ =>
     t.regex(_.innerHTML, /True/)
   )
 )
 
 test('[stateful] it should update the component', t =>
-  withElement(MyComponent, _ => {
+  withElement(MyComponentWithLens, _ => {
     t.regex(_.innerHTML, /True/)
     Simulate.click(_.querySelector('button')!)
     t.regex(_.innerHTML, /False/)
   })
 )
 
+test('[stateful] it should not update the component if it has no lens', t =>
+  withElement(MyComponent, _ => {
+    t.regex(_.innerHTML, /False/)
+    Simulate.click(_.querySelector('button')!)
+    t.regex(_.innerHTML, /False/)
+  })
+)
+
 // nb: test order matters because store is shared!
 test('[stateful] it should support lenses', t =>
   withElement(MyComponentWithLens, _ => {

test/stateless.tsx

@@ -29,19 +29,27 @@ let MyComponentWithLens = connect(store)('isTrue')(({ store }) =>
 )
 
 test('[stateless] it should render a component', t =>
-  withElement(MyComponent, _ =>
+  withElement(MyComponentWithLens, _ =>
     t.regex(_.innerHTML, /True/)
   )
 )
 
 test('[stateless] it should update the component', t =>
-  withElement(MyComponent, _ => {
+  withElement(MyComponentWithLens, _ => {
     t.regex(_.innerHTML, /True/)
     Simulate.click(_.querySelector('button')!)
     t.regex(_.innerHTML, /False/)
   })
 )
 
+test('[stateless] it should not update the component if it has no lens', t =>
+  withElement(MyComponent, _ => {
+    t.regex(_.innerHTML, /False/)
+    Simulate.click(_.querySelector('button')!)
+    t.regex(_.innerHTML, /False/)
+  })
+)
+
 // nb: test order matters because store is shared!
 test('[stateless] it should support lenses', t =>
   withElement(MyComponentWithLens, _ => {