From c5eebfcc55b4fd18916fa47d4be2f4fd2dec8eb3 Mon Sep 17 00:00:00 2001
From: Supasate Choochaisri <supasate.c@gmail.com>
Date: Fri, 28 Dec 2018 00:37:44 +0700
Subject: [PATCH] Add double-rendering test for immutable and
 seamless-immutable

---
 test/ConnectedRouter.test.js | 114 ++++++++++++++++++++++++++++++++++-
 1 file changed, 113 insertions(+), 1 deletion(-)

diff --git a/test/ConnectedRouter.test.js b/test/ConnectedRouter.test.js
index a2dabd8d..af05a0b5 100644
--- a/test/ConnectedRouter.test.js
+++ b/test/ConnectedRouter.test.js
@@ -178,7 +178,7 @@ describe('ConnectedRouter', () => {
       history.push('/new-location')
       expect(renderCount).toBe(2)
     })
-  }) 
+  })
 
   describe('with immutable structure', () => {
     let ConnectedRouter
@@ -243,6 +243,62 @@ describe('ConnectedRouter', () => {
 
       expect(onLocationChangedSpy.mock.calls).toHaveLength(3)
     })
+
+    it('only renders one time when mounted', () => {
+      let renderCount = 0
+
+      const RenderCounter = () => {
+        renderCount++
+        return null
+      }
+
+      mount(
+        <Provider store={store}>
+          <ConnectedRouter {...props}>
+              <Route path="/" component={RenderCounter} />
+          </ConnectedRouter>
+        </Provider>
+      )
+
+      expect(renderCount).toBe(1)
+    })
+
+    it('does not render again when non-related action is fired', () => {
+      // Initialize the render counter variable
+      let renderCount = 0
+
+      // Create redux store with router state
+      store = createStore(
+        combineReducers({
+          incrementReducer: (state = 0, action = {}) => {
+            if (action.type === 'testAction')
+              return ++state
+
+            return state
+          },
+          router: connectRouter(history)
+        }),
+        compose(applyMiddleware(routerMiddleware(history)))
+      )
+
+
+      const RenderCounter = () => {
+        renderCount++
+        return null
+      }
+
+      mount(
+        <Provider store={store}>
+          <ConnectedRouter {...props}>
+              <Route path="/" component={RenderCounter} />
+          </ConnectedRouter>
+        </Provider>
+      )
+
+      store.dispatch({ type: 'testAction' })
+      history.push('/new-location')
+      expect(renderCount).toBe(2)
+    })
   })
 
   describe('with seamless immutable structure', () => {
@@ -290,6 +346,62 @@ describe('ConnectedRouter', () => {
 
       expect(onLocationChangedSpy.mock.calls).toHaveLength(2)
     })
+
+    it('only renders one time when mounted', () => {
+      let renderCount = 0
+
+      const RenderCounter = () => {
+        renderCount++
+        return null
+      }
+
+      mount(
+        <Provider store={store}>
+          <ConnectedRouter {...props}>
+              <Route path="/" component={RenderCounter} />
+          </ConnectedRouter>
+        </Provider>
+      )
+
+      expect(renderCount).toBe(1)
+    })
+
+    it('does not render again when non-related action is fired', () => {
+      // Initialize the render counter variable
+      let renderCount = 0
+
+      // Create redux store with router state
+      store = createStore(
+        combineReducers({
+          incrementReducer: (state = 0, action = {}) => {
+            if (action.type === 'testAction')
+              return ++state
+
+            return state
+          },
+          router: connectRouter(history)
+        }),
+        compose(applyMiddleware(routerMiddleware(history)))
+      )
+
+
+      const RenderCounter = () => {
+        renderCount++
+        return null
+      }
+
+      mount(
+        <Provider store={store}>
+          <ConnectedRouter {...props}>
+              <Route path="/" component={RenderCounter} />
+          </ConnectedRouter>
+        </Provider>
+      )
+
+      store.dispatch({ type: 'testAction' })
+      history.push('/new-location')
+      expect(renderCount).toBe(2)
+    })
   })
 
   describe('Redux DevTools', () => {