From 092bb66d03b5200cc2818011b0c09acb33620cf9 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@gmail.com>
Date: Sun, 27 Sep 2015 20:13:38 +0300
Subject: [PATCH] Add performance regression tests

---
 test/devTools.spec.js | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/test/devTools.spec.js b/test/devTools.spec.js
index 672fb8b9..af47f858 100644
--- a/test/devTools.spec.js
+++ b/test/devTools.spec.js
@@ -212,4 +212,35 @@ describe('devTools', () => {
     storeWithBug.dispatch({ type: 'SET_UNDEFINED' });
     expect(storeWithBug.getState()).toBe(2);
   });
+
+  it('should not recompute states on every action', () => {
+    let reducerCalls = 0;
+    let monitoredStore = devTools()(createStore)(() => reducerCalls++);
+    expect(reducerCalls).toBe(1);
+    monitoredStore.dispatch({ type: 'INCREMENT' });
+    monitoredStore.dispatch({ type: 'INCREMENT' });
+    monitoredStore.dispatch({ type: 'INCREMENT' });
+    expect(reducerCalls).toBe(4);
+  });
+
+  it('should not recompute states when jumping to state', () => {
+    let reducerCalls = 0;
+    let monitoredStore = devTools()(createStore)(() => reducerCalls++);
+    let monitoredDevToolsStore = monitoredStore.devToolsStore;
+
+    expect(reducerCalls).toBe(1);
+    monitoredStore.dispatch({ type: 'INCREMENT' });
+    monitoredStore.dispatch({ type: 'INCREMENT' });
+    monitoredStore.dispatch({ type: 'INCREMENT' });
+    expect(reducerCalls).toBe(4);
+
+    monitoredDevToolsStore.dispatch(ActionCreators.jumpToState(0));
+    expect(reducerCalls).toBe(4);
+
+    monitoredDevToolsStore.dispatch(ActionCreators.jumpToState(1));
+    expect(reducerCalls).toBe(4);
+
+    monitoredDevToolsStore.dispatch(ActionCreators.jumpToState(3));
+    expect(reducerCalls).toBe(4);
+  });
 });