From edb51a961ce15d0cfeefe78f071f506321f2280b Mon Sep 17 00:00:00 2001
From: "Aeneas Rekkas (arekkas)" <aeneas@ory.am>
Date: Fri, 11 Nov 2016 12:27:01 +0100
Subject: [PATCH] add neverSkipReducer option to undoable, resolves #129

---
 README.md          |  2 ++
 src/reducer.js     | 19 ++++++++++++-------
 test/index.spec.js |  5 +++++
 3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index d4505b3..dc85f19 100644
--- a/README.md
+++ b/README.md
@@ -159,6 +159,8 @@ undoable(reducer, {
   initTypes: ['@@redux-undo/INIT'] // history will be (re)set upon init action type
 
   debug: false, // set to `true` to turn on debugging
+
+  neverSkipReducer: false, // prevent undoable from skipping the reducer on undo/redo
 })
 ```
 
diff --git a/src/reducer.js b/src/reducer.js
index 5487c80..390f810 100644
--- a/src/reducer.js
+++ b/src/reducer.js
@@ -127,7 +127,8 @@ export default function undoable (reducer, rawConfig = {}) {
     jumpToPastType: rawConfig.jumpToPastType || ActionTypes.JUMP_TO_PAST,
     jumpToFutureType: rawConfig.jumpToFutureType || ActionTypes.JUMP_TO_FUTURE,
     jumpType: rawConfig.jumpType || ActionTypes.JUMP,
-    clearHistoryType: rawConfig.clearHistoryType || ActionTypes.CLEAR_HISTORY
+    clearHistoryType: rawConfig.clearHistoryType || ActionTypes.CLEAR_HISTORY,
+    neverSkipReducer: false
   }
 
   return (state = config.history, action = {}) => {
@@ -149,6 +150,10 @@ export default function undoable (reducer, rawConfig = {}) {
       }
     }
 
+    const skipReducer = (res) => config.neverSkipReducer
+      ? { ...res, present: reducer(res, action) }
+      : res
+
     let res
     switch (action.type) {
       case undefined:
@@ -158,37 +163,37 @@ export default function undoable (reducer, rawConfig = {}) {
         res = undo(history)
         debug.log('perform undo')
         debug.end(res)
-        return res
+        return skipReducer(res)
 
       case config.redoType:
         res = redo(history)
         debug.log('perform redo')
         debug.end(res)
-        return res
+        return skipReducer(res)
 
       case config.jumpToPastType:
         res = jumpToPast(history, action.index)
         debug.log(`perform jumpToPast to ${action.index}`)
         debug.end(res)
-        return res
+        return skipReducer(res)
 
       case config.jumpToFutureType:
         res = jumpToFuture(history, action.index)
         debug.log(`perform jumpToFuture to ${action.index}`)
         debug.end(res)
-        return res
+        return skipReducer(res)
 
       case config.jumpType:
         res = jump(history, action.index)
         debug.log(`perform jump to ${action.index}`)
         debug.end(res)
-        return res
+        return skipReducer(res)
 
       case config.clearHistoryType:
         res = createHistory(history.present)
         debug.log('perform clearHistory')
         debug.end(res)
-        return res
+        return skipReducer(res)
 
       default:
         res = reducer(history.present, action)
diff --git a/test/index.spec.js b/test/index.spec.js
index daa2895..6cacaf0 100644
--- a/test/index.spec.js
+++ b/test/index.spec.js
@@ -5,6 +5,11 @@ import undoable, { ActionCreators, excludeAction, includeAction, isHistory } fro
 const decrementActions = ['DECREMENT']
 
 runTests('Default config')
+runTests('Never skip reducer', {
+  undoableConfig: {
+    neverSkipReducer: false
+  }
+})
 runTests('No Init types', {
   undoableConfig: {
     initTypes: []