From 7cd1deb8a0be05e5aaffa339cc9e43ba82914831 Mon Sep 17 00:00:00 2001
From: Tomas Weiss <tomasw@salsitasoft.com>
Date: Fri, 1 Apr 2016 16:10:45 +0200
Subject: [PATCH] implementing replaying flag to mark actions which are
 actually replayed

---
 src/instrument.js | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/instrument.js b/src/instrument.js
index 3b6d5678..04a4745a 100644
--- a/src/instrument.js
+++ b/src/instrument.js
@@ -59,7 +59,7 @@ const INIT_ACTION = { type: '@@INIT' };
 /**
  * Computes the next entry in the log by applying an action.
  */
-function computeNextEntry(reducer, action, state, error) {
+function computeNextEntry(reducer, action, state, error, replaying) {
   if (error) {
     return {
       state,
@@ -70,7 +70,7 @@ function computeNextEntry(reducer, action, state, error) {
   let nextState = state;
   let nextError;
   try {
-    nextState = reducer(state, action);
+    nextState = reducer(state, action, replaying);
   } catch (err) {
     nextError = err.toString();
     if (typeof window === 'object' && typeof window.chrome !== 'undefined') {
@@ -97,7 +97,8 @@ function recomputeStates(
   committedState,
   actionsById,
   stagedActionIds,
-  skippedActionIds
+  skippedActionIds,
+  replaying
 ) {
   // Optimization: exit early and return the same reference
   // if we know nothing could have changed.
@@ -120,7 +121,7 @@ function recomputeStates(
     const shouldSkip = skippedActionIds.indexOf(actionId) > -1;
     const entry = shouldSkip ?
       previousEntry :
-      computeNextEntry(reducer, action, previousState, previousError);
+      computeNextEntry(reducer, action, previousState, previousError, replaying);
 
     nextComputedStates.push(entry);
   }
@@ -170,6 +171,10 @@ function liftReducerWith(reducer, initialCommittedState, monitorReducer) {
     // value whenever we feel like we don't have to recompute the states.
     let minInvalidatedStateIndex = 0;
 
+    // For now, potentially any action except PERFORM_ACTION is considered
+    // as replay
+    let replaying = true;
+
     switch (liftedAction.type) {
       case ActionTypes.RESET: {
         // Get back to the state the store was created with.
@@ -245,6 +250,10 @@ function liftReducerWith(reducer, initialCommittedState, monitorReducer) {
         stagedActionIds = [...stagedActionIds, actionId];
         // Optimization: we know that only the new action needs computing.
         minInvalidatedStateIndex = stagedActionIds.length - 1;
+
+        // This is the first time Action is actually performed, therefore
+        // we don't consider this replay
+        replaying = false;
         break;
       }
       case ActionTypes.IMPORT_STATE: {
@@ -262,6 +271,8 @@ function liftReducerWith(reducer, initialCommittedState, monitorReducer) {
         break;
       }
       case '@@redux/INIT': {
+        replaying = false;
+
         // Always recompute states on hot reload and init.
         minInvalidatedStateIndex = 0;
         break;
@@ -281,7 +292,8 @@ function liftReducerWith(reducer, initialCommittedState, monitorReducer) {
       committedState,
       actionsById,
       stagedActionIds,
-      skippedActionIds
+      skippedActionIds,
+      replaying
     );
     monitorState = monitorReducer(monitorState, liftedAction);
     return {