Move Date.now() into actions to have pure reducers (#2324)

Reducers shouldn't have side effect. Date.now() is a side effect and should be done in action creators.

lib/actions/sessions.js

@@ -21,6 +21,7 @@ import {
 export function addSession({uid, shell, pid, cols, rows, splitDirection}) {
   return (dispatch, getState) => {
     const {sessions} = getState();
+    const now = Date.now();
     dispatch({
       type: SESSION_ADD,
       uid,
@@ -29,7 +30,8 @@ export function addSession({uid, shell, pid, cols, rows, splitDirection}) {
       cols,
       rows,
       splitDirection,
-      activeUid: sessions.activeUid
+      activeUid: sessions.activeUid,
+      now
     });
   };
 }
@@ -54,6 +56,7 @@ export function addSessionData(uid, data) {
       data,
       effect() {
         const session = getState().sessions.sessions[uid];
+        const now = Date.now();
         if (session) {
           const enterKey = data.indexOf('\n') > 0;
           const url = enterKey ? isUrl(session.shell, data) : null;
@@ -68,7 +71,8 @@ export function addSessionData(uid, data) {
         dispatch({
           type: SESSION_PTY_DATA,
           uid,
-          data
+          data,
+          now
         });
       }
     });
@@ -127,12 +131,14 @@ export function resizeSession(uid, cols, rows) {
     const {termGroups} = getState();
     const group = findBySession(termGroups, uid);
     const isStandaloneTerm = !group.parentUid && !group.children.length;
+    const now = Date.now();
     dispatch({
       type: SESSION_RESIZE,
       uid,
       cols,
       rows,
       isStandaloneTerm,
+      now,
       effect() {
         rpc.emit('resize', {uid, cols, rows});
       }

lib/reducers/sessions.js

@@ -96,7 +96,7 @@ const reducer = (state = initialState, action) => {
       return state.setIn(['sessions', action.uid], state.sessions[action.uid].merge({
         rows: action.rows,
         cols: action.cols,
-        resizeAt: Date.now()
+        resizeAt: action.now
       }));
 
     case SESSION_SET_CWD:

lib/reducers/ui.js

@@ -216,7 +216,7 @@ const reducer = (state = initial, action) => {
       state_ = state.merge({
         activeUid: action.uid,
         openAt: {
-          [action.uid]: Date.now()
+          [action.uid]: action.now
         }
       }, {deep: true});
       break;
@@ -231,7 +231,7 @@ const reducer = (state = initial, action) => {
       state_ = state.merge({
         rows: action.rows,
         cols: action.cols,
-        resizeAt: Date.now()
+        resizeAt: action.now
       });
       break;
 
@@ -264,11 +264,8 @@ const reducer = (state = initial, action) => {
         break;
       }
 
-      // current time for comparisons
-      const now = Date.now();
-
       // if first data events after open, ignore
-      if (now - state.openAt[action.uid] < 1000) {
+      if (action.now - state.openAt[action.uid] < 1000) {
         break;
       }
 
@@ -276,7 +273,7 @@ const reducer = (state = initial, action) => {
       // proximity of a resize event, since we
       // expect to get data packets from the resize
       // of the ptys as a result
-      if (!state.resizeAt || now - state.resizeAt > 1000) {
+      if (!state.resizeAt || action.now - state.resizeAt > 1000) {
         state_ = state.merge({
           activityMarkers: {
             [action.uid]: true