From 3b7078ec9a7cecc712b6162ca31f11feeb91156c Mon Sep 17 00:00:00 2001
From: Chris Bobbe <cbobbe@plaidypus.com>
Date: Fri, 20 Sep 2019 01:22:00 -0500
Subject: [PATCH] narrowsReducer/eventUpdateMessageFlags: Assert operation is
 add | remove

Adds an assertion to match the type in EventUpdateMessageFlagsAction
in src/actionTypes.js, so that action.operation can only be 'add' or
'remove'.
---
 src/chat/narrowsReducer.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/chat/narrowsReducer.js b/src/chat/narrowsReducer.js
index 8329b285a7c..ded4fae0de0 100644
--- a/src/chat/narrowsReducer.js
+++ b/src/chat/narrowsReducer.js
@@ -74,6 +74,8 @@ const eventUpdateMessageFlags = (state, action) => {
         updates.push({
           [narrowStr]: state[narrowStr].filter(id => !messagesSet.has(id)),
         });
+      } else {
+        throw new Error(`Unexpected operation ${operation} in an EVENT_UPDATE_MESSAGE_FLAGS action`);
       }
     }