From d34dae04d213ed520fa21af333fbca7280c49b03 Mon Sep 17 00:00:00 2001
From: emizzle <ericmastro@status.im>
Date: Sun, 5 Aug 2018 17:51:26 +1000
Subject: [PATCH] DTwitter contract update

Also update the DTwitter contract to correctly include a require statement ensuring only existing users can tweet.
---
 contracts/DTwitter.sol | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/contracts/DTwitter.sol b/contracts/DTwitter.sol
index 1c10066..faa52e2 100644
--- a/contracts/DTwitter.sol
+++ b/contracts/DTwitter.sol
@@ -121,6 +121,8 @@ contract DTwitter {
      * {string} content - the tweet content
      */
     function tweet(string content) public {
+        // ensure the sender has an account
+        require(owners[msg.sender].length > 0);
 
         // get the username hash of the sender's account
         bytes32 usernameHash = owners[msg.sender];