From 7c5a2ae8e0fb81e758fe261a602332d9447bcc5d Mon Sep 17 00:00:00 2001
From: Karishma Chadha <kchadha@scratch.mit.edu>
Date: Tue, 5 Jun 2018 15:17:28 -0400
Subject: [PATCH] Add check that block associated with comment actually exists.

---
 src/engine/target.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/engine/target.js b/src/engine/target.js
index 3faab5d4c..2e3b67789 100644
--- a/src/engine/target.js
+++ b/src/engine/target.js
@@ -209,7 +209,13 @@ class Target extends EventEmitter {
                 width, height, minimized);
             if (blockId) {
                 newComment.blockId = blockId;
-                this.blocks.getBlock(blockId).comment = id;
+                const blockWithComment = this.blocks.getBlock(blockId);
+                if (blockWithComment) {
+                    blockWithComment.comment = id;
+                } else {
+                    log.warn(`Could not find block with id ${blockId
+                    } associated with commentId: ${id}`);
+                }
             }
             this.comments[id] = newComment;
         }