From a34692b6f22bef284695f708659c5c7d3cf87d8f Mon Sep 17 00:00:00 2001
From: Chris LaFreniere <40371649+chlafreniere@users.noreply.github.com>
Date: Wed, 3 Apr 2019 18:08:42 -0700
Subject: [PATCH] Fix for dispose method of undefined (#4843)

---
 src/sql/parts/notebook/models/cell.ts | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/sql/parts/notebook/models/cell.ts b/src/sql/parts/notebook/models/cell.ts
index 48c9eed199..104696b2c7 100644
--- a/src/sql/parts/notebook/models/cell.ts
+++ b/src/sql/parts/notebook/models/cell.ts
@@ -490,7 +490,9 @@ export class CellModel implements ICellModel {
 
 	// Dispose and set current future to undefined
 	private disposeFuture() {
-		this._future.dispose();
+		if (this._future) {
+			this._future.dispose();
+		}
 		this._future = undefined;
 	}
 }