From 5db096d8998edeac8f045aa162cdea72e1e978ff Mon Sep 17 00:00:00 2001
From: Robert Holt <rjmholt_msft@outlook.com>
Date: Tue, 20 Mar 2018 22:16:06 -0700
Subject: [PATCH] Defend HelpCompletion from null message from VSCode

---
 src/features/HelpCompletion.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/features/HelpCompletion.ts b/src/features/HelpCompletion.ts
index 997bf00593..368acc91b1 100644
--- a/src/features/HelpCompletion.ts
+++ b/src/features/HelpCompletion.ts
@@ -44,6 +44,10 @@ export class HelpCompletionFeature implements IFeature {
     }
 
     public onEvent(changeEvent: TextDocumentChangeEvent): void {
+        if (!changeEvent) {
+            return;
+        }
+
         this.helpCompletionProvider.updateState(
             changeEvent.document,
             changeEvent.contentChanges[0].text,