From 0ec9f0d3bb2ab8ce55e7bbbf131ef6d022cd44c6 Mon Sep 17 00:00:00 2001
From: Cyrus Najmabadi <cyrusn@microsoft.com>
Date: Sun, 14 Dec 2014 22:43:26 -0800
Subject: [PATCH] Check tree invariants during fourslash tests.

---
 src/harness/fourslash.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/harness/fourslash.ts b/src/harness/fourslash.ts
index 0eca1981292..9147ffbc7c0 100644
--- a/src/harness/fourslash.ts
+++ b/src/harness/fourslash.ts
@@ -1363,6 +1363,8 @@ module FourSlash {
 
         private checkPostEditInvariants() {
             var incrementalSourceFile = this.languageService.getSourceFile(this.activeFile.fileName);
+            Utils.assertInvariants(incrementalSourceFile, /*parent:*/ undefined);
+
             var incrementalSyntaxDiagnostics = JSON.stringify(Utils.convertDiagnostics(incrementalSourceFile.getSyntacticDiagnostics()));
 
             // Check syntactic structure