From f7cc05482b783c48d9bc912ae8821d2d38dbe9bd Mon Sep 17 00:00:00 2001
From: Ryan Cavanaugh <RyanCavanaugh@users.noreply.github.com>
Date: Mon, 23 May 2016 16:25:25 -0700
Subject: [PATCH] Don't lose host 'this'

---
 src/compiler/program.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index c3a79ea58d6..c7dc47b0006 100644
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -980,7 +980,7 @@ namespace ts {
 
         // or load all types from the automatic type import fields
         if (host && host.getDefaultTypeDirectiveNames) {
-            const commonRoot = computeCommonSourceDirectoryOfFilenames(rootFiles, host.getCurrentDirectory(), host.getCanonicalFileName);
+            const commonRoot = computeCommonSourceDirectoryOfFilenames(rootFiles, host.getCurrentDirectory(), f => host.getCanonicalFileName(f));
             if (commonRoot) {
                 return host.getDefaultTypeDirectiveNames(commonRoot);
             }