From 75e729a8a56cc71b857d1f175d2dc50992e73c9c Mon Sep 17 00:00:00 2001
From: Scott Phillips <scott.phillips@sailpoint.com>
Date: Fri, 7 Jul 2017 17:53:19 -0500
Subject: [PATCH] fix(@ngtools/webpack): Race condition between invalidate &
 populateWebpackResolver

---
 packages/@ngtools/webpack/src/compiler_host.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/@ngtools/webpack/src/compiler_host.ts b/packages/@ngtools/webpack/src/compiler_host.ts
index 7c56c50fcfe4..e0b4fc05ce7f 100644
--- a/packages/@ngtools/webpack/src/compiler_host.ts
+++ b/packages/@ngtools/webpack/src/compiler_host.ts
@@ -188,7 +188,8 @@ export class WebpackCompilerHost implements ts.CompilerHost {
 
   invalidate(fileName: string): void {
     fileName = this._resolve(fileName);
-    if (fileName in this._files) {
+    const result = this.readFile(fileName);
+    if (!result) {
       this._files[fileName] = null;
       this._changedFiles[fileName] = true;
     }