From 5829ca82d0a06cc46738b1566bcbcda4d74b2a30 Mon Sep 17 00:00:00 2001
From: Jason Ramsay <jasonra@microsoft.com>
Date: Fri, 9 Dec 2016 14:44:08 -0800
Subject: [PATCH] use localUse local updatedFileNames - this way we'll know
 that set of names is definitely cleared

---
 src/server/project.ts | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/server/project.ts b/src/server/project.ts
index 005e26a1bc8..392008a9fd6 100644
--- a/src/server/project.ts
+++ b/src/server/project.ts
@@ -675,10 +675,12 @@ namespace ts.server {
                 isInferred: this.projectKind === ProjectKind.Inferred,
                 options: this.getCompilerOptions()
             };
+            const updatedFileNames = this.updatedFileNames;
+            this.updatedFileNames = undefined;
             // check if requested version is the same that we have reported last time
             if (this.lastReportedFileNames && lastKnownVersion === this.lastReportedVersion) {
-                // if current structure version is the same - return info witout any changes
-                if (this.projectStructureVersion == this.lastReportedVersion && !this.updatedFileNames) {
+                // if current structure version is the same - return info without any changes
+                if (this.projectStructureVersion == this.lastReportedVersion && !updatedFileNames) {
                     return { info, projectErrors: this.projectErrors };
                 }
                 // compute and return the difference
@@ -687,7 +689,7 @@ namespace ts.server {
 
                 const added: string[] = [];
                 const removed: string[] = [];
-                const updated: string[] = getOwnKeys(this.updatedFileNames);
+                const updated: string[] = getOwnKeys(updatedFileNames);
                 for (const id in currentFiles) {
                     if (!hasProperty(lastReportedFileNames, id)) {
                         added.push(id);
@@ -700,7 +702,6 @@ namespace ts.server {
                 }
                 this.lastReportedFileNames = currentFiles;
                 this.lastReportedVersion = this.projectStructureVersion;
-                this.updatedFileNames = undefined;
                 return { info, changes: { added, removed, updated }, projectErrors: this.projectErrors };
             }
             else {