From 4ee8bdb762f870351da9be51d13dae6c9328e72f Mon Sep 17 00:00:00 2001
From: Bill Ticehurst <billti@hotmail.com>
Date: Tue, 21 Mar 2017 14:49:20 -0700
Subject: [PATCH] Suppress semantic errors in JS only configured projects

---
 src/server/session.ts | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/src/server/session.ts b/src/server/session.ts
index 262ba8da1da..d35677e1c3d 100644
--- a/src/server/session.ts
+++ b/src/server/session.ts
@@ -25,15 +25,14 @@ namespace ts.server {
         return ((1e9 * seconds) + nanoseconds) / 1000000.0;
     }
 
-    function shouldSkipSematicCheck(project: Project) {
-        if (project.getCompilerOptions().skipLibCheck !== undefined) {
-            return false;
+    function shouldSkipSemanticCheck(project: Project) {
+        if (project.projectKind === ProjectKind.Inferred || project.projectKind === ProjectKind.External) {
+            return project.isJsOnlyProject();
         }
-
-        if ((project.projectKind === ProjectKind.Inferred || project.projectKind === ProjectKind.External) && project.isJsOnlyProject()) {
-            return true;
+        else {
+            // For configured projects, require that skipLibCheck be set also
+            return project.getCompilerOptions().skipLibCheck && project.isJsOnlyProject();
         }
-        return false;
     }
 
     interface FileStart {
@@ -454,7 +453,7 @@ namespace ts.server {
         private semanticCheck(file: NormalizedPath, project: Project) {
             try {
                 let diags: Diagnostic[] = [];
-                if (!shouldSkipSematicCheck(project)) {
+                if (!shouldSkipSemanticCheck(project)) {
                     diags = project.getLanguageService().getSemanticDiagnostics(file);
                 }
 
@@ -562,7 +561,7 @@ namespace ts.server {
 
         private getDiagnosticsWorker(args: protocol.FileRequestArgs, isSemantic: boolean, selector: (project: Project, file: string) => Diagnostic[], includeLinePosition: boolean) {
             const { project, file } = this.getFileAndProject(args);
-            if (isSemantic && shouldSkipSematicCheck(project)) {
+            if (isSemantic && shouldSkipSemanticCheck(project)) {
                 return [];
             }
             const scriptInfo = project.getScriptInfoForNormalizedPath(file);