Add utitlity for stringContains

src/server/editorServices.ts

@@ -1205,7 +1205,7 @@ namespace ts.server {
             projectRootPath?: NormalizedPath) {
             let searchPath = asNormalizedPath(getDirectoryPath(info.fileName));
 
-            while (!projectRootPath || searchPath.indexOf(projectRootPath) >= 0) {
+            while (!projectRootPath || stringContains(searchPath, projectRootPath)) {
                 const canonicalSearchPath = normalizedPathToPath(searchPath, this.currentDirectory, this.toCanonicalFileName);
                 const tsconfigFileName = asNormalizedPath(combinePaths(searchPath, "tsconfig.json"));
                 let result = action(tsconfigFileName, combinePaths(canonicalSearchPath, "tsconfig.json"));

src/server/session.ts

@@ -1608,7 +1608,7 @@ namespace ts.server {
             }
 
             // No need to analyze lib.d.ts
-            const fileNamesInProject = fileNames.filter(value => value.indexOf("lib.d.ts") < 0);
+            const fileNamesInProject = fileNames.filter(value => !stringContains(value, "lib.d.ts"));
             if (fileNamesInProject.length === 0) {
                 return;
             }

src/server/typingsInstaller/nodeTypingsInstaller.ts

@@ -88,7 +88,7 @@ namespace ts.server.typingsInstaller {
             this.npmPath = npmLocation !== undefined ? npmLocation : getDefaultNPMLocation(process.argv[0]);
 
             // If the NPM path contains spaces and isn't wrapped in quotes, do so.
-            if (this.npmPath.indexOf(" ") !== -1 && this.npmPath[0] !== `"`) {
+            if (stringContains(this.npmPath, " ") && this.npmPath[0] !== `"`) {
                 this.npmPath = `"${this.npmPath}"`;
             }
             if (this.log.isEnabled()) {