Optimize performance of maps

src/server/client.ts

@@ -21,7 +21,7 @@ namespace ts.server {
 
     export class SessionClient implements LanguageService {
         private sequence: number = 0;
-        private lineMaps: ts.Map<number[]> = {};
+        private lineMaps: ts.Map<number[]> = ts.createMap<number[]>();
         private messages: string[] = [];
         private lastRenameEntry: RenameEntry;
 

src/server/editorServices.ts

@@ -130,7 +130,7 @@ namespace ts.server {
             const path = toPath(containingFile, this.host.getCurrentDirectory(), this.getCanonicalFileName);
             const currentResolutionsInFile = cache.get(path);
 
-            const newResolutions: Map<T> = {};
+            const newResolutions = createMap<T>();
             const resolvedModules: R[] = [];
             const compilerOptions = this.getCompilationSettings();
 
@@ -378,7 +378,7 @@ namespace ts.server {
     export interface ProjectOptions {
         // these fields can be present in the project file
         files?: string[];
-        wildcardDirectories?: ts.Map<ts.WatchDirectoryFlags>;
+        wildcardDirectories?: ts.MapLike<ts.WatchDirectoryFlags>;
         compilerOptions?: ts.CompilerOptions;
     }
 
@@ -391,7 +391,7 @@ namespace ts.server {
         // Used to keep track of what directories are watched for this project
         directoriesWatchedForTsconfig: string[] = [];
         program: ts.Program;
-        filenameToSourceFile: ts.Map<ts.SourceFile> = {};
+        filenameToSourceFile = ts.createMap<ts.SourceFile>();
         updateGraphSeq = 0;
         /** Used for configured projects which may have multiple open roots */
         openRefCount = 0;
@@ -504,7 +504,7 @@ namespace ts.server {
                 return;
             }
 
-            this.filenameToSourceFile = {};
+            this.filenameToSourceFile = createMap<SourceFile>();
             const sourceFiles = this.program.getSourceFiles();
             for (let i = 0, len = sourceFiles.length; i < len; i++) {
                 const normFilename = ts.normalizePath(sourceFiles[i].fileName);
@@ -613,7 +613,7 @@ namespace ts.server {
     }
 
     export class ProjectService {
-        filenameToScriptInfo: ts.Map<ScriptInfo> = {};
+        filenameToScriptInfo = ts.createMap<ScriptInfo>();
         // open, non-configured root files
         openFileRoots: ScriptInfo[] = [];
         // projects built from openFileRoots
@@ -625,12 +625,12 @@ namespace ts.server {
         // open files that are roots of a configured project
         openFileRootsConfigured: ScriptInfo[] = [];
         // a path to directory watcher map that detects added tsconfig files
-        directoryWatchersForTsconfig: ts.Map<FileWatcher> = {};
+        directoryWatchersForTsconfig = ts.createMap<FileWatcher>();
         // count of how many projects are using the directory watcher. If the
         // number becomes 0 for a watcher, then we should close it.
-        directoryWatchersRefCount: ts.Map<number> = {};
+        directoryWatchersRefCount = ts.createMap<number>();
         hostConfiguration: HostConfiguration;
-        timerForDetectingProjectFileListChanges: Map<any> = {};
+        timerForDetectingProjectFileListChanges = createMap<any>();
 
         constructor(public host: ServerHost, public psLogger: Logger, public eventHandler?: ProjectServiceEventHandler) {
             // ts.disableIncrementalParsing = true;

src/server/session.ts

@@ -1061,7 +1061,7 @@ namespace ts.server {
             return { response, responseRequired: true };
         }
 
-        private handlers: Map<(request: protocol.Request) => { response?: any, responseRequired?: boolean }> = {
+        private handlers: MapLike<(request: protocol.Request) => { response?: any, responseRequired?: boolean }> = {
             [CommandNames.Exit]: () => {
                 this.exit();
                 return { responseRequired: false };