Construct VirtualServerHost directly in tsserver

src/harness/virtualFileSystemWithWatch.ts

@@ -53,6 +53,14 @@ interface Array<T> { length: number; [n: number]: T; }`
         return host;
     }
 
+    export function createVirtualServerHost(params: VirtualServerHostCreationParameters): VirtualServerHost {
+        const host = new VirtualServerHost(params);
+        host.init();
+        // Just like sys, patch the host to use writeFile
+        patchWriteFileEnsuringDirectory(host);
+        return host;
+    }
+
     class Callbacks {
         private map: TimeOutCallback[] = [];
         private nextId = 1;

src/tsserver/server.ts

@@ -58,11 +58,18 @@ namespace ts.server {
         console.warn = (...args) => logger.msg(args.length === 1 ? args[0] : args.join(", "), Msg.Err);
         console.error = (...args) => logger.msg(args.length === 1 ? args[0] : args.join(", "), Msg.Err);
 
-        const fshost = vfs ? VirtualFS.createVirtualServerHost([], {
-            useCaseSensitiveFileNames: sys.useCaseSensitiveFileNames,
-            executingFilePath: "", // TODO: "" is the default..maybe this should be vfs, vfs:// or .
-            newLine: sys.newLine,
-        }) : sys as ServerHost;
+        let fshost
+        if (vfs) {
+            fshost = new VirtualFS.VirtualServerHost({
+                useCaseSensitiveFileNames: sys.useCaseSensitiveFileNames,
+                executingFilePath: "", // TODO: "" is the default..maybe this should be vfs, vfs:// or .
+                newLine: sys.newLine,
+            })
+            fshost.init()
+        }
+        else {
+            fshost = sys as ServerHost;
+        }
         startServer(
             {
                 globalPlugins: findArgumentStringArray("--globalPlugins"),

src/vfs/virtualFileSystemWithWatch.ts

@@ -8,14 +8,6 @@ namespace ts.VirtualFS {
         windowsStyleRoot?: string;
     }
 
-    export function createVirtualServerHost(params: VirtualServerHostCreationParameters): VirtualServerHost {
-        const host = new VirtualServerHost(params);
-        host.init();
-        // Just like sys, patch the host to use writeFile
-        patchWriteFileEnsuringDirectory(host);
-        return host;
-    }
-
     export interface File {
         path: string;
         content: string;