Merged PR 468200: Tell Roslyn to initialize Razor only when the user …

…needs to

Allows the extension to be in charge of when the Roslyn does its work to initialize Razor.

The Roslyn side of this, which handles the notification, is https://dnceng.visualstudio.com/internal/_git/dotnet-roslyn/pullrequest/30922

Also related is dotnet/razor#8639

src/lsptoolshost/roslynLanguageServer.ts

@@ -64,6 +64,7 @@ export class RoslynLanguageServer {
     public static readonly roslynPullDiagnosticCommand: string = 'roslyn.pullDiagnosticRazorCSharp';
     public static readonly provideCodeActionsCommand: string = 'roslyn.provideCodeActions';
     public static readonly resolveCodeActionCommand: string = 'roslyn.resolveCodeAction';
+    public static readonly razorInitializeCommand: string = 'razor.initialize';
 
     // These are notifications we will get from the LSP server and will forward to the Razor extension.
     private static readonly provideRazorDynamicFileInfoMethodName: string = 'razor/provideDynamicFileInfo';
@@ -386,6 +387,13 @@ export class RoslynLanguageServer {
         vscode.commands.registerCommand(RoslynLanguageServer.resolveCodeActionCommand, async (request: CodeAction) => {
             return await this.sendRequest(CodeActionResolveRequest.type, request, CancellationToken.None);
         });
+
+        // Roslyn is responsible for producing a json file containing information for Razor, that comes from the compilation for
+        // a project. We want to defer this work until necessary, so this command is called by the Razor document manager to tell
+        // us when they need us to initialize the Razor things.
+        vscode.commands.registerCommand(RoslynLanguageServer.razorInitializeCommand, () => {
+            client.sendNotification("razor/initialize", { });
+        });
     }
 
     private getServerFileName() {

src/razor/src/Document/RazorDocumentManager.ts

@@ -28,6 +28,7 @@ import { createDocument } from './RazorDocumentFactory';
 
 export class RazorDocumentManager implements IRazorDocumentManager {
     public roslynActivated = false;
+    public razorDocumentGenerationInitialized = false;
 
     private readonly razorDocuments: { [hostDocumentPath: string]: IRazorDocument } = {};
     private readonly openRazorDocuments = new Set<string>();
@@ -56,8 +57,6 @@ export class RazorDocumentManager implements IRazorDocumentManager {
     public async getDocument(uri: vscode.Uri) {
         const document = this._getDocument(uri);
 
-        await this.ensureDocumentAndProjectedDocumentsOpen(document);
-
         return document;
     }
 
@@ -111,7 +110,7 @@ export class RazorDocumentManager implements IRazorDocumentManager {
                 continue;
             }
 
-            this.openDocument(textDocument.uri);
+            await this.openDocument(textDocument.uri);
         }
     }
 
@@ -122,12 +121,12 @@ export class RazorDocumentManager implements IRazorDocumentManager {
             async (uri: vscode.Uri) => this.addDocument(uri));
         const didDeleteRegistration = watcher.onDidDelete(
             async (uri: vscode.Uri) => this.removeDocument(uri));
-        const didOpenRegistration = vscode.workspace.onDidOpenTextDocument(document => {
+        const didOpenRegistration = vscode.workspace.onDidOpenTextDocument(async document => {
             if (document.languageId !== RazorLanguage.id) {
                 return;
             }
 
-            this.openDocument(document.uri);
+            await this.openDocument(document.uri);
         });
         const didCloseRegistration = vscode.workspace.onDidCloseTextDocument(document => {
             if (document.languageId !== RazorLanguage.id) {
@@ -165,7 +164,20 @@ export class RazorDocumentManager implements IRazorDocumentManager {
         return document;
     }
 
-    private openDocument(uri: vscode.Uri) {
+    private async openDocument(uri: vscode.Uri) {
+        // On first open of a Razor document, we kick off the generation of all razor documents so that
+        // components are discovered correctly. If we do this early, when we initialize everything, we
+        // just spend a lot of time generating documents and json files that might not be needed.
+        // If we wait for each individual document to be opened by the user, then locally defined components
+        // don't work, which is a poor experience. This is the compromise.
+        if (!this.razorDocumentGenerationInitialized) {
+            this.razorDocumentGenerationInitialized = true;
+            vscode.commands.executeCommand(RoslynLanguageServer.razorInitializeCommand);
+            for (const document of this.documents) {
+                await this.ensureDocumentAndProjectedDocumentsOpen(document);
+            }
+        }
+
         const document = this._getDocument(uri);
 
         this.notifyDocumentChange(document, RazorDocumentChangeKind.opened);