Fix md document links for untitled files (microsoft#155248)

Author: mjbvz

extensions/markdown-language-features/server/src/workspace.ts

@@ -162,7 +162,10 @@ export class VsCodeClientWorkspace implements md.IWorkspace {
 		}
 	}
 
-	stat(resource: URI): Promise<md.FileStat | undefined> {
+	async stat(resource: URI): Promise<md.FileStat | undefined> {
+		if (this._documentCache.has(resource) || this.documents.get(resource.toString())) {
+			return { isDirectory: false };
+		}
 		return this.connection.sendRequest(protocol.statFileRequestType, { uri: resource.toString() });
 	}
 

extensions/markdown-language-features/src/test/documentLink.test.ts

@@ -134,7 +134,7 @@ async function getLinksForFile(file: vscode.Uri): Promise<vscode.DocumentLink[]>
 		}
 	});
 
-	test.skip('Should navigate to fragment within current untitled file', async () => { // TODO: skip for now for ls migration
+	test('Should navigate to fragment within current untitled file', async () => { // TODO: skip for now for ls migration
 		const testFile = workspaceFile('x.md').with({ scheme: 'untitled' });
 		await withFileContents(testFile, joinLines(
 			'[](#second)',