Add comment and test to enforce the name of the tutorial database

I'm extracting the call to `openDatabase` where we set a custom display name
into a separate method: `openTutorialDatabase`.

I've added comments to it to specify the display name is significant.

I've also added a test that will fail if you ever change the name of the
tutorial database.

Author: elenatanasoiu

extensions/ql-vscode/src/local-databases-ui.ts

@@ -380,12 +380,7 @@ export class DatabaseUI extends DisposableObject {
 
         let databaseItem = this.databaseManager.findDatabaseItem(uri);
         if (databaseItem === undefined) {
-          databaseItem = await this.databaseManager.openDatabase(
-            progress,
-            token,
-            uri,
-            "CodeQL Tutorial Database",
-          );
+          databaseItem = await this.openTutorialDatabase(progress, token, uri);
         }
         await this.databaseManager.setCurrentDatabaseItem(databaseItem);
       }
@@ -399,6 +394,22 @@ export class DatabaseUI extends DisposableObject {
     }
   };
 
+  // Opens the tutorial database for the CodeQL Tour.
+  // We set the database name as "CodeQL Tutorial Database" in purpose. This means
+  // we won't attempt to create a skeleton QL pack for this database.
+  openTutorialDatabase = async (
+    progress: ProgressCallback,
+    token: CancellationToken,
+    uri: Uri,
+  ): Promise<DatabaseItem> => {
+    return await this.databaseManager.openDatabase(
+      progress,
+      token,
+      uri,
+      "CodeQL Tutorial Database",
+    );
+  };
+
   handleRemoveOrphanedDatabases = async (): Promise<void> => {
     void extLogger.log("Removing orphaned databases from workspace storage.");
     let dbDirs = undefined;

extensions/ql-vscode/test/vscode-tests/no-workspace/local-databases-ui.test.ts

@@ -7,12 +7,14 @@ import {
   createFileSync,
   pathExistsSync,
 } from "fs-extra";
-import { Uri } from "vscode";
+import { CancellationToken, Uri } from "vscode";
 
 import { DatabaseUI } from "../../../src/local-databases-ui";
 import { testDisposeHandler } from "../test-dispose-handler";
 import { createMockApp } from "../../__mocks__/appMock";
 import { QueryLanguage } from "../../../src/common/query-language";
+import { App } from "../../../src/common/app";
+import { ProgressCallback } from "../../../src/commandRunner";
 
 describe("local-databases-ui", () => {
   describe("fixDbUri", () => {
@@ -116,6 +118,51 @@ describe("local-databases-ui", () => {
     databaseUI.dispose(testDisposeHandler);
   });
 
+  describe("openTutorialDatabase", () => {
+    let app: App;
+    let databaseUI: DatabaseUI;
+    let openDatabaseSpy: jest.SpyInstance;
+    let databaseManager: any;
+
+    beforeEach(async () => {
+      app = createMockApp({});
+      openDatabaseSpy = jest.fn();
+
+      databaseManager = {
+        databaseItems: [],
+        openDatabase: openDatabaseSpy,
+        onDidChangeDatabaseItem: () => {
+          /**/
+        },
+        onDidChangeCurrentDatabaseItem: () => {
+          /**/
+        },
+      };
+      databaseUI = new DatabaseUI(
+        app,
+        databaseManager as any,
+        {} as any,
+        "",
+        "",
+      );
+    });
+
+    it("should call openDatase with 'CodeQL Tutorial Database' as displayName", async () => {
+      await databaseUI.openTutorialDatabase(
+        {} as ProgressCallback,
+        {} as CancellationToken,
+        Uri.parse(""),
+      );
+
+      expect(openDatabaseSpy).toHaveBeenCalledWith(
+        expect.anything(),
+        expect.anything(),
+        expect.anything(),
+        "CodeQL Tutorial Database",
+      );
+    });
+  });
+
   function createDatabase(
     storageDir: string,
     dbName: string,