Improve scene type visibility

libs/playwright-helpers/src/play.ts

@@ -24,8 +24,10 @@ export class Play {
    * @param options Options for the scene
    * @returns
    */
-  static async scene<TUp, TResult>(template: SceneTemplate<TUp, TResult>): Promise<Scene<TResult>> {
-    const scene = new Scene<TResult>();
+  static async scene<TUp, TResult>(
+    template: SceneTemplate<TUp, TResult>,
+  ): Promise<Scene<TUp, TResult>> {
+    const scene = new Scene<TUp, TResult>();
     await scene.init(template);
     return scene;
   }

libs/playwright-helpers/src/scene-templates/scene-template.ts

@@ -3,6 +3,8 @@ import { webServerBaseUrl } from "@playwright-config";
 // First seed points at the seeder API proxy, second is the seed path of the SeedController
 const seedApiUrl = new URL("/seed/seed/", webServerBaseUrl).toString();
 
+export type extractTUpType<T> = T extends SceneTemplate<infer U, any> ? U : never;
+
 export abstract class SceneTemplate<TUp, TReturns = void> {
   abstract template: string;
   private seedId?: string;
@@ -14,7 +16,7 @@ export abstract class SceneTemplate<TUp, TReturns = void> {
     return this.seedId;
   }
 
-  constructor(private upArgs: TUp) {}
+  constructor(public upArgs: TUp) {}
   async up(): Promise<SceneTemplateResult<TReturns>> {
     const result = await sceneUp<TUp, TReturns>(this.template, this.upArgs);
     this.seedId = result.seedId;

libs/playwright-helpers/src/scene-templates/single-user.scene.ts

@@ -5,16 +5,14 @@ import { Scene } from "../scene";
 import { SceneTemplate } from "./scene-template";
 
 type SceneResult = UserId;
+type UpParams = {
+  email: string;
+  emailVerified?: boolean;
+  premium?: boolean;
+};
 
-export type SingleUserScene = Scene<SceneResult>;
+export type SingleUserScene = Scene<UpParams, SceneResult>;
 
-export class SingleUserSceneTemplate extends SceneTemplate<
-  {
-    email: string;
-    emailVerified?: boolean;
-    premium?: boolean;
-  },
-  SceneResult
-> {
+export class SingleUserSceneTemplate extends SceneTemplate<UpParams, SceneResult> {
   template: string = "SingleUserScene";
 }

libs/playwright-helpers/src/scene.ts

@@ -10,15 +10,15 @@ import { SceneTemplate } from "./scene-templates/scene-template";
  * - {@link SceneOptions.noDown}: Useful for setting up data then using codegen to create tests that use the data. Remember to tear down the data manually.
  * - {@link SceneOptions.downAfterAll}: Useful for expensive setups that you want to share across all tests in a worker or for writing acts.
  */
-export class Scene<Returns = void> {
+export class Scene<UpParams = unknown, Returns = void> {
   private inited = false;
-  private _template?: SceneTemplate<unknown, Returns>;
+  private _template?: SceneTemplate<UpParams, Returns>;
   private mangledMap = new Map<string, string | null>();
   private _returnValue?: Returns;
 
   constructor() {}
 
-  private get template(): SceneTemplate<unknown, Returns> {
+  private get template(): SceneTemplate<UpParams, Returns> {
     if (!this.inited) {
       throw new Error("Scene must be initialized before accessing template");
     }
@@ -28,6 +28,10 @@ export class Scene<Returns = void> {
     return this._template;
   }
 
+  get upArgs(): UpParams {
+    return this.template.upArgs;
+  }
+
   get returnValue(): Returns {
     if (!this.inited) {
       throw new Error("Scene must be initialized before accessing returnValue");
@@ -43,7 +47,7 @@ export class Scene<Returns = void> {
     return this.mangledMap.get(id) ?? id;
   }
 
-  async init<T extends SceneTemplate<TUp, Returns>, TUp>(template: T): Promise<void> {
+  async init(template: SceneTemplate<UpParams, Returns>): Promise<void> {
     if (this.inited) {
       throw new Error("Scene has already been initialized");
     }