6.4 makeDecorator: storyFn requires 2 parametors?

[NickMcBurney]

I have a decorator using syntax as described here: https://storybook.js.org/docs/vue/addons/addons-api#makedecorator-api

But with Storybook 6.4 I'm getting build errors because storyFn is expecting 2 arguments:

wrapper: (storyFn: StoryFn, context: StoryContext) => {
  /* ... some code ... */

  return storyFn(context); // this line errors 'Expected 2 arguments, but got 1.ts(2554)'
}

I can't find any guidance on this in docs, and the TS definitions aren't very helpful.

Does anyone know what storyFn is expecting as 2nd argument?

[shilman]

@NickMcBurney what version are you upgrading from? starting in 6.0, story functions take an args object as their first input, and the context object as their second https://storybook.js.org/blog/introducing-storybook-args/

[NickMcBurney]

Hi @tmeasday, sorry for that, tbh I could see the issue without build so thought that was OK. Here is GIT repo to my branch with the update:
https://github.com/NickMcBurney/storybook-vue3-router/tree/storybook-6.4.x

[tmeasday]

Ahhh, OK. There was a type problem in your original code, this line:

    wrapper: (storyFn: StoryFn, context: StoryContext) => {

Should be

    wrapper: (storyFn: LegacyStoryFn, context: StoryContext) => {

But it didn't complain in 6.3 as the type of ArgStoryFn (the other "half" of StoryFn) was overly permissive.

[NickMcBurney]

@tmeasday thanks that sorted it now.

[tmeasday]

@NickMcBurney just to check, you didn't copy that line from anywhere in the docs that we should fix? (Fair enough if you don't recall :) )

[NickMcBurney]

@tmeasday I'm pretty sure I cobbled this together myself and didn't copy from docs. Think its entirely my own fault 🤣