Core: Ensure we don't reset WebPreview if calling start() in v7 mode

[tmeasday]

Issue: #16455

The problem was that when you import from @storybook/angular it calls start() (as do all other frameworks), which created an old, non-v7 StoryStore and assigned it to __STORYBOOK_STORY_STORE__, then awaited a configure() call (that never came....)

What I did

• Ensure start() is a no-op in v7 mode
• Return an API that throws errors

Questions

Should we make some of that API work (i.e. api.raw() etc?)

How to test

See example in issue.

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[shilman]

Sorry, I'm missing how this is connected to the bug.

1. I don't see any imports from @storybook/angular in his code
2. Is this the line that's ultimately failing?

https://github.com/storybookjs/storybook/blob/next/addons/a11y/src/a11yRunner.ts#L72

[tmeasday]

I don't see any imports from @storybook/angular in his code

https://github.com/literalpie/sb-ng-performance/blob/f6539c5fbe7338a71a437c4514e89b6cef314b2b/src/stories/Header.stories.ts#L1

Is this the line that's ultimately failing?

Yeah, correct. The second story store that is created is never initialized (as configure() is never called) and so loadStory() hangs forever waiting on the initializationPromise.

[shilman]

Thanks for the clarification @tmeasday. Fixed a couple bugs with the API signature 😉