Would like to understand what's the reason for @storybook/test to have testing-library pkgs built-in

[csantos1113]

I'm trying to move away from https://github.com/storybookjs/testing-library to https://github.com/storybookjs/storybook/blob/v7.6.19/code/lib/test (I'm not ready to go up to 8.x)

And I thought it was going to be just find and replace; but it doesn't seem to be the case.

I've a lot of unit tests throwing act() warnings like:

Triage

• I have cloned https://github.com/storybookjs/storybook/blob/v7.6.19
• I've built the packages locally
• and, after a lot of try and catch I narrowed the issue down to the following lines:

storybook/code/lib/test/package.json

Lines 71 to 74 in 0264a14

	"noExternal": [
	"@testing-library/dom",
	"@testing-library/jest-dom",
	"@testing-library/user-event",

the act() warnings go away once I removed those 3 lines, built the package, and use that package.

Why I think this is happening?

I believe this is because the version of @testing-library/xxx I have installed are different to the ones that are baked into @storybook/test dist folder.

noExternal prop

None of other storybook packages use this feature of baking dependencies into it. I wonder why @storybook/test is the exception?

I see it was added in f42e9ef by @kasperpeulen but I've no clue as why

Note: I see that list still exists in next

storybook/code/lib/test/package.json

Lines 71 to 74 in fdadc41

	"noExternal": [
	"@testing-library/dom",
	"@testing-library/jest-dom",
	"@testing-library/user-event",

- but I don't think it matters for my use case

---

Appreciate any help 🙏

[kasperpeulen]

cc @yannbf You also had this problem with act warnings right?

@csantos1113 We pre-bundle those packages for performance reasons. I will invrestigate what causes the act difference when prebundling.

[csantos1113]

Hey guys, I wonder if we should convert this to issue?

Thank you!

[kasperpeulen]

I think this issue is similar, and will be fixed in 8.2:
#27173

Also going to be patched back to 8.1.

BTW, upgrading to 8 doesn't require changes for lots of storybooks.
I think the main breaking change is if you use spies in play functions, which need to be explicit now.