Addon-docs: Support subcomponents as a top-level default export

[shilman]

Issue: #7811

What I did

Support export default { title, component, subcomponents } in addition to export default { title, component, parameters: { subcomponents }} to match the documentation. Also added a test case.

[vercel]

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[tmeasday]

WFM

[adeelibr]

is this still only available in beta version? 😄 @shilman
P.S: thank you for adding this wonderful feature. :)

[shilman]

@adeelibr 5.3 is in RC now, with full release targeted for early Jan

[aareman]

This doesn't work for me.
"@storybook/react": "^5.3.0-rc.0",

export default {
    title: 'Demos|Layouts',
    component: Container,
    subcomponents: { Tabs, Tab },
};

I tried this as well

export default {
    title: 'Demos|Layouts',
    component: Container,
    subcomponents: [ Tabs, Tab ],
};

[adeelibr]

Works at my end. @aareman

[aareman]

@adeelibr silly me. I had the beta for storybook not the docs. :) let that be a lesson to the next guy like me.

Thank you. Really awesome stuff!