addons/docs/src/blocks/Meta.tsx
import React, { FC, useContext } from 'react';
import global from 'global';
import { BaseAnnotations } from '@storybook/csf';
import { Anchor } from './Anchor';
import { DocsContext, DocsContextProps } from './DocsContext';
const { document } = global;
type MetaProps = BaseAnnotations;
function getFirstStoryId(docsContext: DocsContextProps): string {
const stories = docsContext.componentStories();
return stories.length > 0 ? stories[0].id : null;
}
function renderAnchor() {
const context = useContext(DocsContext);
const anchorId = getFirstStoryId(context) || context.id;
return <Anchor storyId={anchorId} />;
}
/**
* This component is used to declare component metadata in docs
* and gets transformed into a default export underneath the hood.
*/
export const Meta: FC<MetaProps> = () => {
const params = new URL(document.location).searchParams;
const isDocs = params.get('viewMode') === 'docs';
return isDocs ? renderAnchor() : null;
};