astro/packages/markdown/remark/src/frontmatter-injection.ts
Ben Holmes e2019be6ff
Change frontmatter injection ordering (#5687)
* feat: make user frontmatter accessible in md

* test: new frontmatter injection

* refactor: move injection utils to remark pkg

* fix: add dist/internal to remark exports

* feat: update frontmater injection in mdx

* tests: new mdx injection

* chore: changeset

* chore: simplify frontmatter destructuring

* fix: remove old _internal references

* refactor: injectedFrontmatter -> remarkPluginFrontmatter

* docs: add content collections change

* chore: changeset heading levels
2023-01-03 16:31:19 -05:00

41 lines
1 KiB
TypeScript

import type { Data, VFile } from 'vfile';
import type { MarkdownAstroData } from './types.js';
function isValidAstroData(obj: unknown): obj is MarkdownAstroData {
if (typeof obj === 'object' && obj !== null && obj.hasOwnProperty('frontmatter')) {
const { frontmatter } = obj as any;
try {
// ensure frontmatter is JSON-serializable
JSON.stringify(frontmatter);
} catch {
return false;
}
return typeof frontmatter === 'object' && frontmatter !== null;
}
return false;
}
export class InvalidAstroDataError extends TypeError {}
export function safelyGetAstroData(vfileData: Data): MarkdownAstroData | InvalidAstroDataError {
const { astro } = vfileData;
if (!astro || !isValidAstroData(astro)) {
return new InvalidAstroDataError();
}
return astro;
}
export function toRemarkInitializeAstroData({
userFrontmatter,
}: {
userFrontmatter: Record<string, any>;
}) {
return () =>
function (tree: any, vfile: VFile) {
if (!vfile.data.astro) {
vfile.data.astro = { frontmatter: userFrontmatter };
}
};
}