feat: expose id to frontmatterPreprocess

Author: antfu

src/markdown.ts

@@ -118,7 +118,7 @@ export function createMarkdown(options: ResolvedOptions) {
         data.excerpt = excerpt
       }
 
-      const { head, frontmatter } = frontmatterPreprocess(data || {}, options, preprocessHead)
+      const { head, frontmatter } = frontmatterPreprocess(data || {}, options, id, preprocessHead)
 
       if (options.excerpt && !excerptKeyOverlapping && frontmatter.excerpt !== undefined)
         delete frontmatter.excerpt

src/options.ts

@@ -23,7 +23,7 @@ export function resolveOptions(userOptions: Options): ResolvedOptions {
     wrapperClasses: 'markdown-body',
     include: null,
     exclude: null,
-    frontmatterPreprocess: (frontmatter, options, defaults) => {
+    frontmatterPreprocess: (frontmatter, options, _id, defaults) => {
       return {
         head: defaults(frontmatter, options),
         frontmatter,

src/types.ts

@@ -108,6 +108,7 @@ export interface Options {
   frontmatterPreprocess?: (
     frontmatter: Frontmatter,
     options: ResolvedOptions,
+    id: string,
     defaultHeadProcess: typeof preprocessHead,
   ) => {
     head: Record<string, any>