fix: allow override NextraConfig.mdxOptions.format option in next.config file (#4373)

Author: dimaMachina

.changeset/light-walls-end.md

@@ -0,0 +1,5 @@
+---
+"nextra": patch
+---
+
+fix: allow override `NextraConfig.mdxOptions.format` option in `next.config` file

packages/nextra/src/server/loader.ts

@@ -132,7 +132,6 @@ export async function loader(
       ...mdxOptions,
       jsx: true,
       outputFormat: 'program',
-      format: 'detect',
       rehypePrettyCodeOptions: {
         ...mdxOptions.rehypePrettyCodeOptions,
         transformers: [

packages/nextra/src/server/schemas.ts

@@ -52,7 +52,7 @@ export const nextraConfigSchema = z.strictObject({
       rehypePlugins: z.custom<ProcessorOptions['rehypePlugins']>(),
       remarkPlugins: z.custom<ProcessorOptions['remarkPlugins']>(),
       recmaPlugins: z.custom<ProcessorOptions['recmaPlugins']>(),
-      format: z.enum(['detect', 'mdx', 'md']).optional(),
+      format: z.enum(['detect', 'mdx', 'md']).default('detect'),
       rehypePrettyCodeOptions: z.custom<RehypePrettyCodeOptions>().default({})
     })
     .default({}),