Csf-tools: Fix local vars handling in MDX-generated CSF

code/lib/csf-tools/src/CsfFile.test.ts

@@ -378,6 +378,36 @@ describe('CsfFile', () => {
       `);
     });
 
+    it('docs-only story with local vars', () => {
+      expect(
+        parse(
+          dedent`
+            export const TestControl = () => _jsx("p", {
+              children: "Hello"
+            });
+            export default { title: 'foo/bar', tags: ['mdx'], includeStories: ["__page"] };
+            export const __page = () => {};
+            __page.parameters = { docsOnly: true };
+          `,
+          true
+        )
+      ).toMatchInlineSnapshot(`
+        meta:
+          title: foo/bar
+          tags:
+            - mdx
+          includeStories:
+            - __page
+        stories:
+          - id: foo-bar--page
+            name: Page
+            parameters:
+              __isArgsStory: false
+              __id: foo-bar--page
+              docsOnly: true
+      `);
+    });
+
     it('title variable', () => {
       expect(
         parse(

code/lib/csf-tools/src/CsfFile.ts

@@ -458,7 +458,11 @@ export class CsfFile {
       if (isExportStory(key, self._meta)) {
         const id = toId(self._meta.id || self._meta.title, storyNameFromExport(key));
         const parameters: Record<string, any> = { ...story.parameters, __id: id };
-        if (entries.length === 1 && key === '__page') {
+        const { includeStories } = self._meta || {};
+        if (
+          key === '__page' &&
+          (entries.length === 1 || (Array.isArray(includeStories) && includeStories.length === 1))
+        ) {
           parameters.docsOnly = true;
         }
         acc[key] = { ...story, id, parameters };