Storybook CSF factory .extend() enrichment repro

Minimal reproduction for a bug in Storybook 10.4.1 where stories created with .extend() are not recognised as CSF factory stories by enrichCsfStory.

Steps to reproduce

yarn install
yarn storybook
# Open http://localhost:6006/?path=/docs/mybutton--secondary

Expected

Both the Primary and Secondary stories display their JSDoc descriptions and "Show code" source in the docs panel.

Actual

Primary (created with meta.story()) shows its description and source correctly. Secondary (created with Primary.extend()) shows neither.

Root cause

enrichCsfStory in dist/_node-chunks/chunk-RYS45SZ5.js determines whether a story is a CSF factory story using this check:

isCsfFactory =
  t5.isCallExpression(storyExport) &&
  t5.isMemberExpression(storyExport.callee) &&
  t5.isIdentifier(storyExport.callee.object) &&
  storyExport.callee.object.name === "meta"

This matches meta.story(…) calls but not .extend() calls, because for Primary.extend(…) the callee object is Primary, not meta.

When isCsfFactory is false, the enrichment writes docs parameters to Secondary.parameters instead of Secondary.input.parameters. At runtime, Storybook reads from story.input.parameters.docs, so the enriched data is never found.

This is visible in the compiled output (storybook-static/assets/my-button.stories-*.js):

// Primary — correct: written to .input.parameters
t.input.parameters = { ...t.input.parameters, docs: { source: {…}, description: {…} } }

// Secondary — wrong: written to .parameters, not .input.parameters
o.parameters = { ...o.parameters, docs: { source: {…}, description: {…} } }

Suggested fix

Extend the isCsfFactory check to also match .extend() calls:

isCsfFactory =
  t5.isCallExpression(storyExport) &&
  t5.isMemberExpression(storyExport.callee) &&
  (
    (t5.isIdentifier(storyExport.callee.object) && storyExport.callee.object.name === "meta") ||
    (t5.isIdentifier(storyExport.callee.property) && storyExport.callee.property.name === "extend")
  )