Build: Automatically recompile on branch switch

[Sidnioulz]

What I did

Added an optional Git hook on checkout to reinstall deps and recompile the codebase. Ensures you're ready to use the branch without manual intervention.

Gated by STORYBOOK_COMPILE_ON_CHECKOUT env.

Checklist for Contributors

Testing

Manual testing

• Checkout this branch
• git checkout -b dummy-branch and notice no compilation
• export STORYBOOK_COMPILE_ON_CHECKOUT=true
• git checkout -b dummier-branch and notice that SB now reinstalls deps and recompiles

Checklist for Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli-storybook/src/sandbox-templates.ts

• Make sure this PR contains one of the labels below:

  Available labels

  • bug: Internal changes that fixes incorrect behavior.
  • maintenance: User-facing maintenance tasks.
  • dependencies: Upgrading (sometimes downgrading) dependencies.
  • build: Internal-facing build tooling & test updates. Will not show up in release changelog.
  • cleanup: Minor cleanup style change. Will not show up in release changelog.
  • documentation: Documentation only changes. Will not show up in release changelog.
  • feature request: Introducing a new feature.
  • BREAKING CHANGE: Changes that break compatibility in some way with current major version.
  • other: Changes that don't fit in the above categories.

🦋 Canary release

This PR does not have a canary release associated. You can request a canary release of this pull request by mentioning the @storybookjs/core team here.

core team members can create a canary release here or locally with gh workflow run --repo storybookjs/storybook publish.yml --field pr=<PR_NUMBER>

Summary by CodeRabbit

• Chores
  • Added optional automatic Storybook compilation when switching branches, controllable via an environment setting to keep build artifacts synchronized.
  • Exposed an additional manager error to improve error reporting and surface clearer failure information in the UI.

[Copilot]

Pull request overview

Adds an optional Husky post-checkout Git hook that can reinstall dependencies and recompile the repo when switching branches, gated by STORYBOOK_COMPILE_ON_CHECKOUT.

Changes:

• Introduces .husky/post-checkout to run yarn and yarn task compile -s compile when STORYBOOK_COMPILE_ON_CHECKOUT is set.

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: ab134657-fce5-4c9c-acdc-944cbc0bf2a5

📥 Commits

Reviewing files that changed from the base of the PR and between 54f6b4d and ead5b73.

📒 Files selected for processing (1)

• .husky/post-checkout

🚧 Files skipped from review as they are similar to previous changes (1)

• .husky/post-checkout

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📝 Walkthrough

Walkthrough

Adds a conditional Git post-checkout hook .husky/post-checkout that runs yarn and yarn task compile -s compile when STORYBOOK_COMPILE_ON_CHECKOUT is "true", and adds UniversalStoreFollowerTimeoutError to the manager global exports list.

Changes

Post-checkout hook

Layer / File(s)	Summary
Post-checkout hook configuration .husky/post-checkout	Adds a post-checkout Git hook that checks STORYBOOK_COMPILE_ON_CHECKOUT for the exact value "true", then runs yarn and yarn task compile -s compile.

Manager globals export

Layer / File(s)	Summary
Add UniversalStoreFollowerTimeoutError export code/core/src/manager/globals/exports.ts	Adds UniversalStoreFollowerTimeoutError to the storybook/internal/manager-errors entry in the globalized export list.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• storybookjs/storybook#34126: Related Husky/hooks changes affecting how and when .husky/* hooks are installed and run.

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In @.husky/post-checkout:
- Around line 1-2: The post-checkout hook currently uses a non-empty check for
STORYBOOK_COMPILE_ON_CHECKOUT which treats any non-empty value (including
"false") as true; change the if condition in .husky/post-checkout to an explicit
boolean comparison such as [ "$STORYBOOK_COMPILE_ON_CHECKOUT" = "true" ] (or
check for "1" as an alternative) so yarn && yarn task compile -s compile only
runs when the variable is intentionally enabled.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 5f23ef26-d3be-427e-b306-cb88665d4112

📥 Commits

Reviewing files that changed from the base of the PR and between 73fa773 and 394ef59.

📒 Files selected for processing (1)

• .husky/post-checkout