Dependencies: Deduplicate @wordpress/ packages

[ockham]

Follow-up to #16845 (comment), where @jsnajdr suggested de-duplicating dependencies in yarn.lock, which had been blocking #16845.

Changes proposed in this Pull Request:

Deduplicate dependencies in yarn.lock by using yarn-deduplicate

npx yarn-deduplicate --scopes @wordpress

This is the first time I'm using this, hope I'm doing it right 🤞

Jetpack product discussion

N/A

Does this pull request change what data or activity we track or use?

No

Testing instructions:

Verify that things still work as before (check CI, do sufficient smoke testing).

Proposed changelog entry for your changes:

Deduplicate @wordpress/ dependencies

[matticbot]

Caution: This PR has changes that must be merged to WordPress.com
Hello ockham! These changes need to be synced to WordPress.com - If you 're an a11n, please commandeer and confirm D51560-code works as expected before merging this PR. Once this PR is merged, please commit the changes to WP.com. Thank you!
This revision will be updated with each commit to this PR

[ockham]

Hold on, I'll try just deduplicating @wordpress/ packages for now...

[jetpackbot]

Scheduled Jetpack release: November 10, 2020.
Scheduled code freeze: November 3, 2020

E2E results is available here (for debugging purposes): https://jetpack-e2e-dashboard.herokuapp.com/pr-17559

Thank you for the great PR description!

When this PR is ready for review, please apply the [Status] Needs Review label. If you are an a11n, please have someone from your team review the code if possible. The Jetpack team will also review this PR and merge it to be included in the next Jetpack release.

Generated by 🚫 dangerJS against 346d5db

[jeherve]

This looks good. Let's merge it right now so it gets tested by everyone in the next few weeks.

How can we ensure that duplications don't happen again next time we update packages?

[kraftbj]

r215724-wpcom

[ockham]

This looks good. Let's merge it right now so it gets tested by everyone in the next few weeks.

How can we ensure that duplications don't happen again next time we update packages?

I'm not entirely sure TBH. @scinos might know 😄

[scinos]

How can we ensure that duplications don't happen again next time we update packages?

I'm not entirely sure TBH. @scinos might know 😄

AFAIK it is not possible. By design, yarn won't dedupe existing packages because technically is a risky operation (eg: some code path was getting lib@1.0.0 before and now it gets lib@1.0.1), which they don't want to do.

If we can achieve total deduplication then we could add a new CI job to run npx yarn-deduplicate --fail, which will fail if a new duplication is introduced. That will at least remind us to run yarn-deduplicate when we bump dependencies.

[jsnajdr]

How can we ensure that duplications don't happen again next time we update packages?

We plan to re-declare many dependencies in the Gutenberg monorepo as peer dependencies: WordPress/gutenberg#8981 (comment) The proposal was discussed in a core-js chat this week and will most likely be implemented.

That doesn't solve everything, but will prevent yarn/npm from installing duplicate packages where it's obviously undesired, and will make them issue a warning instead.