Warn if compat date < most recent compat date supported by installed Wrangler

[irvinebroque]

We don't currently warn you at all if you're using an older compat date than what is supported by the version of Wrangler that you're running.

I think we should, because:

1. Most compat date updates simply mean things get better, a bug gets fixed, a new API is supported, etc.
2. There are a lot of projects out there that, unless they update their compat date to a more recent one, won't be able to use improved Node.js compat
3. Not everyone is familiar with compatibility dates, and if you gloss past them, you don't realize that being on a very old compat date is kind of like (though for important reasons not the same as) being on an old version of Node.js

If you look at an issue like cloudflare/next-on-pages#908 — people get mixed up despite guidance. And the more that we're loud about — update your compatibility date — we make sure that this is one of the first things that people experiment when trying to get something to work. We're going to get higher signal bug reports if people report "yes I've tried this with the latest compat date" versus us asking people to do this and circle back.

Maybe this is a bit aggressive, showing this every time you run wrangler dev. I could see possibly:

1. Only warning if your compat date is > n months older than the currently installed version of Wrangler
2. Allowing people to suppress the warning (do we have a mechanism for this?)

Finally — we should link to the relevant docs in the warning. One of the most consistent pieces of feedback I've heard talking to people is, "I wish you linked to that docs page you just sent me in the error message I got.".

[changeset-bot]

🦋 Changeset detected

Latest commit: 3d49dfc

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 4 packages

Name	Type
miniflare	Patch
wrangler	Patch
@cloudflare/pages-shared	Patch
@cloudflare/vitest-pool-workers	Patch

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[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-wrangler-7640

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npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/7640/npm-package-wrangler-7640

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npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-wrangler-7640 dev path/to/script.js

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wget https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-workers-bindings-extension-7640 -O ./cloudflare-workers-bindings-extension.0.0.0-v1ecabc81f.vsix && code --install-extension ./cloudflare-workers-bindings-extension.0.0.0-v1ecabc81f.vsix

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-create-cloudflare-7640 --no-auto-update

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-kv-asset-handler-7640

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-miniflare-7640

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-pages-shared-7640

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-unenv-preset-7640

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-vitest-pool-workers-7640

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-workers-editor-shared-7640

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-workers-shared-7640

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/12518514900/npm-package-cloudflare-workflows-shared-7640

Note that these links will no longer work once the GitHub Actions artifact expires.

---

[email protected] includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	3.20241218.0
workerd	1.20241218.0	1.20241218.0
workerd --version	1.20241218.0	2024-12-18

Please ensure constraints are pinned, and miniflare/workerd minor versions match.