This is a small change to the image post-processor logic. When it's looking for images to preload, it will now ignore SVGs, as these are rarely the relevant images for LCP.
This pull request replaces our client-side style transitions with `<style>` tags over async `<link rel=stylesheet>` tags. This should fix some edge cases users see with Chrome accidentally causing a FOUC.
This also removes the need to perform an async operation before starting the render, which should remove any perceivable navigation delay.
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Fixes#16289
Handles:
- Next.js version
- next.config.js `env` key
- `NEXT_PUBLIC_` prefixed environment variables
- next.config.js keys that affect performance
Ideally we don't invalidate the whole cache when `NEXT_PUBLIC_` / `env` key variables change, but this is just to initially make the caching reliable, this behavior is similar to the current webpack 4 behavior, so it can only be improved 👍
When navigating from a non-shallow page to a page that was navigated to shallowly in history it causes incorrect page data to be shown since an incorrect shallow navigation is done. We can only maintain shallow routing when the current page was navigated to shallowly and the page being navigated to in history was also navigated to shallowly. Additional tests to ensure this behavior is working has also been added.
Closes: https://github.com/vercel/next.js/issues/7395
Closes: https://github.com/vercel/next.js/issues/14928
Fixes: https://github.com/vercel/next.js/issues/16028
This pull request correctly tracks render cancelation behavior. Prior to this PR, we'd have an unhandled rejection that left the app in a bad state and no routeChangeError event was fired.
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Closes#16424Fixes#16445
This makes sure to also check if a dynamic route matched after resolving a rewrite on the client to match behavior on the server. It also adds tests for this behavior to ensure it is working properly.
Fixes: https://github.com/vercel/next.js/issues/16454
This fixes a client-side file not being transpiled correctly when rewrites are used. The cross browser tests have been updated to make sure there are rewrites so the related code is included and not dead-code eliminated'
Closes: https://github.com/vercel/next.js/issues/16440
We were accidentally allowing data requests to be rendered unconditionally. Instead, we should also check them against the staticPaths result and 404 when appropriate.
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Fixes#15383
This fixes page checking failing due to the trailing slash being present which causes pages to proxied by a rewrite when they shouldn't be. This also adds additional tests to ensure rewriting to an external resource is working correctly with `trailingSlash: true`
Fixes: https://github.com/vercel/next.js/issues/15700
This corrects the basePath being required check for filesystem routes to not consider the public folder catch-all route since it always matches even if the public file isn't present and instead moves the basePath check inside of the public-folder catch-all. Tests already exist that catch this by adding a public folder to the existing `basepath` test suite
Fixes: https://github.com/vercel/next.js/issues/16332
Closes: https://github.com/vercel/next.js/pull/16350
Don't use this yet as it's still being developed. This is a first iteration that enables the webpack cache. There's still more to do here, for example if css modules are used there's currently a bug where webpack does not save the cache for browser compilation (impacting build performance). @sokra is going to look into that issue.
This pull request adds a test case for the reproduction provided in #12445. This bug is specifically caused when loading the next page before navigation has actually occurred.
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Fixes#12445
This fixes the incorrect `/_next/data` URL being generated on client transition due to the `as` value passed to `getRouteInfo` having the `basePath` which is used while interpolating the values for dynamic routes, specifically root catch-all routes. A regression test has also been added to ensure this is working
Closes: https://github.com/vercel/next.js/issues/15747
This updates to not automatically append params to the query for rewrites if one or more of the params are already used in the destination's path. No other behavior is being changed and if the user still wants the params in the query after using them in the destination's path they can manually add them like with redirects.
Closes: https://github.com/vercel/next.js/issues/15626
This pull request edits the `BuildManifest` that is sent to `/_document` instead of modifying a single input array to decouple its implementation details.
Optimally, we'd eliminate the `files` key all together.
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Related to #16182
This PR removes a legacy router method that was used for old-style HMR, now replaced by Fast Refresh.
This method was not public:
```tsx
export type NextRouter = BaseRouter &
Pick<
Router,
| 'push'
| 'replace'
| 'reload'
| 'back'
| 'prefetch'
| 'beforePopState'
| 'events'
| 'isFallback'
>
```
Even if someone found this method, it's highly unlikely they could use it successfully—it required the full module object.
This PR adds a second experimental post-processing step for the framework introduced by @prateekbh in #14746. The image post-processing step scans the rendered document for the first few images and uses a simple heuristic to determine if the images should be automatically preloaded.
Analysis of quite a few production Next apps has shown that a lot of sites are taking a substantial hit to their [LCP](https://web.dev/lcp/) score because an image that's part of the "hero" element on the page is not preloaded and is getting downloaded with lower priority than the JavaScript bundles. This post-processor should automatically fix that for a lot of sites, without causing any real performance effects in cases where it fails to identify the hero image.
This feature is behind an experimental flag, and will be subject to quite a bit of experimentation and tweaking before it's ready to be made a default setting.
By popular request, this pull request adds support for returning `fallback: 'blocking'` from `getStaticPaths`.
This new mode will cause unknown paths to be rendered on-demand ("SSR") without the static (placeholder) fallback.
This feature is **currently experimental and should not be used in production yet**. It's currently flagged behind `unstable_`:
```
fallback: 'unstable_blocking'
```
TODO:
- [x] Next.js tests
- [ ] Add Vercel support
- [ ] Vercel tests
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Fixes#15637
In terms of url rewriting, `trailingSlash` supports everything `exportTrailingSlash` does. We can just share all other code paths and deprecate `exportTrailingSlash`.
This PR shows a deprecation warning when `exportTrailingSlash` is used.
Also fixes https://github.com/vercel/next.js/issues/15774
We can update the tests now or later. (I kept them the same to prove it's non-breaking)
To do:
- [x] Do we want to keep this? => nope 841d4efc51/packages/next/next-server/lib/router/router.ts (L329)
- [x] I kept `exportTrailingSlash` here. Do we want to rename that as well? => nope 2d9d649d49/packages/next/build/index.ts (L959)
This updates collecting dynamic route params on Vercel to make sure that missing optional dynamic routes are undefined. Additional tests for this mode have also been added to ensure the params are being collected properly
Closes: https://github.com/vercel/next.js/issues/15579