This pull request completely replaces our old page loader with a brand new route loader.
Our existing comprehensive test suite means I did not need to add a bunch of tests. I did add them where behavior was added or fixed.
Summary of the changes:
- Eagerly evaluates prefetched pages in browser idle time (speeds up transitions)
- Router is **no longer frozen** indefinitely if the Build Manifest never arrives
- Router is **no longer frozen** indefinitely if a page fails to bootstrap
- New `withFuture` utility instead of ad-hoc deduping per resource
- Prefetching is now delayed until browser idle time to not impact TTI
- Browsers without `prefetch` now fall back to eager evaluation instead of using `preload`
- We're now ready to serve non-static assets **with `no-store` without breaking prefetching**
- **Application can now hydrate without fetching CSS assets—this is a huge performance win that was previously blocking hydration**
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The minor size increase here is unfortunate, but we have to incur it for correctness.
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Fixes#18389Fixes#18642
This pull request speeds up Next.js' rendering pipeline by fetching data, parsing it, and loading it into memory instead of only doing the network request.
This will mainly result in improved Firefox/Safari performance since they handled prefetch incorrectly—only Chrome did it right. This also gets us closer to being able to use `no-store` in our caching headers!
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Fixes#18639
x-ref #18802
This makes sure we don't incorrectly strip locale characters from the path if it is not a locale prefix e.g. `/fr` should not be removed from `/frank`. Additional tests have been added to ensure this isn't stripped for this case.
Fixes: https://github.com/vercel/next.js/issues/18332
* Fix test without expect for redirects from getStaticProps/getServerSideProps
* Fix browser back issue of redirects from getServerSideProps / getStaticProps
This updates the fallback 404 handling to render the correct 404 page on the client when a 404 is returned from fetching the data route on a fallback page on the client. This prevents us from having to rely on a cache to be updated by the time we reload the page to prevent non-stop reloading.
This also adds handling in serverless mode to ensure the correct 404 page is rendered when leveraging fallback: 'blocking' mode.
Additional tests for the fallback: 'blocking' 404 handling will be added in a follow-up where returning notFound from `getServerSideProps` is also added.
This makes sure that we detect the correct default locale for domain specific locales since a domain can have a different default locale residing at the root and we need to check this on the client for prerendered/auto-static pages. This also makes sure we disable the built-in redirect handling when on Vercel since it's handled already.
Tests for this are tricky since we need to load the browser with a custom domain which requires editing the host file. Existing tests should ensure this doesn't break non-domain specific locale behavior though. This was also tested manually while testing https://github.com/vercel/vercel/pull/5298
x-ref: https://github.com/vercel/next.js/pull/17370
This adds the `locale` prop for `next/link` to allow transitioning between locales client-side and also allows passing the locale to `router.push/replace` via the transition options similar to `shallow` e.g. `router.push('/another', '/another, { locale: 'nl' })`
x-ref: https://github.com/vercel/next.js/pull/17370
Follow-up to https://github.com/vercel/next.js/pull/17370 this adds mapping of locales to domains and handles default locales for specific domains also allowing specifying which locales can be visited for each domain.
This PR also updates to output all statically generated pages under the locale prefix to make it easier to locate/lookup and to not redirect to the default locale prefixed path when no `accept-language` header is provided.
Follow-up PR to https://github.com/vercel/next.js/pull/17370 when the path is not prefixed with a locale and the default locale is the detected locale it doesn't redirect to locale prefixed variant. If the default locale path is visited and the default locale is visited this also redirects to the root removing the un-necessary locale in the URL.
This also exposes the `defaultLocale` on the router since the RFC mentions `Setting a defaultLocale is required in every i18n library so it'd be useful for Next.js to provide it to the application.` although doesn't explicitly spec where we want to expose it. If we want to expose it differently this can be updated.
This adds the initial changes outlined in the [i18n routing RFC](https://github.com/vercel/next.js/discussions/17078). This currently treats the locale prefix on routes similar to how the basePath is treated in that the config doesn't require any changes to your pages directory and is automatically stripped/added based on the detected locale that should be used.
Currently redirecting occurs on the `/` route if a locale is detected regardless of if an optional catch-all route would match the `/` route or not we may want to investigate whether we want to disable this redirection automatically if an `/index.js` file isn't present at root of the pages directory.
TODO:
- [x] ensure locale detection/populating works in serverless mode correctly
- [x] add tests for locale handling in different modes, fallback/getStaticProps/getServerSideProps
To be continued in fall-up PRs
- [ ] add tests for revalidate, auto-export, basePath + i18n
- [ ] add mapping of domains with locales
- [ ] investigate detecting locale against non-index routes and populating the locale in a cookie
x-ref: https://github.com/vercel/next.js/issues/17110
This makes sure we properly resolve a rewrite when only the `href` value is used. This was causing a full-reload and was missed in the existing test since we weren't making sure a full navigation didn't occur which has been added in this PR.
Fixes: https://github.com/vercel/next.js/issues/16974
This makes sure to strip the trailing slash before attempting to resolve the `href` against pages/dynamic routes and adds tests ensuring the correct pages are resolved with `trailingSlash: true` enabled.
Fixes: https://github.com/vercel/next.js/issues/16872
This makes sure we only pass the as value's `pathname` instead of the full value so that we don't accidentally include `query` values while resolving the rewrites. This also adds tests to ensure the rewrites are resolved with the correct query values when only providing `href` and when manually mapping them with `href` and `as`
Fixes: https://github.com/vercel/next.js/issues/16825
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
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 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 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.
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)
Fixes https://github.com/vercel/next.js/issues/15188
`parseRelativeUrl` was used on urls that weren't always relative. It was used to generate a cache key, but we actually don't need these cache keys to be relative if the urls aren't relative.
Also took a look at the overall static data fetching logic and found a few things:
- [x] cache key is unnecessarily transformed through `prepareRoute`, we can just cache by resolved `dataHref` and remove that function. Pretty sure that `prepareRoute` was also introducing edge cases with `assetPath` and `delBasePath`
- [x] there is [a bug in the caching logic](ebdfa2e7a3/packages/next/next-server/lib/router/router.ts (L898)) that made it fail on the second visit: it should be `Promise.resolve(this.sdc[pathname])` instead of `Promise.resolve(this.sdc[dataHref])`. Also added a test for this
- [x] ~converted to async await to improve stacktraces and readability.~ I assumed this was fine since I saw some async/awaits in that file already but it seems to just blow up the size of the non-modern bundle.
- [x] extracted nested `getResponse` function and define it top level. this should improve runtime performance
- [x] convert `_getStaticData` and `_getServerData` to class methods instead of properties. Not sure why they were defined as properties but I think they belong on the prototype instead.
- [x] remove `cb` property from `fetchNextData`, it's unnecessary and makes the async flow hard to understand. The exact same logic can go in the `.then` instead.
- [ ] data fetching logic [retries on 5xx errors](ebdfa2e7a3/packages/next/next-server/lib/router/router.ts (L157)), but not on network level errors. It should also retry on those. It should also not retry on every 5xx, probably only makes sense on 502, 503 and 504. (e.g. 500 is a server error that I wouldn't expect to succeed on a retry)
The overall result also is a few bytes smaller in size
