- Implements failing test
- Implemented handling for the case where the router tree does not match up with the segment path being navigated to. This is what caused the underlying error.
## Bug
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## Feature
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## Documentation / Examples
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Move react-dev-overlay into hot reloader client components, and let it imported by app router. So then we don't need to have hot reloader and react tree as adjacent sibilings but the overlay with error boundary is wrapping the react tree
Co-authored-by: Tim Neutkens <6324199+timneutkens@users.noreply.github.com>
Since `next/dynamic` has client hooks that not compatible with server
components, and app renderer doesn't provide context (such as
`LoadableContext`) for it to use. Previously we provided a simple
replacement using `React.lazy` for `next/dynamic` if you want to use it
in appDir.
This PR always alias it to the `React.lazy ` implementation for appDir
so that user won't need to worry about the dynamic options. They can
only use `dynamic()` without 2nd options arg
```js
import dynamic from 'next/dynamic'
const Dynamic = dynamic(() => import('./dynamic-component'))
```
- Add a failing test for navigating between many levels of dynamic routes
- Create router tree during prefetch action so that it can be reused across multiple urls
- Ensure segmentPath is correct when rendering a subtree. Previously it would generate a segmentPath that starts at the level it renders at which causes the layout-router fetchServerResponse to inject `refetch` at the wrong level.
- Fixed a case where Segment was compared using `===` which is no longer valid as dynamic parameters are expressed as arrays. Used `matchSegment` helper instead.
## Bug
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
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## Feature
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Ensures the static generation case is covered. Checks
application/octet-stream client-side, if it's not does a full page
navigation.
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## Bug
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Making this function a noop on server for bundle size gains with DCE since most of the code is in an useEffect and is not gonna run
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This is a temporarily fix as discussed with @sebmarkbage. It will be superseded by async reducer functions once that's added.
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This reducer takes a good chunk of the bundle but is never run on the server so we can eliminate it. 5-10ms wins from my manual benchmark runs.
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Since React 18 returning `undefined` from components is allowed which renders to `undefined` in the RSC response so we need a separate prop to know if the loading boundary was provided.
Thanks to @finn-orsini who reported this problem.
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This updates to ensure we properly error during static generation when a
non-dynamic SSR error is thrown so that unexpected errors are not
tolerated. This also fixes the static generation async storage not being
shared correctly due to different instances being created during
bundling.
This PR changes the external module resolution to eagerly bundle
node_modules, and some specific Next.js internal modules, if on the
`WEBPACK_LAYERS.server` layer. While resolving corresponding packages,
we use the `react-server` export condition (fallbacks to default).
A follow-up PR will be adding a Next.js option to opt-out specific
packages from being bundled on the server layer.
## Bug
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feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
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## Documentation / Examples
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Leverages `AsyncLocalStorage` when available for handling static generation context and falls back to requiring render to be isolated when `AsyncLocalStorage` is not available.
Note: most changes are spacing so toggling to ignore spacing may make reviewing easier
Small change leveraging the `createFromFetch` method instead.
## Bug
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This is an initial implementation of the Server Components SWC
transformer. For the server graph, it detects client entries via the
`"client"` directive and transpile them into module reference code; for
the client graph, it removes the directives. And for both graphs, it
checks if there is any invalid imports for the given environment and
shows proper errors.
With that added, we can switch from `next-flight-client-loader` to
directly use the SWC loader in one pass. Next step is to get rid of the
`.client.` extension in other plugins.
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PR.
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x-ref: https://github.com/facebook/react/pull/25267
Bump the version of `react-server-dom-webpack` and use `experimental_use` to unwrap the promise to access RSC payload instead of using `readRoot`. `readRoot` is removed from the response type.
This masks flight parameters from middleware so it doesn't interfere with RSC or routing.
## Bug
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## Documentation / Examples
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Co-authored-by: Tim Neutkens <6324199+timneutkens@users.noreply.github.com>
- Use React.startTransition instead of useTransition
- Upgrade to latest React experimental
- Split router cache invalidate into separate function
Some minor cleanup while verifying behaviors.
Follow-up to #37551
Implements prefetching for the new router.
There are multiple behaviors related to prefetching so I've split them out for each case. The list below each case is what's prefetched:
Reference:
- Checkmark checked → it's implemented.
- RSC Payload → Rendered server components.
- Router state → Patch for the router history state.
- Preloads for client component entry → This will be handled in a follow-up PR.
- No `loading.js` static case → Will be handled in a follow-up PR.
---
- `prefetch={true}` (default, same as current router, links in viewport are prefetched)
- [x] Static all the way down the component tree
- [x] RSC payload
- [x] Router state
- [ ] preloads for the client component entry
- [x] Not static all the way down the component tree
- [x] With `loading.js`
- [x] RSC payload up until the loading below the common layout
- [x] router state
- [ ] preloads for the client component entry
- [x] No `loading.js` (This case can be static files to make sure it’s fast)
- [x] router state
- [ ] preloads for the client component entry
- `prefetch={false}`
- [x] always do an optimistic navigation. We already have this implemented where it tries to figure out the router state based on the provided url. That result might be wrong but the router will automatically figure out that
---
In the first implementation there is a distinction between `hard` and `soft` navigation. With the addition of prefetching you no longer have to add a `soft` prop to `next/link` in order to leverage the `soft` case.
A heuristic has been added that automatically prefers `soft` navigation except when navigating between mismatching dynamic parameters.
An example:
- `app/[userOrTeam]/dashboard/page.js` and `app/[userOrTeam]/dashboard/settings/page.js`
- `/tim/dashboard` → `/tim/dashboard/settings` = Soft navigation
- `/tim/dashboard` → `/vercel/dashboard` = Hard navigation
- `/vercel/dashboard` → `/vercel/dashboard/settings` = Soft navigation
- `/vercel/dashboard/settings` -> `/tim/dashboard` = Hard navigation
---
While adding these new heuristics some of the tests started failing and I found some state bugs in `router.reload()` which have been fixed. An example being when you push to `/dashboard` while on `/` in the same transition it would navigate to `/`, it also wouldn't push a new history entry. Both of these cases are now fixed:
```
React.startTransition(() => {
router.push('/dashboard')
router.reload()
})
```
---
While debugging the various changes I ended up debugging and manually diffing the cache and router state quite often and was looking at a way to automate this. `useReducer` is quite similar to Redux so I was wondering if Redux Devtools could be used in order to debug the various actions as it has diffing built-in. It took a bit of time to figure out the connection mechanism but in the end I figured out how to connect `useReducer`, a new hook `useReducerWithReduxDevtools` has been added, we'll probably want to put this behind a compile-time flag when the new router is marked stable but until then it's useful to have it enabled by default (only when you have Redux Devtools installed ofcourse).
> ⚠️ Redux Devtools is only connected to take incoming actions / state. Time travel and other features are not supported because the state sent to the devtools is normalized to allow diffing the maps, you can't move backward based on that state so applying the state is not connected.
Example of the integration:
<img width="1912" alt="Screen Shot 2022-09-02 at 10 00 40" src="https://user-images.githubusercontent.com/6324199/188637303-ad8d6a81-15e5-4b65-875b-1c4f93df4e44.png">
Follow-up to the earlier enabling of classes/variables etc.
Bug
Related issues linked using fixes #number
Integration tests added
Errors have helpful link attached, see contributing.md
Feature
Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
Related issues linked using fixes #number
Integration tests added
Documentation added
Telemetry added. In case of a feature if it's used or not.
Errors have helpful link attached, see contributing.md
Documentation / Examples
Make sure the linting passes by running pnpm lint
The examples guidelines are followed from our contributing doc
Co-authored-by: Steven <steven@ceriously.com>
WIP.
## Bug
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Co-authored-by: Shu Ding <3676859+shuding@users.noreply.github.com>
Use flush effects to custom apply css-in-js solution to app. Re-introduce flush effects to app-render, and remove default support of styled-jsx in `app/`. So that users will choose their own css-in-js solution if they need any customization. styled-jsx won't appear in client bundle if you didn't use it.
For now we have to inject the initial styles before `</head>` to avoid hydration errors. Later on we can remove this once react can handle it.
- [x] inject styles before end of head element
- [x] add tests
Add `next/dist/client/components/shared/dynamic` as shared api which server and client components can both support.
Dynamic imports will be part of flight on server side.
This pr doesn't contain preloading part for client components.
- Add additional comments for reducer functions.
- Add comments for CacheNode
## Bug
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Expand explanation of new router.
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Expanded app-render.
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Fixes the hash being overwritten when you open a page.
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Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
Ensures the `<html>` is not wrapped in an extra div when the root layout is nested in a route group.
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Follow-up to #38682. Instead of checking if the full element is in the viewport we only check if the top of the element is in the viewport. If it is not we have to scroll back up in cases of navigating between items in the same layout for example.
Temporarily we need to ensure that `<link>` tags are injected to `<head>` in the stream.
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Went through the todos I had added while implementing the new router and removes everything that is now covered.
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Temporary fix for refreshing of serverContext. We'll want to make a change for development with `createServerContext` to React itself in the future.
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* inject the link tags before page content in layout router
* fix flight handling during client navigation
* fix buffering
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
Renames todos to split them / make it easier to find what has to be done for the new router.
## Bug
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Handles the case where an error is introduced which causes a Fast Refresh and then it's fixed.
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Handles the case where you navigate between routes in `pages` and `app`.
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## Feature
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## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
- Remove cache value that was incorrectly nested deeper
- Remove extra useEffect (already applied during hydration based on the `useReducer` input)
- Add dynamic parameter name into the tree
Follow-up to #37551, cleans up some code and prepares for catch-all and optional catch-all routes.
## Client-side router for `app` directory
This PR implements the new router that leverages React 18 concurrent features like Suspense and startTransition.
It also integrates with React Server Components and builds on top of it to allow server-centric routing that only renders the part of the page that has to change.
It's one of the pieces of the implementation of https://nextjs.org/blog/layouts-rfc.
## Details
I'm going to document the differences with the current router here (will be reworked for the upgrade guide)
### Client-side cache
In the current router we have an in-memory cache for getStaticProps data so that if you prefetch and then navigate to a route that has been prefetched it'll be near-instant. For getServerSideProps the behavior is different, any navigation to a page with getServerSideProps fetches the data again.
In the new model the cache is a fundamental piece, it's more granular than at the page level and is set up to ensure consistency across concurrent renders. It can also be invalidated at any level.
#### Push/Replace (also applies to next/link)
The new router still has a `router.push` / `router.replace` method.
There are a few differences in how it works though:
- It only takes `href` as an argument, historically you had to provide `href` (the page path) and `as` (the actual url path) to do dynamic routing. In later versions of Next.js this is no longer required and in the majority of cases `as` was no longer needed. In the new router there's no way to reason about `href` vs `as` because there is no notion of "pages" in the browser.
- Both methods now use `startTransition`, you can wrap these in your own `startTransition` to get `isPending`
- The push/replace support concurrent rendering. When a render is bailed by clicking a different link to navigate to a completely different page that still works and doesn't cause race conditions.
- Support for optimistic loading states when navigating
##### Hard/Soft push/replace
Because of the client-side cache being reworked this now allows us to cover two cases: hard push and soft push.
The main difference between the two is if the cache is reused while navigating. The default for `next/link` is a `hard` push which means that the part of the cache affected by the navigation will be invalidated, e.g. if you already navigated to `/dashboard` and you `router.push('/dashboard')` again it'll get the latest version. This is similar to the existing `getServerSideProps` handling.
In case of a soft push (API to be defined but for testing added `router.softPush('/')`) it'll reuse the existing cache and not invalidate parts that are already filled in. In practice this means it's more like the `getStaticProps` client-side navigation because it does not fetch on navigation except if a part of the page is missing.
#### Back/Forward navigation
Back and Forward navigation ([popstate](https://developer.mozilla.org/en-US/docs/Web/API/Window/popstate_event)) are always handled as a soft navigation, meaning that the cache is reused, this ensures back/forward navigation is near-instant when it's in the client-side cache. This will also allow back/forward navigation to be a high priority update instead of a transition as it is based on user interaction. Note: in this PR it still uses `startTransition` as there's no way to handle the high priority update suspending which happens in case of missing data in the cache. We're working with the React team on a solution for this particular case.
### Layouts
Note: this section assumes you've read [The layouts RFC](https://nextjs.org/blog/layouts-rfc) and [React Server Components RFC](https://reactjs.org/blog/2020/12/21/data-fetching-with-react-server-components.html)
React Server Components rendering leverages the Flight streaming mechanism in React 18, this allows sending a serializable representation of the rendered React tree on the server to the browser, the client-side React can use this serialized representation to render components client-side without the JavaScript being sent to the browser. This is one of the building blocks of Server Components. This allows a bunch of interesting features but for now I'll keep it to how it affects layouts.
When you have a `app/dashboard/layout.js` and `app/dashboard/page.js` the page will render as children of the layout, when you add another page like `app/dashboard/integrations/page.js` that page falls under the dashboard layout as well. When client-side navigating the new router automatically figures out if the page you're navigating to can be a smaller render than the whole page, in this case `app/dashboard/page.js` and `app/dashboard/integrations/page.js` share the `app/dashboard/layout.js` so instead of rendering the whole page we render below the layout component, this means the layout itself does not get re-rendered, the layout's `getServerSideProps` would not be called, and the Flight response would only hold the result of `app/dashboard/integrations/page.js`, effectively giving you the smallest patch for the UI.
---
Note: the commits in this PR were mostly work in progress to ensure it wasn't lost along the way. The implementation was reworked a bunch of times to where it is now.
Co-authored-by: Jiachi Liu <4800338+huozhi@users.noreply.github.com>
Co-authored-by: JJ Kasper <22380829+ijjk@users.noreply.github.com>
## Bug
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
