### What?
This PR adds a new flag called
`experimental.missingSuspenseWithCSRBailout`.
### Why?
Via this PR we can break a build when calling `useSearchParams` without
wrapping it in a suspense boundary.
If no suspense boundaries are present, Next.js must avoid doing SSR and
defer the entire page's rendering to the client. This is not a great
default. Instead, we will now break the build so that you are forced to
add a boundary.
### How?
Add an experimental flag. If a `BailoutToCSRError` error is thrown and
this flag is enabled, the build should fail and log an error, instead of
showing a warning and bail the entire page to client-side rendering.
Closes NEXT-1770
---------
Co-authored-by: Balázs Orbán <info@balazsorban.com>
Co-authored-by: Wyatt Johnson <accounts+github@wyattjoh.ca>
### What?
In the previous PR (#60249), it was found that the case when the
response size is larger than 2MB is not sufficiently covered by tests
[[comment](https://github.com/vercel/next.js/pull/60249#pullrequestreview-1807140518)]
### How?
I added a few more checks.
Just checking the number of API calls is not enough - I believe it is
important to additionally verify what exactly the page received.
If I'm honest, I couldn't find the exact reason why data is loaded after
application start when using `customCacheHandler`, but without it -
during build. It seems like something in the butcher. Therefore, in this
part, I simply configured it for the current version.
---------
Co-authored-by: JJ Kasper <jj@jjsweb.site>
### What?
When accessing `params` on a `RootLayout`, while also using parallel
routes, two potential errors would occur:
- A `Warning: React.createElement: type is invalid` error when
attempting to render a `NotFound` component that doesn't exist
- A `TypeError: Cannot read properties of undefined` error when
attempting to access params in the root layout.
### Why?
`createComponentTree` will render a duplicate `RootLayout` (to ensure
the `notFound()` fallback in unmatched parallel slots have a
`NotFoundBoundary` to catch them) but it currently doesn't ensure a
`NotFound` component exists nor does it forward `params` to the layout.
### How?
This forwards the params to the `RootLayout` and doesn't render a
`NotFoundComponent` if one doesn't exist. This replaces a few `any`
types with more sound types that would have helped catch these mistakes.
There's still a lot more typing that needs to be done (left a comment
below with some additional details) but I opted to make the minimal
changes related to this issue.
Longer term we should remove this duplicate `RootLayout` (see #60220)
which will require special UI to show unmatched slots (similar to the
error overlay, but less harsh)
Closes NEXT-1909
Fixes#59711
### What
Fix bad detection of dynamic route of sitemap metadata route, the swc
AST check should process when the text are detected. But prevuious if
there's text with `generateSitemap` such as comment but not the actual
export it will fail.
### How
Add both checks on metadata loader side and detection helper side
* Only call `generateSitemaps` helper when the export existed
* Fix the helper detection logic (major part of this PR)
Fixes#59698Closes#60344
Closes NEXT-2007
### What?
Our
[docs](https://nextjs.org/docs/app/building-your-application/routing/parallel-routes#convention)
point out that `app/page.js` is equivalent to `app/@children/page.js`,
however in practice this is not the case, and causes type errors when
using `@children` slots as well as incorrect behavior when matching
catch-all routes.
### Why?
- When typechecking, `@children` slots would be added to the typeguard
file for the associated layout, resulting in duplicate identifiers for
the `children` prop
- When determining where to insert catchall slots, the `hasMatchedSlots`
check wasn't considering that the `@children` slot corresponds with the
page component, so matching another page would clobber the previous one.
### How?
- Filters out the `@children` slot when collecting slots for
typechecking
- Filters out the `@children` slot when running the `hasMatchedSlots`
function in the catch-all normalizer
Closes NEXT-1984
### What?
When relying on a `default` route as a fallback, greedier catch-all
segments in the application hierarchy would take precedence, causing
unexpected errors/matching behavior.
### Why?
When performing parallel route catch-all normalization, we push
potential catch-all matches to paths without considering that a path
might instead be matched by a `default` page. Because of this, the
catch-all take precedence and the app will not try and load the default.
For example, given this structure:
```
{
"/": ["/page"],
"/[[...catchAll]]": ["/[[...catchAll]]/page"],
"/nested/[foo]/[bar]": ["/nested/[foo]/[bar]/@slot/page"],
"/nested/[foo]/[bar]/[baz]": ["/nested/[foo]/[bar]/@slot/[baz]/page"],
}
```
(Where there's a `/nested/[foo]/[bar]/default.tsx`)
The route normalization logic would produce:
```
{
"/": ["/page"],
"/[[...catchAll]]": ["/[[...catchAll]]/page"],
"/nested/[foo]/[bar]": [
"/nested/[foo]/[bar]/@slot/page",
"/[[...catchAll]]/page",
],
"/nested/[foo]/[bar]/[baz]": [
"/nested/[foo]/[bar]/@slot/[baz]/page",
"/[[...catchAll]]/page",
],
}
```
This means that when building the `LoaderTree`, it won't ever try to
find the default for that segment. **This solution operates under the
assumption that if you defined a `default` at a particular layout
segment, you intend for that to render in place of a greedier
catch-all.** (Let me know if this is an incorrect assumption)
### How?
We can't safely normalize catch-all parallel routes without having
context about where the `default` segments are, so this updates
`appPaths` to be inclusive of default segments and then filters them
when doing anything relating to build/export to maintain existing
behavior. We use this information to check if an existing default exists
at the same segment level that we'd push the catch-all to. If one
exists, we don't push the catch-all. Otherwise we proceed as normal.
Closes NEXT-1987
This fixes a case in the PPR navigations implementation where page data
was not being applied.
During a navigation, we compare the route trees of the old and new pages
to determine which layouts are shared. If the segment keys of two
layouts are the same, they are reused.
However, the server doesn't bother to assign segment keys to the leaf
segments (which we refer to as "page" segments) because they are never
part of a shared layout. It assigns all of them a special constant
(`__PAGE__`).
In the PPR implementation, I overlooked this and compared the segment
keys of all segments, including pages, not just shared layouts. So if
the only thing that changed during a navigation was the page data, and
not any parent layout, the client would fail to apply the navigation.
The fix is to add a special case for page segments before comparing
nested layouts. I also moved an existing special case for default pages,
since those are also leaf segments and are conceptually similar.
### Fixing a bug
### What?
Disable 2MB limit for custom incrementalCacheHandler
### Why?
The limit is necessary because `FetchCache` has a 2MB limit, but it
seems there was a miscommunication regarding the key coincidence, where
`fetchCache` is a flag indicating that the method is called from fetch,
rather than indicating that the `FetchCache` Provider is currently being
used.
We do not use Vercel, and as I understand it, we do not have the
opportunity to use this functionality.
In any case, it is more important for us to increase the limits, and in
some cases, using a file storage is even preferable.
### How?
I have created a flag that determines whether the use of `FetchCache` is
possible at least in theory - if no custom provider is passed, and
additionally configured it so that it is not an implementation of
`FetchCache` as a protection against special individuals (*like me :)*).
If everything is fine, I will write proper tests.
Also, I would like to recommend making `FileSystemCache` public (_i.e.
support it as public functionality_) so that it can be imported and
extended or simply used to fix only it.
Fixes#48324 (partially)
---------
Co-authored-by: JJ Kasper <jj@jjsweb.site>
### What & Why?
When visiting a route that attempts to render a slot with no page & no default, the fallback behavior is to trigger a 404. However this can lead to a confusing development experience for complex parallel routing cases as you might not realize a default is missing, or which slot is causing the error.
Previous issues where this caused confusion:
- https://github.com/vercel/next.js/issues/51805
- https://github.com/vercel/next.js/issues/49569
### How?
This is a dev-only modification to track parallel slots that are using the default fallback (aka missing). When the `NotFoundBoundary` is triggered in development mode, this will log a warning about why it 404ed, along with a list of slot(s) that were determined to be missing.
### Future
We should eventually lift this into some sort of dev-only UI to help catch it when not monitoring the browser console (similar to the error overlay). However, this will require some design thought and isn't necessary for the first iteration.
Closes NEXT-1798
## What?
Currently there is a bug in Server Actions when you `fetch` as it uses
the same defaults (caching when not specified) as rendering, this causes
some issues as you want to read your writes in Server Actions.
This change adds the `no-store` default for Server Actions, you can
still override it by specifying `cache: 'force-cache'` for example, but
it defaults to `cache: 'no-store'`.
Fixes NEXT-1926
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---------
Co-authored-by: Zack Tanner <zacktanner@gmail.com>
Previously in #58967 we set all the module type as `'es6'` to let swc
parse app router code as ESM and output as ESM due to the incorrect
detection of CJS module by auto-cjs plugin, but this is not accurate
when the external library bundle is CJS. The problem is when swc
compiling modern syntax for example private properties in CJS bundle but
emitted the swc helpers with ESM imports.
We had a auto-cjs swc plugin to determine if the file is using CJS or
not, @kdy1 fixed the bug of it so now we can use the default module
type, and let the plugin to determine its module type, to make sure
we're emitting the right helpers.
Closes NEXT-1942
Based on #60118
Use dynamic import instead of require to load the incremental cache
handled, so when using ESM it will still work.
Updated the tests and merged them into new test suite, include 3 cases
of custom cache definition:
- CJS with `module.exports`
- CJS with `exports.default` with ESM mark
- ESM with `export default`
Closes NEXT-1924
Fixes#58509
This adds a test that verifies that the search parameters sent to the
server while Partial Prerendering is enabled is actually sent and can be
used by the page.
Closes NEXT-1890
## What
When users specify `"type": "module"` in Next.js app, especially with
`create-next-app`, `Image` component is not working. An error
`Unsupported Server Component type: {...}` is thrown.
## Why
`next/image` API is mixing with a client component as default export and
a named export as server component. But the entry file of the API is
still CJS file, which will import the module as the object. So you'll
get `{ default, unstable_getImageProps }` when you do `import Image from
'next/image'` instead of `Image` component itself, where the CJS module
load all the exports as an object. This is expected behavior for ESM but
breaks the usage.
It only errors when you're using js extensions, if you're using
typescript, it still works. If you're using turbopack, it works in dev
mode.
This is also because webpack can't analyze the exports from CJS module
of that `next/image` entry file. Usually we can assign the default
export to the module itself, then attach other named exports onto it, so
the default export equals the `module.exports` itself. But for
`next/image` since the default export is an client component, doing that
will error with React as you cannot modify the react client reference.
Turbopack doesn't use the same way to analyze the default export, so it
doesn't have this problem.
## How
We create few ESM version of entry files of nextjs APIs, then pick up
them to let app router for bundling, instead of using the `next/<api
name>.js` CJS files. Those ESM entries still point to the `next/dist/..`
CJS files. In this way webpack and directly gets the exports from the
`next/dist/...` files and be aware of the module exports. No more CJS
module wrapping the ESM module, the default and named exports can
preserve correctly.
Fixes#54777
Closes NEXT-1774
Closes NEXT-1879
Closes NEXT-1923
### What?
When handling route interception in two different segments but handled
by the same interception route, the first interception will show the
correct component but attempting the same interception on another
segment will return elements from the first request, not the second.
### Why?
Prefetch cache entries are created from the browser URL. However, route
interception makes use of `nextUrl` to mask the underlying components
that are being fetched from the server to handle the request
Consider the following scenario:
```
app
foo
@modal
(...)post
[id]
bar
@modal
(...post)
[id]
post
[id]
```
If you trigger an interception on `/foo`, your URL is going to be masked
to `/post/1` and keyed as such in the prefetch cache. However, the cache
entry is actually associated with `app/foo/@modal/(...post)/[id]`. That
means when you trigger the same interception on `/bar`, it will return
the tree from `/foo`.
### How?
This PR will prefix the prefetch cache key with `state.nextUrl` when
necessary.
Fixes#49878Fixes#52748
Closes NEXT-1818
### What?
Catch-all routes are being matched to parallel routes which causes
issues like an interception route being handled by the wrong page
component, or a page component being associated with multiple pages
resulting in a "You cannot have two parallel pages that resolve to the
same path" build error.
### Why?
#58215 fixed a bug that caused catchall paths to not properly match when
used with parallel routes. In other words, a catchall slot wouldn't
render on a page that could match that catch all. Or a catchall page
wouldn't match a slot. At build time, a normalization step was
introduced to take application paths and attempt to perform this
matching behavior.
However in it's current form, this causes the errors mentioned above to
manifest. To better illustrate the problem, here are a few examples:
Given:
```
{
'/': [ '/page' ],
'/[...slug]': [ '/[...slug]/page' ],
'/items/[...ids]': [ '/items/[...ids]/page' ],
'/(.)items/[...ids]': [ '/@modal/(.)items/[...ids]/page' ]
}
```
The normalization logic would produce:
```
{
'/': [ '/page' ],
'/[...slug]': [ '/[...slug]/page' ],
'/items/[...ids]': [ '/items/[...ids]/page' ],
'/(.)items/[...ids]': [ '/@modal/(.)items/[...ids]/page', '/[...slug]/page' ]
}
```
The interception route will now be improperly handled by
`[...slug]/page` rather than the interception handler.
Another example, which rather than incorrectly handling a match, will
produce a build error:
Given:
```
{
'/': [ '/(group-b)/page' ],
'/[...catcher]': [ '/(group-a)/@parallel/[...catcher]/page' ]
}
```
The normalization logic would produce:
```
{
'/': [ '/(group-b)/page', '/(group-a)/@parallel/[...catcher]/page' ],
'/[...catcher]': [ '/(group-a)/@parallel/[...catcher]/page' ]
}
```
The parallel catch-all slot is now part of `/`. This means when building
the loader tree, two `children` parallel segments (aka page components)
will be found when hitting `/`, which is an error.
The error that was added here was originally intended to help catch
scenarios like:
`/app/(group-a)/page` and `/app/(group-b)/page`. However it also throws
for parallel slots, which isn't necessarily an error (especially since
the normalization logic will push potential matches).
### How?
There are two small fixes in this PR, the rest are an abundance of e2e
tests to help prevent regressions.
- When normalizing catch-all routes, we will not attempt to push any
page entrypoints for interception routes. These should already have all
the information they need in `appPaths`.
- Before throwing the error about duplicate page segments in
`next-app-loader`, we check to see if it's because we already matched a
page component but we also detected a parallel slot that would have
matched the page slot. In this case, we don't error, since the app can
recover from this.
- Loading a client reference manifest shouldn't throw a cryptic require
error. `loadClientReferenceManifest` is already potentially returning
undefined, so this case should already be handled gracefully
Separately, we'll need to follow-up on the Turbopack side to:
- Make sure the duplicate matching matches the Webpack implementation (I
believe Webpack is sorting, but Turbopack isn't)
- Implement #58215 in Turbopack. Once this is done, we should expect the
tests added in this PR to start failing.
Fixes#58272Fixes#58660Fixes#58312Fixes#59782Fixes#59784
Closes NEXT-1809
Adds a regression test and a fix for a bug that sometimes happens when a
prefetched route on the client becomes stale — the app would get stuck
in a loading state.
The problem was the condition I used to fallback to the non-PPR
implementation, inside navigateReducer. It was too narrow, causing
prefetched segments that contained dynamic holes to sometimes be treated
as if they were complete. The net effect was that the dynamic data would
never stream in, and the page would get stuck in a fallback state until
the stale prefetch was eventually purged from the cache, or the user
refreshed the page.
The reason the mistake happened was, as an incremental step, I decided
to fallback to the non-PPR implementation for any case where I hadn't
yet implemented the equivalent functionality. I think still think this
is a good strategy, despite the mistake, but I'm eager to get everything
migrated to the new model as soon as possible.
Closes NEXT-1920
If a user accidentally configures a non-valid `revalidate` value this
ensures we show a proper error message instead of silently tolerating
it.
Closes: NEXT-1896
Closes NEXT-1915
In #59725 I skipped this test in PPR prod mode, but not dev because CI
wasn't failing for dev. The idea was to investigate the failure
post-merge because it wasn't block-worthy.
But the test did fail in dev mode when CI ran on canary. So this updates
the guard to skip in dev, too.
Will follow up with a PR to fix the test itself.
Closes NEXT-1913
For a more detailed explanation of the algorithm, refer to the comments
in ppr-navigations.ts. Below is a high-level overview.
### Step 1: Render the prefetched data immediately
Immediately upon navigation, we construct a new Cache Node tree (i.e.
copy-on-write) that represents the optimistic result of a navigation,
using both the current Cache Node tree and data that was prefetched
prior to navigation.
At this point, we haven't yet received the navigation response from the
server. It could send back something completely different from the tree
that was prefetched — due to rewrites, default routes, parallel routes,
etc.
But in most cases, it will return the same tree that we prefetched, just
with the dynamic holes filled in. So we optimistically assume this will
happen, and accept that the real result could be arbitrarily different.
We'll reuse anything that was already in the previous tree, since that's
what the server does.
New segments (ones that don't appear in the old tree) are assigned an
unresolved promise. The data for these promises will be fulfilled later,
when the navigation response is received.
The tree can be rendered immediately after it is created. Any new trees
that do not have prefetch data will suspend during rendering, until the
dynamic data streams in.
### Step 2: Fill in the dynamic data as it streams in
When the dynamic data is received from the server, we can start filling
in the unresolved promises in the tree. All the pending promises that
were spawned by the navigation will be resolved, either with dynamic
data from the server, or `null` to indicate that the data is missing.
A `null` value will trigger a lazy fetch during render, which will then
patch up the tree using the same mechanism as the non-PPR implementation
(serverPatchReducer).
Usually, the server will respond with exactly the subset of data that
we're waiting for — everything below the nearest shared layout. But
technically, the server can return anything it wants.
This does _not_ create a new tree; it modifies the existing one in
place. Which means it must follow the Suspense rules of cache safety.
## To Do
Not all necessarily PR-blocking, since the status quo is that
navigations don't work at all when PPR is enabled
- [x] Figure out how to handle dynamic metadata. Need to switch from
prefetched metadata to final.
- [x] Some mistake related to parallel routes, need to look into failing
tests
Closes NEXT-1894
### What?
Navigating to a layout that is part of a route group that uses route
interception currently will trigger a 404 error if the route group
doesn't define a `default` segment.
### Why?
When `next-app-loader` injects fallback defaults into the loader tree,
it does so by first seeing if a default already exists. However it does
this without ignoring route groups, meaning if you have a
`/app/default.tsx` and your interception route is at
`/app/(level1)/(level2)`, it will look for the default at
`/app/(level1)/(level2)/default.tsx`.
When a `default` isn't found, the fallback behavior is to trigger a
`notFound()` error. This means navigating to the intercepting route that
has no `default` for the `children` segment will 404.
### How?
This adjusts the fallback behavior by attempting to find the `default`
by normalizing the segment path, which will ignore route groups. That
way `/app/(level1)/(level2)/default` will first check `/app/default.tsx`
before falling back to `notFound` behavior.
Fixes#59279
Closes NEXT-1813
### What?
There are a bunch of different bugs caused by the same underlying issue,
but the common thread is that performing any sort of router cache update
(either through `router.refresh()`, `revalidatePath()`, or `redirect()`)
inside of a parallel route would break the router preventing subsequent
actions, and not resolve any pending state such as from `useFormState`.
### Why?
`applyPatch` is responsible for taking an update response from the
server and merging it into the client router cache. However, there's
specific bailout logic to skip over applying the patch to a
`__DEFAULT__` segment (which corresponds with a `default.tsx` page).
When the router detects a cache node that is expected to be rendered on
the page but contains no data, the router will trigger a lazy fetch to
retrieve the data that's expected to be there
([ref](5adacb6912/packages/next/src/client/components/layout-router.tsx (L359-L370)))
and then update the router cache once the data resolves
([ref](5adacb6912/packages/next/src/client/components/layout-router.tsx (L399-L404))).
This is causing the router to get stuck in a loop: it'll fetch the data
for the cache node, send the data to the router reducer to merge it into
the existing cache nodes, skip merging that data in for `__DEFAULT__`
segments, and repeat.
### How?
We currently assign `__DEFAULT__` to have `notFound()` behavior when
there isn't a `default.tsx` component for a particular segment. This
makes it so that when loading a page that renders a slot without slot
content / a `default`, it 404s. But when performing a client-side
navigation, the intended behavior is different: we keep whatever was in
the `default` slots place, until the user refreshes the page, which
would then 404.
However, this logic is incorrect when triggering any of the above
mentioned cache node revalidation strategies: if we always skip applying
to the `__DEFAULT__` segment, slots will never properly handle reducer
actions that rely on making changes to their cache nodes.
This splits these different `applyPatch` functions: one that will apply
to the full tree, and another that'll apply to everything except the
default segments with the existing bailout condition.
Fixes#54173Fixes#58772Fixes#54723Fixes#57665
Closes NEXT-1706
Closes NEXT-1815
Closes NEXT-1812
This fixes some of headers (and adds associated tests) for pages when
PPR is enabled. Namely, the `Cache-Control` headers are now returning
correctly, reflecting the non-cachability of some requests:
- Requests that postpone (dynamic data is streamed after the initial
static shell is streamed)
- Requests for the Dynamic RSC payload
Additionally, the `X-NextJS-Cache` header has been updated for better
support for PPR:
- Requests that postpone no longer return this header as it doesn't
reflect the cache state of the request (because it streams)
- Requests for the Prefetch RSC now returns the correct cache headers
depending on the segment and pre-postpone state
This also enables the other pathnames in the test suites 🙌🏻
Closes NEXT-1840
## What?
Adds two tests for server actions returning client components:
- (supported) Importing a server action from a server component. That
server action imports a client component and returns it.
- (not supported yet) Importing a server action from a client component.
The server action imports a client component and returns it.
The second case is not supported yet as it would effectively mean a
compilation loop:
`server` -> `client` -> `server` -> `client`
and if that last client component includes another server action it goes
even further:
`server` -> `client` -> `server` -> `client` -> `server` (and if that
server action includes anothe client component it goes further and
further)
Whereas currently it's only `server` -> `client` -> `server`, so it's
limited to that.
In the future we should be able to support this
server->client->server->client loop in Turbopack specifically because
Turbopack has a single module graph.
Importing the client component in a server action that is defined in the
server compiler (i.e. when created inline or when imported from a server
component) it does work correctly already.
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Closes NEXT-1873
This ensures that `export const dynamic = 'force-static'` is properly
honored when a page contains fetches with `cache: 'no-store'`, `cache:
'no-cache'` or `next: { revalidate: 0 }`.
Closes NEXT-1858
Before PPR, the way instant navigations work in Next.js is we prefetch
everything up to the first route segment that defines a loading.js
boundary. The rest of the tree is defered until the actual navigation.
It does not take into account whether the data is dynamic — even if the
tree is completely static, it will still defer everything inside the
loading boundary.
The approach with PPR is different — we prefetch as deeply as possible,
and only defer when dynamic data is accessed. If so, we only defer the
nearest parent Suspense boundary of the dynamic data access, regardless
of whether the boundary is defined by loading.js or a normal <Suspense>
component in userspace.
This PR removes the partial behavior of loading.js when the PPR flag is
enabled. In effect, loading.js now acts like a regular Suspense boundary
with no additional special behavior.
Note that in practice this usually means we'll end up prefetching more
than we were before PPR, which may or may not be considered a
performance regression by some apps. The plan is to address this before
General Availability of PPR by introducing granular per-segment
fetching, so we can reuse as much of the tree as possible during both
prefetches and dynamic navigations. But during the beta period, we
should be clear about this trade off in our communications.
## Testing strategy
While I was writing a test, I noticed that it's currently pretty
difficult to test all the scenarios that PPR is designed to handle, so I
gave special attention to setting up a testing strategy that I hope will
make this easier going forward. The overall pattern is based on how
we've been testing concurrent rendering features in the React repo for
many years:
- In the e2e test, spin up an HTTP server for responding to requests
sent by the test app. This simulates the data service that would be used
in a real Next.js application, whether it's direct db access, an ORM, or
a higher-level data access layer. The e2e test can observe when
individual requests are received, and control the timing of when the
data is fulfilled, without needing to mock any lower level I/O. (We're
already using a similar pattern to [test fetch
deduping](a3616d33ed/test/e2e/app-dir/app-fetch-deduping/app-fetch-deduping.test.ts (L8-L29)).)
- Each time a request is received, write to an event log. Then assert on
the result of the log at different points throughout the test. This
helps catch subtle mistakes where the order of events is not expected,
or the same event happens more than it should.
(I wrote some test helpers, but to avoid early abstraction, I've
intentionally not moved them into a separate module.)
Closes NEXT-1779
### What?
switch turbopack to use a single client components entrypoint for all
client components on a page for development. This aligns it with the
webpack behavior.
### Why?
compiling a separate entrypoint for every client component is pretty
expensive in regards of compilation, chunking, code generation, file
writing and number of requests.
### Turbopack Changes
* https://github.com/vercel/turbo/pull/6713 <!-- Tobias Koppers - use
real emojis -->
* https://github.com/vercel/turbo/pull/6728 <!-- Tobias Koppers - fix
order of reverse topologic iteration -->
Closes PACK-2115
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Fixes#58087
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fixes#58087
Currently in Next 14, everyone has fullURL flag turned to true, this PR
reverts the condition.
---------
Co-authored-by: Jiachi Liu <inbox@huozhi.im>
### What?
While scrolled on a page, and when following a link to a new page and
clicking the browser back button or using `router.back()`, the scroll
position would sometimes restore scroll to the incorrect spot (in the
case of the test added in this PR, it'd scroll you back to the top of
the list)
### Why?
The refactor in #56497 changed the way router actions are processed:
specifically, all actions were assumed to be async, even if they could
be handled synchronously. For most actions this is fine, as most are
currently async. However, `ACTION_RESTORE` (triggered when the
`popstate` event occurs) isn't async, and introducing a small amount of
delay in the handling of this action can cause the browser to not
properly restore the scroll position
### How?
This special-cases `ACTION_RESTORE` to synchronously process the action
and call `setState` when it's received, rather than creating a promise.
To consistently reproduce this behavior, I added an option to our
browser interface that'll allow us to programmatically trigger a CPU
slowdown.
h/t to @alvarlagerlof for isolating the offending commit and sharing a
minimal reproduction.
Closes NEXT-1819
Likely addresses #58899 but the reproduction was too complex to verify.
## What?
- Add support for `experimental.externalDir` -- Was already supported,
just makes Turbopack not fail on that config option
- Skipped `with-babel` test because it tests Babel
- Skipped `swc-warnings` test because it tests Babel
- Skipped `config-resolve-alias` as it tests webpack config
- Skipped `undefined-webpack-config` as it tests webpack config
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Closes NEXT-1817
### What?
Visiting an edge catch-all route incorrectly truncates multiple
parameters
### Why?
The params are currently coerced into a `ParsedURLQuery`-like format by
calling `Object.fromEntries` on `searchParams`, but this doesn't
consider multiple param values assigned to the same key
### How?
Rather than use `fromEntries`, this uses an existing util to get the
path into `ParsedURLQuery` format.
Closes NEXT-1814
Fixes#59333
This makes some critical modifications to the app render pipeline when
PPR has been enabled for pages with segments defining:
```js
export const dynamic = "force-dynamic"
```
Importantly, it no longer modifies the revalidation time to zero for
those pages, and now falls back to the provided default revalidation
time. When static render occurs, if the page being rendered has a
segment config defining `dynamic === "force-dynamic"`, then it will
postpone at the root of the component tree. This ensures that no render
code is executed for the page, as the entirety of the tree will have
postponed. This fixes the bug where the flight prefetch wasn't generated
correctly as well.
### What?
Using an interception marker next to a dynamic segment does not behave
properly when deployed to Vercel
### Why?
The named route regex that gets created is not accounting for the
interception marker, which is causing the non-intercepted route to match
the intercepted serverless function.
### How?
This factors in the interception marker when building the named route
regex so that the non-intercepted route regex properly matches when
loading the non-intercepted page.
Deployment verified here: https://test-intercept-mu.vercel.app/
Closes NEXT-1786
Fixes#54650
## What?
Skips more tests that are running `next build` which is not supported by
Turbopack yet.
## How?
Used an approach where all `next build` tests would fail if
`TURBOPACK=1` is set, which is how the tests run. This highlighted the
cases `next build` was still running.
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Closes NEXT-1791
### What?
When using a server action on an intercepted route, when submitting that
action, you'd expect it to correspond with the page you're currently on.
However if you have route interception set up, and you load the page
rather than the intercepted page, submitting the action would `POST` to
the intercepted page. This would result in a 404 error because the
action ID you're attempting to submit wouldn't be found on the requested
page.
### Why?
Interception routes rely on the `Next-Url` request header to determine
if an interception should occur via a rewrite. However, server actions
are submitted with this header as well, so the rewrite will be applied
to the `POST` request corresponding with a non-existent action, or an
action on the intercepted page.
### How?
When loading a page that has an intercepted route, `nextUrl` should be
consistent with URL derived from the flight router state tree. But when
an interception occurs via navigation, `nextUrl` will now deviate. I'm
using this to determine whether or not `Next-Url` should be forwarded
along in the `POST` request.
Closes NEXT-1436
Fixes#52591Fixes#49934
### What?
When using rewrites, in the scenario where a user visits an intercepted
route, reloads the page, goes back, and then revisits the same route, we
serve the page rather than the intercepted route.
### Why?
#59094 fixed the case where `ACTION_RESTORE` was not restoring `nextUrl`
properly. However there's a separate issue where when the `SERVER_PATCH`
action comes in, `handleMutable` attempts to compute `nextUrl` by
comparing the patched tree with the current tree. In the case of the
popstate event, both trees are the same, so the logic is currently
configured to fallback to `canonicalUrl`, which is not the correct URL
to use in the case of rewrites.
### How?
If the computed changed path is null, we should only fallback to using
`canonicalUrl` if we don't have a valid `nextUrl` that we can use.
Closes NEXT-1747
Fixes#56072
