### What?
Parallel routes build in a weird and render in a weird way.
To render next.js always uses the last parallel route (alphabetically I
think) as that's most likely to be the root.
Building works in the opposite order, it goes from the first to the
last.
This is fine for the first render, but after that the renderer will only
check if the file for the last parallel route has a bundle on disk and
never request it to be updated.
1. match on routes
2. build match
3. check if the last parallel route bundle exists on disk
- if it doesn't so go back to step 2 with the next match
- the actual match gets thrown away
4. render with the bundle for the last parallel route
The condition in step 3 will always be true after an update, because it
was built for a previous request
To fix this, turbopack will now emit all parallel routes that match a
path every time one of them gets requested.
Closes PACK-3078
Fixes#65836
### What
When PPR is off, app router prefetches will render the component tree up
until it encounters a `loading` segment, at which point it'll just
return some metadata about the segment and won't do any further
rendering. This is an optimization to ensure prefetches are lightweight
and don't potentially invoke expensive dynamic subtrees. However,
there's a bug in this logic that is causing it to bail unexpectedly if a
segment deeper in the tree contained a `loading.js` file.
This would mean the loading state wouldn't be triggered until the second
request for the full RSC data is initiated, resulting in an unintended
delta between when a link is clicked and the loading state is shown.
### Why
The `shouldSkipComponentTree` flag was incorrectly being set to `true`
even if the `loading.js` segment appeared deeper in the tree. Prefetch
requests from the client will always contain `FlightRouterState`, so the
logic to check for loading deeper in the tree will always be missed.
### How
This removes the `flightRouterState` check as it doesn't make sense:
prefetches will currently _always_ include the `flightRouterState`,
causing this to always short-circuit. I believe that this check is
vestigial from when we were generating static `prefetch.rsc` outputs
which is no longer the case.
This mirrors a [similar
check](b87d8fc499/packages/next/src/server/app-render/create-component-tree.tsx (L393))
when determining if parallel route(s) should be rendered.
When running `pnpm test-start
test/production/standalone-mode/required-server-files/required-server-files.test.ts`
locally, Jest hangs and prevents the process from exiting. In the CI,
the issue is masked because `run-tests.js` uses `--forceExit`.
The reason for the hanging process is that there are two server
instances started, and only the last one is killed. By starting and
killing the server for each test we can not only fix this, but also
prevent the `should run middleware correctly (without minimalMode, with
wasm)` test from affecting the other tests when flipping the
`minimalMode` flag in `server.js`.
I also reverted the darwin-specific overwrites of `appPort` that were
added in #65722 and #66724. I don't think those are needed because after
#65722 was created we did land #66285 which sets the hostname to be
compatible with ipv4 and ipv6. If there's still a need to keep this then
let me know, and I will restore it.
This leverages [fetch
priority](https://developer.mozilla.org/en-US/docs/Web/API/Request/Request#priority)
to ensure automatic prefetching as a result of visiting a page is sent
with "low" priority, to signal to the browser it can prioritize more
important work necessary for rendering the page.
A "temporary" prefetch (ie one that is created when there wasn't an
existing prefetch cache entry on navigation) will use a "high" priority
because it's critical to the navigation event.
All other cases will be "auto" which is the current default.
## History
When we added `priority` prop to `next/image`, there was no
`fetchPriority` so we instead used this to preload the image in the
head.
Then when browsers added support `fetchPriority`, we automatically added
`fetchPriority=high` when `priority={true}` to signal to the browser
that this was a high priority image. This priority is added to the img
and the preload.
However, we saw cases where images are blocking critical css. Per
@gnoff:
> React currently prioritizes font preloads then high priority images,
then css in the initial page load
Due to these changes in React (aka Float), we should no longer set
`fetchPriority=high`, although the user can still manually add that prop
if needed.
### Why?
Identified the bottleneck of Turbopack HMR, one of the reason is that we
run `execSync` to get user's package manager and fetch their registry to
get the latest & canary version of Next.js.
This process was located at the initial of HMR, which could have been
delayed to the initial of the error handling.
### How?
- Remove getting user's package manager and just fetch from NPM
regardless the user uses Yarn.
- Used an async IIFE to await the promise of `getVerionInfo` value
inside the synchronous `ws.handleUpgrade`.
### Benchmark
> Benchmarked with console inside try-finally
#### Webpack -- no cache
| Version | Ready |
|-------------------------------------|---------|
| Canary | 1185ms |
| Delta | 896ms |
| Delta Webpack vs Canary Webpack | -24.39% |
#### Turbopack
| Version | Ready |
|-------------------------------------|---------|
| Canary | 1002ms |
| Delta (Turbopack) | 509ms |
| Delta Turbopack vs Canary Turbopack | -49.20% |
---------
Co-authored-by: Jiachi Liu <inbox@huozhi.im>
Co-authored-by: Tobias Koppers <tobias.koppers@googlemail.com>
### What
* Warn with next.js when users customized `experimental.esmExternals`
value
* Add telemetry tracking on the customization usage for that flag. 0 for
no customization, 1 for used non-default customized value
### Why
`esmExternals` ideally can just remain as default value `true` which
Next.js can handle the customization properly. Since next.js app router
also supports it on canary now we're adding a warning to users that
don't modify `esmExternals` option as it could affect module resolution
on ESM packages.
### Why?
It could be confusing between `...` and `…`, which the later is actually
a single character.
### How?
We throw if we detect `…` instead of `...`.
The Image Optimization API currently uses `parseInt()` for `w` and `q`
query string parameters.
This doesn't handle floats as you might expect and instead coerces, for
example `parseInt('99.9') === 99`.
This PR changes the runtime to match the build time validation and only
accept integers for `w` and `q`.
When developing in Next.js repo, the maintainers / contributors
sometimes need to build swc native files.
Added a script `swc-build-native` to run the command `pnpm
--filter=@next/swc build-native` which was verbose to run.
Unstable Cache has always had a very lacking documentation page, even
though it adding its own new feature ``key parts`` . Its a normal
occurrence for us in the NextJS Discord to see new people and more
advanced users question what is the use of key parts, since the example
in the docs. was very lacking.
I have made a few changes, like adding a much more functional example
which showcases all the features of unstable cache, and also a small
difference section between tags and key parts.
---------
Co-authored-by: Sam Ko <sam@vercel.com>
## Why?
Add clarification that you need the experimental config:
```
module.exports = withMDX({
experimental: {
mdxRs: true,
},
})
```
when using [Turbopack](https://nextjs.org/docs/architecture/turbopack).
---------
Co-authored-by: Delba de Oliveira <32464864+delbaoliveira@users.noreply.github.com>
When a server action responds with something other than an RSC response,
we currently silently ignore the error and it doesn't get propagated to
any rejection handlers.
This adjusts the handling so that if the server action response is a
non-successful status code, we reject the server action promise. If the
error is `text/plain`, we'll automatically propagate the text content as
the error text. Otherwise, the promise is rejected with a fallback
message.
## Description
This Pull Request improves the visual appearance of the badges in the
README.md file by removing unnecessary line breaks between the badge
images, eliminating the unwanted blue link lines that previously
appeared and resulting in a cleaner and more cohesive look.
### What
Removed unnecessary line breaks between badge images in the README.md
file to eliminate the unwanted blue link lines and improve the overall
visual presentation.
### Why
Previously, the badges were displayed with line breaks between them,
causing blue link lines to appear, which disrupted the clean look of the
badges. By removing these line breaks, the badges now appear without the
blue link lines, providing a more cohesive and visually appealing
README.
### How
- Removed the line breaks between badge images in the README.md file.
Co-authored-by: Jiwon Choi <devjiwonchoi@gmail.com>
Fixes some possible race conditions by adding a few delays to the
navigation test to ensure that we wait for hydration to occur and
prefetches to finish.
### What?
Update the `with-mdx` example to MDX 3.
### Why?
The example was 2 major versions behind.
### How?
By updating the version in `package.json`. Also the `@mdx-js/react`
dependency was removed, as it doesn’t work with the app directory. Users
should use `mdx-components.tsx` instead.
Refs #59693
Co-authored-by: Sam Ko <sam@vercel.com>
Previously, when the provided postponed state was corrupted, the render
failed which resulted in a hydration error. Instead, when the postponed
state is corrupted, we send the resume stream just for the hydration
where it'll attempt to render client side with the data that's already
available.
…d not in another place.
"create-next-app" in apostrophe was mentioned twice but one with link
and second without link which didn't sync together for me. So, I added
the same link to the second one, maybe I am wrong.
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Co-authored-by: Jiwon Choi <devjiwonchoi@gmail.com>
### What?
This makes extracting next/dynamic cheaper when modules have been visited before
### Why?
improved HMR and page transitions
### How?
All steps for visiting a module are extracted into a single cached function. VIsiting already visited modules costs only a single cache lookup
