## Initial Pass
The initial pass applies to all user code. If an import (`foo`) matches one of the packages from our list, say:
```js
// user code
import { a } from 'foo'
import { otherThings } from './code'
```
The initial pass transforms it into:
```js
// user code
import { a } from '__barrel_optimize__?names=a!=!foo'
import { otherThings } from './code'
```
## Barrel Optimizations
This `__barrel_optimize__` loader is used to optimize the imports of "barrel" files that have many
re-exports. Currently, both Node.js and Webpack have to enter all of these
submodules even if we only need a few of them.
For example, say a file `foo.js` with the following contents:
```js
export { a } from './a'
export { b } from './b'
export { c } from './c'
...
```
If the user imports `a` only, this loader will accept the `names` option to
be `['a']`. Then, it request the `__barrel_transform__` SWC loader to load
`foo.js` (via `this.loadModule` Webpack API) and receive the following info:
```js
export const __next_private_export_map__ = '[["./a","a","a"],["./b","b","b"],["./c","c","c"],...]'
```
The export map, generated by SWC, is a JSON that represents the exports of
that module, their original file, and their original name (since you can do
`export { a as b }`).
Then, this loader can safely remove all the exports that are not needed and
re-export the ones from `names`:
```js
export { a } from './a'
```
That's the basic situation and also the happy path.
## Wildcard Exports
For wildcard exports (e.g. `export * from './a'`), it becomes a bit more complicated.
Say `foo.js` with the following contents:
```js
export * from './a'
export * from './b'
export * from './c'
...
```
If the user imports `bar` from it, SWC can never know which files are going to be
exporting `bar`. So, we have to keep all the wildcard exports and do the same
process recursively. This loader will return the following output:
```js
export * from '__barrel_optimize__?names=bar&wildcard!=!./a'
export * from '__barrel_optimize__?names=bar&wildcard!=!./b'
export * from '__barrel_optimize__?names=bar&wildcard!=!./c'
...
```
The "!=!" tells Webpack to use the same loader to process './a', './b', and './c'.
After the recursive process, the "inner loaders" will either return an empty string
or:
```js
export * from './target'
```
Where `target` is the file that exports `bar`.
## Non-Barrel Files
If the file is not a barrel, we can't apply any optimizations. That's because
we can't easily remove things from the file. For example, say `foo.js` with:
```js
const v = 1
export function b () {
return v
}
```
If the user imports `b` only, we can't remove the `const v = 1` even though
the file is side-effect free. In these caes, this loader will simply re-export
`foo.js`:
```js
export * from './foo'
```
Besides these cases, this loader also carefully handles the module cache so
SWC won't analyze the same file twice, and no instance of the same file will
be accidentally created as different instances.
---
- [x] Disable this loader for Jest
- [x] Add tests for SWC loader caching
- [x] Add tests for external modules
- [x] Add tests for pages
- [x] Add tests for recursive `export *`s
---
Closes#54038, closes#54286.
Adding a default app router not-found error page in production. We introduced a custom global not-found page if you have `not-found.js` file under app directory. Next.js will still routed you to default pages 404 if there's no routes matched when you don't have a custom `not-found.js`.
This PR creates a default layout (only having `html` and `body`) and will use the default not-found component as children to build a default 404 page for app router, and server will route to that page when there's any app router pages existed. This will also fix the hmr issue that when you hit a pathname doesn't exist, nextjs will compile `/_error` for you which is not expected, now we're using `/not-found` instead
Closes NEXT-1359
### What?
fix the paths for app pages with route groups (e. g. `(dashboard)`)
Closes WEB-1463
---------
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
## Implementation
Base on #54530, we're implementing a `optimize_barrel` transform to
optimize barrel files to only export the names we need. If the
transformed file isn't a "barrel file", we just re-export the names from
it without any transformation.
Take `lucide-react` as an example, with #54530 we are able to transform
```js
import { IceCream } from 'lucide-react'
```
to
```js
import { IceCream } from '__barrel_optimize__?names=IceCream!=!lucide-react?__barrel_optimize_noop__=IceCream'
```
And then, we apply that new request with a new Webpack module rule to
use the SWC loader with option `optimizeBarrelExports: ['IceCream']`,
which eventually got passed to this new `optimize_barrel` transform and
does the optimization.
## Notes
We'll have to add a new `getModularizeImportAliases` alias list to map
`lucide-react` to the ESM version, as we have the `['main', 'module']`
resolve order for the server compiler. Otherwise this optimization
doesn't work in that compiler.
There's no e2e test added because it's already covered by the
`modularize-imports` test as we removed the default `lucide-react`
transform rules and it still works.
We'll need to test other libs before migrating them to the new
`optimizePackageImports` option.
---
Closes#54571, closes#53605, closes#53789, closes#53894, closes
#54063.
This PR is a larger change to documentation to make the following
updates:
- Deconstructs [Server
Actions](https://nextjs.org/docs/app/building-your-application/data-fetching/server-actions)
into "Forms and Mutations" and an API reference
- Removes content in place of future React API documentation pages
- Removes outdated [Building
Forms](https://nextjs.org/docs/pages/building-your-application/data-fetching/building-forms)
docs from the Pages Router and adds conditional content for both routes
in "Forms and Mutations"
- Adds TypeScript code blocks to API Routes page, recommends Route
Handlers for isomorphic signatures.
- Updates `revalidatePath` and `revalidateTag` docs to have a Server
Actions example.
---------
Co-authored-by: Delba de Oliveira <32464864+delbaoliveira@users.noreply.github.com>
### What?
* add support for middleware manifest and edge adapter for pages API
routes
* improve the error reporting a tiny bit
### Why?
### How?
Closes WEB-1428
This is the first step to enable the automatic "modularize imports"
optimization for some libraries. It transforms named imports like
`import { A, B, C as F } from 'foo'` to a special loader string: `import
{ A, B, C as F } from "barrel-optimize-loader?names=A,B,C!foo"`.
In a follow-up PR we'll apply corresponding optimization with another
SWC transformer.
For the server compilation, we currently transpile the dynamic import
expression to `null` if `ssr` is disabled. However to make the Server
Actions layer work (as it can be created again from a Client Component),
we can't do that optimization.
This PR changes it to always keep that import expression when
`react_server_components` (App Router) is enabled, no matter which layer
it's on.
Closes#52672.
When `"use client"` directive appears after other statements, it should
be ignored instead of treat as client components. There's a bug inside
swc transform that we should mark the directives detection is "finished"
after other non string literals directives AST nodes are detected before
the first directive
x-ref:
https://github.com/vercel/next.js/pull/54358#discussion_r1300740950
Similar to #54004, this PR changes `private-next-rsc-action-validate`
and `private-next-rsc-action-client-wrapper` to export named values
instead of default values. In #54230 (currently broken), the Server
Action file was bundled via Vite/Rollup as an external dependency so
we're not doing the ESM interoperation correctly.
Closes#54230.
### What & Why
Add base path handling for the url in redirect error if the `basePath` is configured.
This is only break for server rendering case as the `basePath` is missing in the `Location` header. When running `next build`, everything is managed well with app router and base path on client side so it didn't break.
### How
Adding `basePath` if it's presented for `Location` header.
Update the `RenderOpts` type as basePath is already passed down in it, also update them for turbopack entries
Fixes#54163
Closes NEXT-1529
This fixes the compilation of `export { action as renamed }` syntax. Previously it's compiled as `export var action = ...` and with this fix, it will be `export var renamed = ...`.
Closes#54229.
### What?
Strip the relative path prefix (`_next/`) when generating the `PageLoaderAsset`. This is necessary because the page loader will internally use `__turbopack_load__`, which prepends the prefix back onto the path.
### Why?
Without this, we'd try loading `_next/_next/path/to/file.js`, because we'd prepend the prefix onto a path that already contains it.
### How?
When generating the page loader asset, we "proxy" the `OutputAsset` onto a path which has the prefix removed.
~~Depends on https://github.com/vercel/turbo/pull/5717~~
Closes WEB-1377
Note: depends on next Turbopack publish
https://github.com/vercel/turbo/pull/5487 exports a reusable `handle_issues` function for reporting issues and erroring when failing issues are encountered.
This uses it for `next build` with a failing severity level of error.
This PR changes the internal `createActionProxy` util from a default
export to a named export, as the default export could be problematic if
it's built without the "esModuleInterop" step.
---------
Co-authored-by: Balázs Orbán <info@balazsorban.com>
