In most browsers, clicking links with the Alt key has a special behavior, for example, Chrome downloads the target resource. As with other modifier keys, the router should stop the original navigation to avoid preventing the browser’s default behavior.
When users click a link while holding the Alt key together, the browsers behave as follows.
Windows 10:
| Browser | Behavior |
|:-----------|:--------------------------------------------|
| Chrome 84 | Download the target resource |
| Firefox 79 | Prevent navigation and therefore do nothing |
| Edge 84 | Download the target resource |
| IE 11 | No impact |
macOS Catalina:
| Browser | Behavior |
|:-----------|:--------------------------------------------|
| Chrome 84 | Download the target resource |
| Firefox 79 | Prevent navigation and therefore do nothing |
| Safari 13 | Download the target resource |
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)
Replace `url.parse` and `url.resolve` logic with whatwg `URL`, Bring in a customized `format` function to handle the node url objects that can be passed to router methods. This eliminates the need for `url` (and thus `native-url`) in core. Looks like it shaves off about 2.5Kb, according to the `size-limits` integration tests.
Currently following links are broken when using `basePath`:
```jsx
// pages/hello.js
<Link href="#hashlink">
<a id="hashlink">Hash Link</a>
</Link>
```
with `basePath: '/docs'`, this will navigate to `/docs/docs/hello#hashlink` instead of `/docs/hello#hashlink`
I have a further optimization that builds on this branch that removes `url.parse` and `url.resolve` in favor for `new URL()` in router and link. Will PR when this gets merged.
Convert `Link` to a function component. Prefetch logic and memoized url formatting now meshes nicely with React hooks. Class methods were hoisted to module scope to preserve performance characteristics.
* avoid pulling code in the bundle for `trailingSlash` logic when it's not enabled
* avoid cloning the url an extra time if normalizing the path doesn't change it
As discussed, this streamlines the handling for `basePath` to not automatically strip and add the `basePath` when provided to `next/link` or `router.push/replace` and only automatically adds the `basePath` and when it is manually provided it will cause a 404 which ensures `href` still matches to the pages directory 1-to-1.
This also adds additional test cases that we discussed to ensure this behavior is working as intended
---
Fixes#13902
Was going through _document and noticed some variable shadowing going on. Added a rule for it to our eslint configuration and went through all warnings with @Timer.
* Add basePath in link component and add/remove it consistently
* Update to not use regex for delBasePath
* Expose addBasePath as router method
* Revert "Expose addBasePath as router method"
This reverts commit 40fed596195c6affabf837e42d472452768e13a3.
* Expose basePath as router field
* Apply suggestion
* Expose basePath as router field
* remove un-used vars
* Update externals
* Apply lint fix
* Update size-limit test
* Update prefetch
* Remove ts-ignore where possible
And replace by typecasts
* More accurate types
* bend cliententries in a correct shape earlier on
* comment becomes unnecessary
* add webpack overload to allow for the next.js use case
* Avoid changing public interface
Co-authored-by: Joe Haddad <timer150@gmail.com>
* Add warning for bad href being passed to router
* Apply suggestions from code review
Co-Authored-By: Joe Haddad <timer150@gmail.com>
* Inline invalidHref for better code elimination
* Use intersection observer to preload
links that are in viewport
* Clean up names
* Check for window before returning observer
* update check for IntersectionObserver
* Remove duplicate IntersectionObserver checks
* Add test for prefetching links in viewport