This PR Fixes#4920
So the problem is that when a next.js application is built on windows, the `pages-manifest.json` file is created with backslashes. If this built application is deployed to a linux hosting enviroment, the server will fail when trying to load the modules.
```
Error: Cannot find module '/user_code/next/server/bundles\pages\index.js
```
My simple solution is to modify the `pages-manifest.json` to always use linux separator (`/`), then also
modify `server/require.js` to, when requiring page, replace any separator (`\` or `/`) with current platform-specific file separator (`require('path').sep`).
The fix in `server/require.js` would be sufficient, but my opinion is that having some cross-platform consistency is nice.
This change was tested by bulding an application in windows and running it in linux and windows, aswell as building an application in linux and running it in linux and windows. The related tests was also run.
# Conflicts:
# test/integration/production/test/index.test.js
* Move send-html function and rewrite in typescript
* Move getPageFiles and convert to ts
* Move getPageFiles and convert to ts (#5841)
* Move getPageFiles and convert to ts
# Conflicts:
# packages/next-server/server/render.js
* Fix unit tests
We don't have to check if the file already exists here, since it's always in production mode (dev overrides the readBuildId method to always be `development`) If the file is not found (error is thrown) we check if the file exists. If not we throw a helpful error. In other cases we throw the original error.
Fixes#3705Fixes#4656
- No longer automatically dedupe certain tags. Only the ones we know are *never* going to be duplicate like charSet, title etc.
- Fix `key=""` behavior, making sure that if a unique key is provided tags are deduped based on that.
For example:
```jsx
<meta property='fb:pages' content='one'>
<meta property='fb:pages' content='two'>
```
Would currently cause
```jsx
<meta property='fb:pages' content='two'>
```
### After this change:
```jsx
<meta property='fb:pages' content='one'>
<meta property='fb:pages' content='two'>
```
Then if you use next/head multiple times / want to be able to override:
```jsx
<meta property='fb:pages' content='one' key="not-unique-key">
<meta property='fb:pages' content='two' key="not-unique-key">
```
Would cause:
```jsx
<meta property='fb:pages' content='two'>
```
As `key` gets deduped correctly after this PR, similar to how React itself works.
- Replaces taskr-babel with taskr-typescript for the `next` package
- Makes sure Node 8+ is used, no unneeded transpilation
- Compile Next.js client side files through babel the same way pages are
- Compile Next.js client side files to esmodules, not commonjs, so that tree shaking works.
- Move error-debug.js out of next-server as it's only used/require in development
- Drop ansi-html as dependency from next-server
- Make next/link esmodule (for tree-shaking)
- Make next/router esmodule (for tree-shaking)
- add typescript compilation to next-server
- Remove last remains of Flow
- Move hoist-non-react-statics to next, out of next-server
- Move htmlescape to next, out of next-server
- Remove runtime-corejs2 from next-server
