This PR introduces an improved developer experience when `next lint` is run for the first time.
### Current behavior
`eslint-config-next` is a required package that must be installed before proceeding with `next lint` or `next build`:
Although this has helped many developers start using the new ESLint config, this has also resulted in a few issues:
- Users are required to install the full config (`eslint-config-next`) even if they do not use it or use the Next.js plugin directly (`eslint-plugin-next`).
- #26348
- There's some confusion on why `eslint-config-next` needs to be installed or how it should be used instead of `eslint-plugin-next`.
- #26574
- #26475
- #26438
### New behavior
Instead of enforcing `eslint-config-next` as a required package, this PR prompts the user by asking what config they would like to start. This happens when `next lint` is run for the first time **and** if no ESLint configuration is detected in the application.
<img src="https://user-images.githubusercontent.com/12476932/124331177-e1668a80-db5c-11eb-8915-38d3dc20f5d4.gif" width="800" />
- The CLI will take care of installing `eslint` or `eslint-config-next` if either is not already installed
- Users now have the option to choose between a strict configuration (`next/core-web-vitals`) or just the base configuration (`next`)
- For users that decide to create their own ESLint configuration, or already have an existing one, **installing `eslint-config-next` will not be a requirement for `next lint` or `next build` to run**. A warning message will just show if the Next.js ESLint plugin is not detected in an ESLint config.
<img width="682" alt="Screen Shot 2021-06-25 at 3 02 12 PM" src="https://user-images.githubusercontent.com/12476932/123473329-6cc4a680-d5c6-11eb-9a57-d5c0b89a2732.png">
---
In addition, this PR also:
- Fixes#26348
- Updates documentation to make it more clear what approach to take for new and existing ESLint configurations
## Bug
- [x] Related issues linked using `fixes #number`
- [x] Integration tests added
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
## Documentation / Examples
- [ ] Make sure the linting passes
Fixes: #23716
This pull request **temporarily** removes ESLint, as it was not landed in accordance with our standard experimental policies. We are fully committed to landing this change again.
This is being reverted because:
- Next.js has very strict goals for its install size. This feature resulted in adding over 17MB, or a 43.6% increase.
- The feature was not first landed under the `experimental` key in `next.config.js`, rather, it was added under the stable namespace (top-level)
- Using the feature doesn't do a "guided setup" like TypeScript, it should ask you to "bring your own" dependencies for ESLint
- It uses a undesirable ESLint plugin name: `plugin:@next/next/recommended`. This should read out as strictly `next`, or as short as we can get it.
- Does not provide actionable warnings (missing link to resolve issue)
- Does not follow appropriate console output styling. We need to revisit how these are presented.
To re-land this, we need to ensure the following minimums are met:
- Very minor change in install size
- Fully experimental (i.e. flagged) with warnings
- Finalized package name and configuration shape, preferably so we can do ` { extends: 'next' } `.
For #22228
This PR:
- Adds ESLint to toolchain
- Included by default for builds (`next build`)
- Can be enabled for development (`next dev`)
- Custom formatter built for output
- Adds appropriate tests
- Adds two documentation pages
* Get all modules included in build
* Add tests
* Get all modules contained per entry chunk
* Sort files
* Add specialized page entry to manifest
* Split manifest into pages and chunks key
* Update test
* Use relative paths to build directory
* Update test
* Add build manifest
* Split out css since they don’t have exact name
* Remove pages map
* Fix locations test
* Re-run tests
* Get consistent open ports
* Fix static tests
* Add comment about Cache-Control header
* Removed combine-assets-plugin, since its very broken
* Bundle everything into app.js on production build
* Clean up
* Removed app.js from server routes
* Renamed app.js -> main.js and removed commons from loading
* Remove commons and react CommonChunks
* Removed the commons route
* Killing the entire build-stats hack for app.js
* Removed unused md5-file package
* Dump address.
* Use zero as the port.
* Limit test cases.
* throw address.
* Fail a specific error.
* Set a port manually.
* Make sure jest is working properly.
* Set the jest timeout time to 5 min.
* Run the actual test
* Run all production tests on Travis.
* Set the Jest default timeout to 5 min for all integration tests.
* Remove production only testing.
* Remove unwanted console.log
* Remove the addition number from test case
* Set the static export test jest timeout to 5 min.
* Run tests again if they failed once.
* Update references to `.next`
* Remove console logs and extraneous semi colons
* Remove lint errors
* Update references to .next and update docs
* Update options from nested to flat with `distDir`
* Add integration tests, and update `.gitignore`
* Rename integration folder to dist-dir to match standards
