Node.js 20 started throwing errors when `writeHead` is called twice on
a response. This might have already been invalid before but it wasn't throwing
on Node.js 18.
Compute the headers object and call `writeHead` once to avoid the issue.
Closes gh-5397
Updated tasks include:
- lint
- npmcopy
- build, minify, and process for distribution.
- new custom build command using yargs
- compare size of minified/gzip built files
- pretest scripts, including qunit-fixture, babel transpilation, and npmcopy
- node smoke tests
- promises aplus tests
- new watch task using `rollup.watch` directly
Also:
- upgraded husky and added the new lint command
- updated lint config to use new "flat" config format. See https://eslint.org/docs/latest/use/configure/configuration-files-new
- Temporarily disabled one lint rule until flat config is supported by eslint-plugin-import. See https://github.com/import-js/eslint-plugin-import/issues/2556
- committed package-lock.json
- updated all test scripts to use the new build
- added an express test server that uses middleware-mockserver (this can be used to run tests without karma)
- build-all-variants is now build:all
Close gh-5318
Summary of the changes:
* define the `exports` field in `package.json`; `jQuery` & `$` are also
exported as named exports in ESM builds now
* declare `"type": "module"` globally except for the `build` folder
* add the `--esm` option to `grunt custom`, generating jQuery as an ECMAScript
module into the `dist-module` folder
* expand `node_smoke_tests` to test the slim & ESM builds and their various
combinations; also, test both jQuery loaded via a path to the file as well
as from module specifiers that should be parsed via the `exports` feature
* add details about ESM usage to the release package README
* run `compare_size` on all built minified files; don't run it anymore on
unminified files where they don't provide lots of value
* remove the remove_map_comment task; SWC doesn't insert the
`//# sourceMappingURL=` pragma by default so there's nothing to strip
Fixes gh-4592
Closes gh-5255
