This patch adds `require()` support for synchronous ESM graphs under
the flag `--experimental-require-module`
This is based on the the following design aspect of ESM:
- The resolution can be synchronous (up to the host)
- The evaluation of a synchronous graph (without top-level await) is
also synchronous, and, by the time the module graph is instantiated
(before evaluation starts), this is is already known.
If `--experimental-require-module` is enabled, and the ECMAScript
module being loaded by `require()` meets the following requirements:
- Explicitly marked as an ES module with a `"type": "module"` field in
the closest package.json or a `.mjs` extension.
- Fully synchronous (contains no top-level `await`).
`require()` will load the requested module as an ES Module, and return
the module name space object. In this case it is similar to dynamic
`import()` but is run synchronously and returns the name space object
directly.
```mjs
// point.mjs
export function distance(a, b) {
return (b.x - a.x) ** 2 + (b.y - a.y) ** 2;
}
class Point {
constructor(x, y) { this.x = x; this.y = y; }
}
export default Point;
```
```cjs
const required = require('./point.mjs');
// [Module: null prototype] {
// default: [class Point],
// distance: [Function: distance]
// }
console.log(required);
(async () => {
const imported = await import('./point.mjs');
console.log(imported === required); // true
})();
```
If the module being `require()`'d contains top-level `await`, or the
module graph it `import`s contains top-level `await`,
[`ERR_REQUIRE_ASYNC_MODULE`][] will be thrown. In this case, users
should load the asynchronous module using `import()`.
If `--experimental-print-required-tla` is enabled, instead of throwing
`ERR_REQUIRE_ASYNC_MODULE` before evaluation, Node.js will evaluate the
module, try to locate the top-level awaits, and print their location to
help users fix them.
PR-URL: https://github.com/nodejs/node/pull/51977
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
PR-URL: https://github.com/nodejs/node/pull/40785
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Bradley Farias <bradley.meck@gmail.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Remove V8 flag for import assertions, enabling support for the syntax;
require the import assertion syntax for imports of JSON.
Support import assertions in user loaders.
Use both resolved module URL and import assertion type as the key for
caching modules.
Co-authored-by: Geoffrey Booth <webadmin@geoffreybooth.com>
PR-URL: https://github.com/nodejs/node/pull/40250
Reviewed-By: Bradley Farias <bradley.meck@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
doc: update ESM hook examples
esm: fix unsafe primordial
doc: fix ESM example linting
esm: allow source of type ArrayBuffer
doc: update ESM hook changelog to include resolve format
esm: allow all ArrayBuffers and TypedArrays for load hook source
doc: tidy code & API docs
doc: convert ESM source table header from Title Case to Sentence case
doc: add detailed explanation for getPackageType
esm: add caveat that ESMLoader::import() must NOT be renamed
esm: tidy code declaration of getFormat protocolHandlers
doc: correct ESM doc link (bad conflict resolution)
doc: update ESM hook limitation for CJS
esm: tweak preload description
doc: update ESM getPackageType() example explanation
PR-URL: https://github.com/nodejs/node/pull/37468
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Bradley Farias <bradley.meck@gmail.com>
Reviewed-By: Geoffrey Booth <webmaster@geoffreybooth.com>
Since the URL and URLSearchParams classes are available in the
global object, there is no need to require them from 'url'.
PR-URL: https://github.com/nodejs/node/pull/36927
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
This completely refactors the `expectsError` behavior: so far it's
almost identical to `assert.throws(fn, object)` in case it was used
with a function as first argument. It had a magical property check
that allowed to verify a functions `type` in case `type` was passed
used in the validation object. This pattern is now completely removed
and `assert.throws()` should be used instead.
The main intent for `common.expectsError()` is to verify error cases
for callback based APIs. This is now more flexible by accepting all
validation possibilites that `assert.throws()` accepts as well. No
magical properties exist anymore. This reduces surprising behavior
for developers who are not used to the Node.js core code base.
This has the side effect that `common` is used significantly less
frequent.
PR-URL: https://github.com/nodejs/node/pull/31092
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
ERR_INVALID_ARG_TYPE is the most common error used throughout the
code base. This improves the error message by providing more details
to the user and by indicating more precisely which values are allowed
ones and which ones are not.
It adds the actual input to the error message in case it's a primitive.
If it's a class instance, it'll print the class name instead of
"object" and "falsy" or similar entries are not named "type" anymore.
PR-URL: https://github.com/nodejs/node/pull/29675
Reviewed-By: Rich Trott <rtrott@gmail.com>
This PR updates the current `--experimental-modules` implementation
based on the work of the modules team and reflects Phase 2 of our
new modules plan.
The largest differences from the current implementation include
* `packge.type` which can be either `module` or `commonjs`
- `type: "commonjs"`:
- `.js` is parsed as commonjs
- default for entry point without an extension is commonjs
- `type: "module"`:
- `.js` is parsed as esm
- does not support loading JSON or Native Module by default
- default for entry point without an extension is esm
* `--entry-type=[mode]`
- allows you set the type on entry point.
* A new file extension `.cjs`.
- this is specifically to support importing commonjs in the
`module` mode.
- this is only in the esm loader, the commonjs loader remains
untouched, but the extension will work in the old loader if you use
the full file path.
* `--es-module-specifier-resolution=[type]`
- options are `explicit` (default) and `node`
- by default our loader will not allow for optional extensions in
the import, the path for a module must include the extension if
there is one
- by default our loader will not allow for importing directories that
have an index file
- developers can use `--es-module-specifier-resolution=node` to
enable the commonjs specifier resolution algorithm
- This is not a “feature” but rather an implementation for
experimentation. It is expected to change before the flag is
removed
* `--experimental-json-loader`
- the only way to import json when `"type": "module"`
- when enable all `import 'thing.json'` will go through the
experimental loader independent of mode
- based on https://github.com/whatwg/html/issues/4315
* You can use `package.main` to set an entry point for a module
- the file extensions used in main will be resolved based on the
`type` of the module
Refs: https://github.com/nodejs/modules/blob/master/doc/plan-for-new-modules-implementation.md
Refs: https://github.com/GeoffreyBooth/node-import-file-specifier-resolution-proposal
Refs: https://github.com/nodejs/modules/pull/180
Refs: https://github.com/nodejs/ecmascript-modules/pull/6
Refs: https://github.com/nodejs/ecmascript-modules/pull/12
Refs: https://github.com/nodejs/ecmascript-modules/pull/28
Refs: https://github.com/nodejs/modules/issues/255
Refs: https://github.com/whatwg/html/issues/4315
Refs: https://github.com/w3c/webcomponents/issues/770
Co-authored-by: Myles Borins <MylesBorins@google.com>
Co-authored-by: John-David Dalton <john.david.dalton@gmail.com>
Co-authored-by: Evan Plaice <evanplaice@gmail.com>
Co-authored-by: Geoffrey Booth <webmaster@geoffreybooth.com>
Co-authored-by: Michaël Zasso <targos@protonmail.com>
PR-URL: https://github.com/nodejs/node/pull/26745
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Ben Coe <bencoe@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
This commit renames all JavaScript source files in lib to lower
snake_case.
PR-URL: https://github.com/nodejs/node/pull/19556
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
This makes a effort to make sure all of these errors will actually
also show the received input.
On top of that it refactors a few tests for better maintainability.
It will also change the returned type to always be a simple typeof
instead of special handling null.
PR-URL: https://github.com/nodejs/node/pull/19445
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Add test for ModuleMap set with ModuleJob but bad url.
PR-URL: https://github.com/nodejs/node/pull/16045
Reviewed-By: Stephen Belanger <admin@stephenbelanger.com>
Reviewed-By: Bradley Farias <bradley.meck@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>