Symbol properties are typically more GC-efficient than using WeakMaps,
since WeakMap requires ephemeron GC. `module[kModuleExportNames]`
would be easier to read than `importedCJSCache.get(module).exportNames`
as well.
PR-URL: https://github.com/nodejs/node/pull/52095
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
This patch disallows CJS <-> ESM edges when they come from
require(esm) requested in ESM evalaution.
Drive-by: don't reuse the cache for imported CJS modules to stash
source code of required ESM because the former is also used for
cycle detection.
PR-URL: https://github.com/nodejs/node/pull/52264
Fixes: https://github.com/nodejs/node/issues/52145
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
This refactors the code that compiles SourceTextModule for the
built-in ESM loader to use a common routine so that it's easier
to customize cache handling for the ESM loader. In addition
this introduces a common symbol for import.meta and import()
so that we don't need to create additional closures as handlers,
since we can get all the information we need from the V8 callback
already. This should reduce the memory footprint of ESM as well.
PR-URL: https://github.com/nodejs/node/pull/52291
Refs: https://github.com/nodejs/node/issues/47472
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Stephen Belanger <admin@stephenbelanger.com>
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>
So that we can use it to handle code caching in a central place.
Drive-by: use per-isolate persistent strings for the parameters
and mark GetHostDefinedOptions() since it's only used in one
compilation unit
PR-URL: https://github.com/nodejs/node/pull/52016
Refs: https://github.com/nodejs/node/issues/47472
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Split the `internal/process/esm_loader` file which contains the
singleton cascaded loader:
- The the singleton cascaded loader now directly resides in
`internal/modules/esm/loader`, where the constructor also lives.
This file is the root of most circular dependency of ESM code,
(because components of the loader need the singleton itself),
so this makes the dependency more obvious. Added comments about
loading it lazily to avoid circular dependency.
- The getter to the cascaded loader is also turned into a method
to make the side effect explicit.
- The sequence of `loadESM()` and `handleMainPromise` is now merged
together into `runEntryPointWithESMLoader()` in
`internal/modules/run_main` because this is intended to run entry
points with the ESM loader and not just any module.
- Documents how top-level await is handled.
PR-URL: https://github.com/nodejs/node/pull/51999
Fixes: https://github.com/nodejs/node/issues/42868
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
This patch adds support for using
`vm.constants.USE_MAIN_CONTEXT_DEFAULT_LOADER` as
`importModuleDynamically` in all APIs that take the option
except `vm.SourceTextModule`. This allows users to have a shortcut
to support dynamic import() in the compiled code without missing
the compilation cache if they don't need customization of the
loading process. We emit an experimental warning when the
`import()` is actually handled by the default loader through
this option instead of requiring `--experimental-vm-modules`.
In addition this refactors the documentation for
`importModuleDynamically` and adds a dedicated section for it
with examples.
`vm.SourceTextModule` is not supported in this patch because
it needs additional refactoring to handle `initializeImportMeta`,
which can be done in a follow-up.
PR-URL: https://github.com/nodejs/node/pull/51244
Fixes: https://github.com/nodejs/node/issues/51154
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
This puts it together with the cjsParseCache and reduces the
circular dependency on the singleton loader, which is the
only place where this cache is stored.
Drive-by: remove always-false module status check because there's
no longer a local module variable after
https://github.com/nodejs/node/pull/34605 which is now invalid
leftover code at this point and only doesn't throw because
we happen to have a top-level variable called module.
PR-URL: https://github.com/nodejs/node/pull/51157
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/51033
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/50466
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
When using the Modules Customization Hooks API to load CommonJS modules,
we want to support the returned value of `defaultLoad` which must be
nullish to preserve backward compatibility. This can be achieved by
fetching the source from the translator.
PR-URL: https://github.com/nodejs/node/pull/50825
Fixes: https://github.com/nodejs/node/issues/50435
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
PR-URL: https://github.com/nodejs/node/pull/50127
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Instead of using the public versions of the vm APIs internally,
use the internal versions so that we can skip unnecessary
argument validation.
The public versions would need special care to the generation
of host-defined options to hit the isolate compilation cache
when imporModuleDynamically isn't used, while internally it's
almost always used, so this allows us to handle the host-defined
options separately.
PR-URL: https://github.com/nodejs/node/pull/50137
Refs: https://github.com/nodejs/node/issues/35375
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
The old import assertions proposal has been
renamed to "import attributes" with the follwing major changes:
1. The keyword is now `with` instead of `assert`.
2. Unknown assertions cause an error rather than being ignored,
This commit updates the documentation to encourage folks to use the new
syntax, and add aliases for module customization hooks.
PR-URL: https://github.com/nodejs/node/pull/50140
Fixes: https://github.com/nodejs/node/issues/50134
Refs: 159c82c5e6
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Previously when managing the importModuleDynamically callback of
vm.compileFunction(), we use an ID number as the host defined option
and maintain a per-Environment ID -> CompiledFnEntry map to retain
the top-level referrer function returned by vm.compileFunction() in
order to pass it back to the callback, but it would leak because with
how we used v8::Persistent to maintain this reference, V8 would not
be able to understand the cycle and would just think that the
CompiledFnEntry was supposed to live forever. We made an attempt
to make that reference known to V8 by making the CompiledFnEntry weak
and using a private symbol to make CompiledFnEntry strongly
references the top-level referrer function in
https://github.com/nodejs/node/pull/46785, but that turned out to be
unsound, because the there's no guarantee that the top-level function
must be alive while import() can still be initiated from that
function, since V8 could discard the top-level function and only keep
inner functions alive, so relying on the top-level function to keep
the CompiledFnEntry alive could result in use-after-free which caused
a revert of that fix.
With this patch we use a symbol in the host defined options instead of
a number, because with the stage-3 symbol-as-weakmap-keys proposal
we could directly use that symbol to keep the referrer alive using a
WeakMap. As a bonus this also keeps the other kinds of referrers
alive as long as import() can still be initiated from that
Script/Module, so this also fixes the long-standing crash caused by
vm.Script being GC'ed too early when its importModuleDynamically
callback still needs it.
PR-URL: https://github.com/nodejs/node/pull/48510
Refs: https://github.com/nodejs/node/issues/44211
Refs: https://github.com/nodejs/node/issues/42080
Refs: https://github.com/nodejs/node/issues/47096
Refs: https://github.com/nodejs/node/issues/43205
Refs: https://github.com/nodejs/node/issues/38695
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Stephen Belanger <admin@stephenbelanger.com>
PR-URL: https://github.com/nodejs/node/pull/46305
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
This moves the following utils into modules/esm/utils.js:
- Code related to default conditions
- The callbackMap (which is now created in the module instead of
hanging off the module_wrap binding, since the C++ land
does not need it).
- Per-isolate module callbacks
These are self-contained code that can be included into the
built-in snapshot.
PR-URL: https://github.com/nodejs/node/pull/45849
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
The helpers are actually shared by the two loaders, so move them
under modules/ directly.
PR-URL: https://github.com/nodejs/node/pull/45849
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.
Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).
PR-URL: https://github.com/nodejs/node/pull/45659
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
The term "native module" dates back to some of the oldest code
in the code base. Within the context of Node.js core it usually
refers to modules that are native to Node.js (e.g. fs, http),
but it can cause confusion for people who don't work on this
part of the code base, as "native module" can also refer to
native addons - which is even the case in some of the API
docs and error messages.
This patch tries to make the usage of these terms more consistent.
Now within the context of Node.js core:
- JavaScript scripts that are built-in to Node.js are now referred
to as "built-in(s)". If they are available as modules,
they can also be referred to as "built-in module(s)".
- Dynamically-linked shared objects that are loaded into
the Node.js processes are referred to as "addons".
We will try to avoid using the term "native modules" because it could
be ambiguous.
Changes in this patch:
File names:
- node_native_module.h -> node_builtins.h,
- node_native_module.cc -> node_builtins.cc
C++ binding names:
- `native_module` -> `builtins`
`node::Environment`:
- `native_modules_without_cache` -> `builtins_without_cache`
- `native_modules_with_cache` -> `builtins_with_cache`
- `native_modules_in_snapshot` -> `builtins_in_cache`
- `native_module_require` -> `builtin_module_require`
`node::EnvSerializeInfo`:
- `native_modules` -> `builtins
`node::native_module::NativeModuleLoader`:
- `native_module` namespace -> `builtins` namespace
- `NativeModuleLoader` -> `BuiltinLoader`
- `NativeModuleRecordMap` -> `BuiltinSourceMap`
- `NativeModuleCacheMap` -> `BuiltinCodeCacheMap`
- `ModuleIds` -> `BuiltinIds`
- `ModuleCategories` -> `BuiltinCategories`
- `LoadBuiltinModuleSource` -> `LoadBuiltinSource`
`loader.js`:
- `NativeModule` -> `BuiltinModule` (the `NativeModule` name used in
`process.moduleLoadList` is kept for compatibility)
And other clarifications in the documentation and comments.
PR-URL: https://github.com/nodejs/node/pull/44135
Fixes: https://github.com/nodejs/node/issues/44036
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: Mohammed Keyvanzadeh <mohammadkeyvanzade94@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Jan Krems <jan.krems@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/43612
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Mohammed Keyvanzadeh <mohammadkeyvanzade94@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/43164
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
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>
Fixes: https://github.com/nodejs/node/issues/36098
Co-authored-by: Antoine du Hamel <duhamelantoine1995@gmail.com>
Co-authored-by: Guy Bedford <guybedford@gmail.com>
Co-authored-by: Darshan Sen <raisinten@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/37246
Reviewed-By: Bradley Farias <bradley.meck@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
It is guaranteed that V8 throws a syntax error when `import` or `export`
is used outside of ESM.
Fixes: https://github.com/nodejs/node/issues/35687
PR-URL: https://github.com/nodejs/node/pull/35691
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>