This patch:
1. Refactor the routines used to compile and run an embedder
entrypoint. In JS land special handling for SEA is done
directly in main/embedding.js instead of clobbering the CJS
loader. Add warnings to remind users that currently the
require() in SEA bundled scripts only supports loading builtins.
2. Don't use the bundled SEA code cache when compiling CJS
loaded from disk, since in that case we are certainly not
compiling the code bundled into the SEA. Use a is_sea_main
flag in CompileFunctionForCJSLoader() (which replaces an unused
argument) to pass this into the C++ land - the code cache is
still read directly from C++ to avoid the overhead of
ArrayBuffer creation.
3. Move SEA loading code into
MaybeLoadSingleExecutableApplication() which calls
LoadEnvironment() with its own StartExecutionCallback().
This avoids more hidden switches in StartExecution() and
make them explicit. Also add some TODOs about how to support
ESM in embedded applications.
4. Add more comments
PR-URL: https://github.com/nodejs/node/pull/53573
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Unifies the CJS and ESM source map cache map with SourceMapCacheMap
and allows the CJS cache entries to be queried more efficiently with
a source url without iteration on an IterableWeakMap.
Add a test to verify that the CJS source map cache entry can be
reclaimed.
PR-URL: https://github.com/nodejs/node/pull/51711
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
This patch:
1. Adds ESM syntax detection to compileFunctionForCJSLoader()
for --experimental-detect-module and allow it to emit the
warning for how to load ESM when it's used to parse ESM as
CJS but detection is not enabled.
2. Moves the ESM detection of --experimental-detect-module for
the entrypoint from executeUserEntryPoint() into
Module.prototype._compile() and handle it directly in the
CJS loader so that the errors thrown during compilation *and
execution* during the loading of the entrypoint does not
need to be bubbled all the way up. If the entrypoint doesn't
parse as CJS, and detection is enabled, the CJS loader will
re-load the entrypoint as ESM on the spot asynchronously using
runEntryPointWithESMLoader() and cascadedLoader.import(). This
is fine for the entrypoint because unlike require(ESM) we don't
the namespace of the entrypoint synchronously, and can just
ignore the returned value. In this case process.mainModule is
reset to undefined as they are not available for ESM entrypoints.
3. Supports --experimental-detect-module for require(esm).
PR-URL: https://github.com/nodejs/node/pull/52047
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.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>
Previously we only had an internal assertion to ensure certain
code is executed before any user-provided CJS is run. This patch
adds another assertion for ESM.
Note that this internal state is not updated during source text
module execution via vm because to run any code via vm, some
user JS code must have already been executed anyway.
In addition this patch moves the states into internal/modules/helpers
to avoid circular dependencies. Also moves toggling the states to
true *right before* user code execution instead of after in case
we are half-way in the execution when internals try to check them.
PR-URL: https://github.com/nodejs/node/pull/51748
Reviewed-By: Antoine du Hamel <duhamelantoine1995@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>
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>
This patch:
- Builds the set of modules that can be required by users with/without
the `node:` prefix at snapshot building time. We only modify it when
`--expose-internals` but the default set is now in the snapshot. At
run time the CJS module loader only creates a frozen array out of it.
- `BuiltinModule.canBeRequiredWithoutScheme()` is now enough to
determine if an id can be required without `node:` without an
additional call to `BuiltinModule.canBeRequiredByUsers()`
- Replace the pending-to-deprecate methods on `Module` with an internal
implementation that only queries the CLI flags when being invoked.
So we can install these methods in the snapshot.
PR-URL: https://github.com/nodejs/node/pull/47194
Reviewed-By: Geoffrey Booth <webadmin@geoffreybooth.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>
This patch makes the top-level access to runtime states in the
CJS loader lazy, and move the side-effects into a
initializeCJS() function that gets called during pre-execution.
As a result the CJS loader 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>
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>
V8 already parses the source map magic comments. Currently, only scripts
and functions expose the parsed source map URLs. It is unnecessary to
parse the source map magic comments again when the parsed information is
available.
PR-URL: https://github.com/nodejs/node/pull/44798
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Jan Krems <jan.krems@gmail.com>
Joyee Cheung