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GeezerVison is showing github.com — esm: js-string Wasm builtins in ESM Integration · nodejs/node@71bb6cd

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  • doc/api
    • esm.md
  • lib/internal/modules/esm
    • translators.js
  • test
    • es-module
      • test-esm-wasm.mjs
    • fixtures/es-modules
      • invalid-export-name-wasm-js.wasm
      • invalid-export-name-wasm-js.wat
      • invalid-export-name.wasm
      • invalid-export-name.wat
      • invalid-import-module.wasm
      • invalid-import-module.wat
      • invalid-import-name-wasm-js.wasm
      • invalid-import-name-wasm-js.wat
      • invalid-import-name.wasm
      • invalid-import-name.wat
      • js-string-builtins.wasm
      • js-string-builtins.wat
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‎doc/api/esm.md‎

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+69Lines changed: 69 additions & 0 deletions
  • Display the source diff
  • Display the rich diff
Original file line numberDiff line numberDiff line change
@@ -760,6 +760,74 @@ const dynamicLibrary = await import.source('./library.wasm');
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const instance = await WebAssembly.instantiate(dynamicLibrary, importObject);
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```
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### JavaScript String Builtins
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<!-- YAML
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added: REPLACEME
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-->
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When importing WebAssembly modules, the
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[WebAssembly JS String Builtins Proposal][] is automatically enabled through the
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ESM Integration. This allows WebAssembly modules to directly use efficient
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compile-time string builtins from the `wasm:js-string` namespace.
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For example, the following Wasm module exports a string `getLength` function using
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the `wasm:js-string` `length` builtin:
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```text
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(module
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;; Compile-time import of the string length builtin.
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(import "wasm:js-string" "length" (func $string_length (param externref) (result i32)))
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;; Define getLength, taking a JS value parameter assumed to be a string,
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;; calling string length on it and returning the result.
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(func $getLength (param $str externref) (result i32)
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local.get $str
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call $string_length
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)
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;; Export the getLength function.
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(export "getLength" (func $get_length))
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)
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```
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```js
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import { getLength } from './string-len.wasm';
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getLength('foo'); // Returns 3.
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```
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Wasm builtins are compile-time imports that are linked during module compilation
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rather than during instantiation. They do not behave like normal module graph
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imports and they cannot be inspected via `WebAssembly.Module.imports(mod)`
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or virtualized unless recompiling the module using the direct
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`WebAssembly.compile` API with string builtins disabled.
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Importing a module in the source phase before it has been instantiated will also
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use the compile-time builtins automatically:
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```js
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import source mod from './string-len.wasm';
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const { exports: { getLength } } = await WebAssembly.instantiate(mod, {});
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getLength('foo'); // Also returns 3.
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```
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### Reserved Wasm Namespaces
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<!-- YAML
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added: REPLACEME
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-->
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When importing WebAssembly modules through the ESM Integration, they cannot use
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import module names or import/export names that start with reserved prefixes:
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* `wasm-js:` - reserved in all module import names, module names and export
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names.
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* `wasm:` - reserved in module import names and export names (imported module
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names are allowed in order to support future builtin polyfills).
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Importing a module using the above reserved names will throw a
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`WebAssembly.LinkError`.
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763831
<i id="esm_experimental_top_level_await"></i>
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## Top-level `await`
@@ -1202,6 +1270,7 @@ resolution for ESM specifiers is [commonjs-extension-resolution-loader][].
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[Source Phase Imports]: https://github.com/tc39/proposal-source-phase-imports
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[Terminology]: #terminology
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[URL]: https://url.spec.whatwg.org/
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[WebAssembly JS String Builtins Proposal]: https://github.com/WebAssembly/js-string-builtins
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[`"exports"`]: packages.md#exports
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[`"type"`]: packages.md#type
12071276
[`--input-type`]: cli.md#--input-typetype
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‎lib/internal/modules/esm/translators.js‎

Copy file name to clipboardExpand all lines: lib/internal/modules/esm/translators.js
+14-1Lines changed: 14 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -506,7 +506,10 @@ translators.set('wasm', async function(url, source) {
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// TODO(joyeecheung): implement a translator that just uses
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// compiled = new WebAssembly.Module(source) to compile it
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// synchronously.
509-
compiled = await WebAssembly.compile(source);
509+
compiled = await WebAssembly.compile(source, {
510+
// The ESM Integration auto-enables Wasm JS builtins by default when available.
511+
builtins: ['js-string'],
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});
510513
} catch (err) {
511514
err.message = errPath(url) + ': ' + err.message;
512515
throw err;
@@ -518,6 +521,13 @@ translators.set('wasm', async function(url, source) {
518521
if (impt.kind === 'global') {
519522
ArrayPrototypePush(wasmGlobalImports, impt);
520523
}
524+
// Prefix reservations per https://webassembly.github.io/esm-integration/js-api/index.html#parse-a-webassembly-module.
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if (impt.module.startsWith('wasm-js:')) {
526+
throw new WebAssembly.LinkError(`Invalid Wasm import "${impt.module}" in ${url}`);
527+
}
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if (impt.name.startsWith('wasm:') || impt.name.startsWith('wasm-js:')) {
529+
throw new WebAssembly.LinkError(`Invalid Wasm import name "${impt.module}" in ${url}`);
530+
}
521531
importsList.add(impt.module);
522532
}
523533

@@ -527,6 +537,9 @@ translators.set('wasm', async function(url, source) {
527537
if (expt.kind === 'global') {
528538
wasmGlobalExports.add(expt.name);
529539
}
540+
if (expt.name.startsWith('wasm:') || expt.name.startsWith('wasm-js:')) {
541+
throw new WebAssembly.LinkError(`Invalid Wasm export name "${expt.name}" in ${url}`);
542+
}
530543
exportsList.add(expt.name);
531544
}
532545

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‎test/es-module/test-esm-wasm.mjs‎

Copy file name to clipboardExpand all lines: test/es-module/test-esm-wasm.mjs
+91Lines changed: 91 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -403,4 +403,95 @@ describe('ESM: WASM modules', { concurrency: !process.env.TEST_PARALLEL }, () =>
403403
strictEqual(stdout, '');
404404
notStrictEqual(code, 0);
405405
});
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it('should reject wasm: import names', async () => {
408+
const { code, stderr, stdout } = await spawnPromisified(execPath, [
409+
'--no-warnings',
410+
'--experimental-wasm-modules',
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'--input-type=module',
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'--eval',
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`import(${JSON.stringify(fixtures.fileURL('es-modules/invalid-import-name.wasm'))})`,
414+
]);
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match(stderr, /Invalid Wasm import name/);
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strictEqual(stdout, '');
418+
notStrictEqual(code, 0);
419+
});
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it('should reject wasm-js: import names', async () => {
422+
const { code, stderr, stdout } = await spawnPromisified(execPath, [
423+
'--no-warnings',
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'--experimental-wasm-modules',
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'--input-type=module',
426+
'--eval',
427+
`import(${JSON.stringify(fixtures.fileURL('es-modules/invalid-import-name-wasm-js.wasm'))})`,
428+
]);
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match(stderr, /Invalid Wasm import name/);
431+
strictEqual(stdout, '');
432+
notStrictEqual(code, 0);
433+
});
434+
435+
it('should reject wasm-js: import module names', async () => {
436+
const { code, stderr, stdout } = await spawnPromisified(execPath, [
437+
'--no-warnings',
438+
'--experimental-wasm-modules',
439+
'--input-type=module',
440+
'--eval',
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`import(${JSON.stringify(fixtures.fileURL('es-modules/invalid-import-module.wasm'))})`,
442+
]);
443+
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match(stderr, /Invalid Wasm import/);
445+
strictEqual(stdout, '');
446+
notStrictEqual(code, 0);
447+
});
448+
449+
it('should reject wasm: export names', async () => {
450+
const { code, stderr, stdout } = await spawnPromisified(execPath, [
451+
'--no-warnings',
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'--experimental-wasm-modules',
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'--input-type=module',
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'--eval',
455+
`import(${JSON.stringify(fixtures.fileURL('es-modules/invalid-export-name.wasm'))})`,
456+
]);
457+
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match(stderr, /Invalid Wasm export/);
459+
strictEqual(stdout, '');
460+
notStrictEqual(code, 0);
461+
});
462+
463+
it('should reject wasm-js: export names', async () => {
464+
const { code, stderr, stdout } = await spawnPromisified(execPath, [
465+
'--no-warnings',
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'--experimental-wasm-modules',
467+
'--input-type=module',
468+
'--eval',
469+
`import(${JSON.stringify(fixtures.fileURL('es-modules/invalid-export-name-wasm-js.wasm'))})`,
470+
]);
471+
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match(stderr, /Invalid Wasm export/);
473+
strictEqual(stdout, '');
474+
notStrictEqual(code, 0);
475+
});
476+
477+
it('should support js-string builtins', async () => {
478+
const { code, stderr, stdout } = await spawnPromisified(execPath, [
479+
'--no-warnings',
480+
'--experimental-wasm-modules',
481+
'--input-type=module',
482+
'--eval',
483+
[
484+
'import { strictEqual } from "node:assert";',
485+
`import * as wasmExports from ${JSON.stringify(fixtures.fileURL('es-modules/js-string-builtins.wasm'))};`,
486+
'strictEqual(wasmExports.getLength("hello"), 5);',
487+
'strictEqual(wasmExports.concatStrings("hello", " world"), "hello world");',
488+
'strictEqual(wasmExports.compareStrings("test", "test"), 1);',
489+
'strictEqual(wasmExports.compareStrings("test", "different"), 0);',
490+
].join('\n'),
491+
]);
492+
493+
strictEqual(stderr, '');
494+
strictEqual(stdout, '');
495+
strictEqual(code, 0);
496+
});
406497
});
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‎test/fixtures/es-modules/invalid-export-name-wasm-js.wasm‎

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‎test/fixtures/es-modules/invalid-export-name-wasm-js.wat‎

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+7Lines changed: 7 additions & 0 deletions
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@@ -0,0 +1,7 @@
1+
;; Test WASM module with invalid export name starting with 'wasm-js:'
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(module
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(func $test (result i32)
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i32.const 42
5+
)
6+
(export "wasm-js:invalid" (func $test))
7+
)
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‎test/fixtures/es-modules/invalid-export-name.wasm‎

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‎test/fixtures/es-modules/invalid-export-name.wat‎

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+7Lines changed: 7 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,7 @@
1+
;; Test WASM module with invalid export name starting with 'wasm:'
2+
(module
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(func $test (result i32)
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i32.const 42
5+
)
6+
(export "wasm:invalid" (func $test))
7+
)
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‎test/fixtures/es-modules/invalid-import-module.wasm‎

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‎test/fixtures/es-modules/invalid-import-module.wat‎

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+8Lines changed: 8 additions & 0 deletions
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@@ -0,0 +1,8 @@
1+
;; Test WASM module with invalid import module name starting with 'wasm-js:'
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(module
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(import "wasm-js:invalid" "test" (func $invalidImport (result i32)))
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(export "test" (func $test))
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(func $test (result i32)
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call $invalidImport
7+
)
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)
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‎test/fixtures/es-modules/invalid-import-name-wasm-js.wasm‎

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