Description
Describe the bug
Node's async_hooks apparently adds symbol-named own properties to Promise.prototype and to (some?) individual promises. For passStyleOf to judge a promise passable, ideally it should not have any own properties. However, to accommodate the own properties added by Node's async_hooks to an individual promise, checkPromiseOwnKeys allows symbol-named own properties if they also already appear on Promise.prototype and the properties are visibly safe enough(*).
However, under the vscode debugger, entered using vscode JavaScript Debug Terminal, I have several times run into the
Must not have any own properties: ["[Symbol(async_id_symbol)]","[Symbol(trigger_async_id_symbol)]"]
error, apparently because async_hooks added these to an individual promise instance but not to Promise.prototype.
(*) This should test that the property is a non-configurable non-writable own data property with a visibly harmless value, such as a primitive. However, currently the test seems weaker than that and should be tightened.
Steps to reproduce
Check out a current endo and yarn && yarn build
In vscode, set a breakpoint at
endo/packages/ses/src/error/assert.js
Line 373 in 895ea0a
// The next line is a particularly fruitful place to put a breakpoint.
return error;In a vscode JavaScript Debug Terminal, run
$ cd packages/cli
$ yarn test test/demo/index.test.jsIf the debugger then runs until it stops in the state captured below, you've reproduced the problem.
(Note: Currently speculative that this happens on endo master. Currently I'm on a draft branch with changes that should make no difference. But not sure.)
Expected behavior
Not hitting this error
Platform environment
- What OS are you using?
- MacOS 15.1.1 (24B91)
- What version of Node.js?
- v18.19.0
- Is there anything special/unusual about your platform?
- not that I can think of, that could possibly be relevant.
- What version of Endo are you using? (run
git describe --tags --always)- @endo/[email protected]
Additional context
I am currently working on a local draft of the markm-flip-non-trapping-shim-default branch. I will check later if this also happens on master.
Screenshots
cli(markm-flip-non-trapping-shim-default)$ yarn test test/demo/index.test.jsError: "[Promise]" - Must not have any own properties: ["[Symbol(async_id_symbol)]","[Symbol(trigger_async_id_symbol)]"]
at makeError (file:///Users/markmiller/src/ongithub/endojs/endo/packages/ses/src/error/assert.js:359:61)
at fail (file:///Users/markmiller/src/ongithub/endojs/endo/packages/ses/src/error/assert.js:491:20)
at baseAssert (file:///Users/markmiller/src/ongithub/endojs/endo/packages/ses/src/error/assert.js:513:13)
at assertChecker (file:///Users/markmiller/src/ongithub/endojs/endo/packages/pass-style/src/passStyle-helpers.js:78:3)
at reject (file:///Users/markmiller/src/ongithub/endojs/endo/packages/pass-style/src/passStyle-helpers.js:93:34)
at checkPromiseOwnKeys (file:///Users/markmiller/src/ongithub/endojs/endo/packages/pass-style/src/safe-promise.js:42:6)
const checkPromiseOwnKeys = (pr, check) => {
const keys = ownKeys(pr);
if (keys.length === 0) {
return true;
}
/**
* This excludes those symbol-named own properties that are also found on
* `Promise.prototype`, so that overrides of these properties can be
* explicitly tolerated if they pass the `checkSafeOwnKey` check below.
* In particular, we wish to tolerate
* * An overriding `toStringTag` non-enumerable data property
* with a string value.
* * Those own properties that might be added by Node's async_hooks.
*/
const unknownKeys = keys.filter(
key => typeof key !== 'symbol' || !hasOwnPropertyOf(Promise.prototype, key),
);
if (unknownKeys.length !== 0) {
return CX(
check,
)`${pr} - Must not have any own properties: ${q(unknownKeys)}`;
}
// ...
};In the vscode Debug Console when looking at the checkPromiseOwnKeys stack frame
Object.getOwnPropertyDescriptors(Promise.prototype)
{constructor: {…}, then: {…}, catch: {…}, finally: {…}, Symbol(Symbol.toStringTag): {…}}
catch = {value: ƒ, writable: false, enumerable: false, configurable: false}
constructor = {get: ƒ, set: ƒ, enumerable: false, configurable: false}
finally = {value: ƒ, writable: false, enumerable: false, configurable: false}
Symbol(Symbol.toStringTag) = {value: 'Promise', writable: false, enumerable: false, configurable: false}
then = {value: ƒ, writable: false, enumerable: false, configurable: false}
toString = ƒ [prop]() {\n return value;\n }
valueOf = ƒ [prop]() {\n return value;\n }
Object.getOwnPropertyDescriptors(pr)
{Symbol(async_id_symbol): {…}, Symbol(trigger_async_id_symbol): {…}}
Symbol(async_id_symbol) = {value: 15589, writable: false, enumerable: true, configurable: false}
Symbol(trigger_async_id_symbol) = {value: 15579, writable: false, enumerable: true, configurable: false}
toString = ƒ [prop]() {\n return value;\n }
valueOf = ƒ [prop]() {\n return value;\n }