Description
I'm currently trying to use rquickjs to run the JS parts of https://github.com/pyodide/pyodide to be able to statically embed a python interpreter into a rust executable.
This is of course a very large codebase, but I'm trying an iterative approach, where I just patch in enough support so that I get the correct calls to the WebAssembly objects.
However, I often get stuck when some JS Exception occurs.
Is there a way to, when ctx.eval returns an error, to get a stack trace or the line of code that caused the problem?
This is especially a problem with Promises, since a failed Promise often only returns "WouldBlock", although the underlying problem is an exception that happened somewhere along the way (usually a missing import or a function not being defined yet).
My attempt at logging an error is as follows:
fn run_js(ctx: &Context, script: &str) {
ctx.with(|ctx| {
let res: Result<Value, rquickjs::Error> = ctx.eval(script);
match res {
Err(e) => {
if e.is_exception() {
let exc = ctx.catch();
eprintln!("Exception during script evaluation: {exc:?}");
} else {
eprintln!("Error evaluating script: {:?}", e)
}
}
Ok(value) => {
if value.is_promise() {
let p = value.into_promise().unwrap();
let v: Result<Value, rquickjs::Error> = p.finish();
if let Err(e) = v{
if e.is_exception() {
let exc = ctx.catch();
eprintln!("Exception during promise execution: {exc:?}");
} else {
eprintln!("Error during promise execution: {e:?} {p:?}");
let p = p.into_inner();
eprintln!("Promise inner: {:?}", p);
let p = p.into_inner();
eprintln!("Promise object inner: {:?}", p);
let prom = p.as_promise().unwrap();
let res: Result<Value, rquickjs::Error> = prom.finish();
eprintln!("Inner promise error: {res:?}");
}
} else {
eprintln!("Script evaluated with promise resulting in {:?}", v);
}
} else {
eprintln!("Script evaluated with value {:?}", value);
}
}
}
});
}This then prints something like
Error during promise execution: WouldBlock Promise(Object(Promise(0x62b51d48ce10)))
Promise inner: Object(Promise(0x62b51d48ce10))
Promise object inner: Promise(0x62b51d48ce10)
Inner promise error: Err(WouldBlock)
Thank you in advance!