debugger-early-reaction.js

Enable keyboard shortcuts

// |jit-test| skip-if: !wasmJSPromiseIntegrationEnabled()

// Regression test for bug 2045460:

// A debugger can extract the internal reaction registered on a JSPI suspending

// promise (via Debugger.Object.prototype.getPromiseReactions) and invoke it

// (via Debugger.Object.prototype.call) while that promise is still pending.

// This resumes the suspended continuation early, which used to read the result

// slot of a pending promise and trip an assertion in GetPromiseResults. The

// engine must now fail cleanly instead of asserting/crashing.

var g = newGlobal({newCompartment: true});

var dbg = new Debugger();

var gw = dbg.addDebuggee(g);

g.eval(`

  var resolveFn;

  var userPromise = new Promise(r => { resolveFn = r; });

  var suspending = new WebAssembly.Suspending(() => userPromise);

  var bin = wasmTextToBinary('(module (import "m" "s" (func $s (result externref))) (func (export "f") (result externref) call $s))');

  var inst = new WebAssembly.Instance(new WebAssembly.Module(bin), {m:{s:suspending}});

  var p = WebAssembly.promising(inst.exports.f);

  var settled = false;

  p().then(v => { settled = "resolved"; }, e => { settled = "rejected"; });

`);

var promiseDO = gw.makeDebuggeeValue(g.userPromise);

var reactions = promiseDO.getPromiseReactions();

for (var r of reactions) {

  if (r.resolve) {

    // Resumes the suspended continuation early while userPromise is pending.

    // Must not assert; the early resume is reported as a clean failure.

    r.resolve.call(undefined);

drainJobQueue();

print("ok");