Frame-asyncPromise-04.js

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// Test the promise property on async generator function frames.

load(libdir + 'asserts.js');

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

var dbg = Debugger(g);

g.eval(`

async function* f() {

  debugger;

  yield 42;

  debugger;

  return 50

`);

let frame;

const promises = [];

dbg.onEnterFrame = function(f) {

  frame = f;

  promises.push(["enter", frame.asyncPromise]);

  frame.onPop = function() {

    promises.push(["leave", frame.asyncPromise]);

};

  dbg.onDebuggerStatement = function(f) {

    assertEq(f, frame);

    promises.push(["dbg", frame.asyncPromise]);

};

};

(async () => {

  const it = g.f();

  // Promise is null until initial iteration.

  assertEq(frame.asyncPromise, null);

  assertEq(promises.length, 2);

  assertEq(promises[0][0], "enter");

  assertEq(promises[0][1], null);

  assertEq(promises[1][0], "leave");

  assertEq(promises[1][1], null);

  const result1Promise = it.next();

  const frameIt1Promise = frame.asyncPromise;

  assertEq(frameIt1Promise instanceof Debugger.Object, true);

  assertEq(frameIt1Promise.unsafeDereference(), result1Promise);

  assertEq(promises.length, 5);

  assertEq(promises[2][0], "enter");

  assertEq(promises[2][1], frameIt1Promise);

  assertEq(promises[3][0], "dbg");

  assertEq(promises[3][1], frameIt1Promise);

  assertEq(promises[4][0], "leave");

  assertEq(promises[4][1], frameIt1Promise);

  await result1Promise;

  // Iteration step has fully completed, so promise state has been cleared.

  assertEq(frame.asyncPromise, null);

  assertEq(promises.length, 7);

  assertEq(promises[5][0], "enter");

  assertEq(promises[5][1], frameIt1Promise);

  assertEq(promises[6][0], "leave");

  assertEq(promises[6][1], frameIt1Promise);

  const result2Promise = it.next();

  const frameIt2Promise = frame.asyncPromise;

  assertEq(frameIt2Promise instanceof Debugger.Object, true);

  assertEq(frameIt2Promise.unsafeDereference(), result2Promise);

  assertEq(frameIt1Promise !== frameIt2Promise, true);

  assertEq(promises.length, 10);

  assertEq(promises[7][0], "enter");

  assertEq(promises[7][1], frameIt2Promise);

  assertEq(promises[8][0], "dbg");

  assertEq(promises[8][1], frameIt2Promise);

  assertEq(promises[9][0], "leave");

  assertEq(promises[9][1], frameIt2Promise);

  await result2Promise;

  // Frame has terminated, so accessing the property throws.

  assertThrowsInstanceOf(() => frame.asyncPromise, Error);

  assertEq(promises.length, 12);

  assertEq(promises[10][0], "enter");

  assertEq(promises[10][1], frameIt2Promise);

  assertEq(promises[11][0], "leave");

  assertEq(promises[11][1], frameIt2Promise);

})();