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// Like Frame-onStep-generator-resumption-01.js, but bail out by throwing.
let g = newGlobal({newCompartment: true});
g.eval(`
function* f() {
yield 1;
}
`);
// Try force-returning from one of the instructions in `f` before the initial
// yield. In detail:
//
// * This test calls `g.f()` under the Debugger.
// * It uses the Debugger to step `ttl` times.
// If we reach the initial yield before stepping the `ttl`th time, we're done.
// * Otherwise, the test tries to force-return from `f`.
// * That's an error, so the uncaughtExceptionHook is called.
// * The uncaughtExceptionHook returns a `throw` completion value.
//
// Returns `true` if we reached the initial yield, false otherwise.
//
// Note that this function is called in a loop so that every possible relevant
// value of `ttl` is tried once.
function test(ttl) {
let dbg = new Debugger(g);
let exiting = false; // we ran out of time-to-live and have forced return
let done = false; // we reached the initial yield without forced return
let reported = false; // a TypeError was reported.
dbg.onEnterFrame = frame => {
assertEq(frame.callee.name, "f");
dbg.onEnterFrame = undefined;
frame.onStep = () => {
if (ttl == 0) {
exiting = true;
// This test case never resumes the generator after the initial
// yield. Therefore the initial yield has not happened yet. So this
// force-return will be an error.
return {return: "ponies"};
}
ttl--;
};
frame.onPop = completion => {
if (!exiting)
done = true;
};
};
dbg.uncaughtExceptionHook = (exc) => {
// When onStep returns an invalid resumption value,
// the error is reported here.
assertEq(exc instanceof TypeError, true);
reported = true;
return {throw: "FAIL"}; // Bail out of the test.
};
let result;
let caught = undefined;
try {
result = g.f();
} catch (exc) {
caught = exc;
}
if (done) {
assertEq(reported, false);
assertEq(result instanceof g.f, true);
assertEq(caught, undefined);
} else {
assertEq(reported, true);
assertEq(caught, "FAIL");
}
dbg.enabled = false;
return done;
}
for (let ttl = 0; !test(ttl); ttl++) {}