onEnterFrame-generator-01.js

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// Frame properties and methods work in generator-resuming onEnterFrame events.

// Also tests onPop events, for good measure.

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

g.eval(`\

    function* gen(lo, hi) {

        var a = 1/2;

        yield a;

        yield a * a;

`);

let dbg = new Debugger;

let gw = dbg.addDebuggee(g);

let hits = 0;

let savedScript = null;

let savedEnv = null;

let savedOffsets = new Set;

function check(frame) {

    assertEq(frame.type, "call");

    assertEq(frame.constructing, false);

    assertEq(frame.callee, gw.makeDebuggeeValue(g.gen));

    // `arguments` elements don't work in resumed generator frames,

    // because generators don't keep the arguments around.

    // However, some of this is initialized when the frame.arguments object is

    // created, so if they are created during the first onEnterFrame or onPop

    // event, the properties exist, and those events can also see the values.

    assertEq(frame.arguments.length, args.length);

    for (var i = 0; i < args.length; i++) {

        assertEq(frame.arguments.hasOwnProperty(i), true);

        if (hits < 2)

            assertEq(frame.arguments[i], gw.makeDebuggeeValue(args[i]), `arguments[${i}]`);

        else

            assertEq(frame.arguments[i], undefined);

    if (savedEnv === null) {

        savedEnv = frame.environment;

        assertEq(savedScript, null);

        savedScript = frame.script;

    } else {

        assertEq(frame.environment, savedEnv);

        assertEq(frame.script, savedScript);

    let a_expected = hits < 3 ? undefined : 1/2;

    assertEq(savedEnv.getVariable("a"), a_expected);

    assertEq(frame.onStack, true);

    let pc = frame.offset;

    assertEq(savedOffsets.has(pc), false);

    savedOffsets.add(pc);

    assertEq(frame.older, null);

    assertEq(frame.this, gw.makeDebuggeeValue(g));

    assertEq(typeof frame.implementation, "string");

    // And the moment of truth:

    assertEq(frame.eval("2 + 2").return, 4);

    assertEq(frame.eval("a").return, a_expected);

    assertEq(frame.eval("if (a !== undefined) { assertEq(a < (lo + hi) / 2, true); } 7;").return, 7);

dbg.onEnterFrame = frame => {

    if (frame.type === "eval")

        return;

    check(frame);

    hits++;

    frame.onPop = completion => {

        check(frame);

        hits++;

};

};

// g.gen ignores the arguments passed to it, but we use them to test

// frame.arguments.

let args = [0, 10, g, dbg];

for (let v of g.gen(...args)) {}

assertEq(hits, 8);