Object-forceLexicalInitializationByName.js

Enable keyboard shortcuts

load(libdir + "asserts.js");

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

var dbg = new Debugger;

var gw = dbg.addDebuggee(g);

let errorOne, errorTwo;

function evalErrorStr(global, evalString) {

    try {

        global.evaluate(evalString);

        return undefined;

    } catch (e) {

        return e.toString();

assertEq(evalErrorStr(g, "let y = IDONTEXIST;"), "ReferenceError: IDONTEXIST is not defined");

assertEq(evalErrorStr(g, "y = 1;"),

         "ReferenceError: can't access lexical declaration 'y' before initialization");

// Here we flip the uninitialized binding to undfined.

assertEq(gw.forceLexicalInitializationByName("y"), true);

assertEq(g.evaluate("y"), undefined);

g.evaluate("y = 1;");

assertEq(g.evaluate("y"), 1);

// Ensure that bogus bindings return false, but otherwise trigger no error or

// side effect.

assertEq(gw.forceLexicalInitializationByName("idontexist"), false);

assertEq(evalErrorStr(g, "idontexist"), "ReferenceError: idontexist is not defined");

// Ensure that ropes (non-atoms) behave properly

assertEq(gw.forceLexicalInitializationByName(("foo" + "bar" + "bop" + "zopple" + 2 + 3).slice(1)),

                                             false);

assertEq(evalErrorStr(g, "let oobarbopzopple23 = IDONTEXIST;"), "ReferenceError: IDONTEXIST is not defined");

assertEq(gw.forceLexicalInitializationByName(("foo" + "bar" + "bop" + "zopple" + 2 + 3).slice(1)),

                                             true);

assertEq(g.evaluate("oobarbopzopple23"), undefined);

// Ensure that only strings are accepted by forceLexicalInitializationByName

const bad_types = [

    2112,

    {geddy: "lee"},

    () => 1,

[],

    Array,

    "'1'", // non-identifier

for (var badType of bad_types) {

    assertThrowsInstanceOf(() => {

        gw.forceLexicalInitializationByName(badType);

    }, TypeError);

// Finally, supplying no arguments should throw a type error

assertThrowsInstanceOf(() => {

    Debugger.isCompilableUnit();

}, TypeError);