superPropHomeObject.js

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// This is super weird. A super property reference in the spec contains two

// things. The first is the object to do the lookup on, the super base. This

// should be unchanged, no matter what's going on: I can move the method to

// another object. I can pull it out as its own function. I can put it on my

// head and run around the front yard. No changes. The other half, the |this|

// for invoked calls, is the this at the time of referencing the property, which

// means it's gonna vary wildly as stuff gets moved around.

class base {

    constructor() { }

    test(expectedThis) { assertEq(this, expectedThis); }

class derived extends base {

    constructor() { super(); }

    test(expected) { super.test(expected); }

    testArrow() { return (() => super.test(this)); }

    ["testCPN"](expected) { super.test(expected); }

let derivedInstance = new derived();

derivedInstance.test(derivedInstance);

derivedInstance.testCPN(derivedInstance);

let obj = { test: derivedInstance.test };

obj.test(obj);

// Classes are strict, so primitives are not boxed/turned into globals

let testSolo = derivedInstance.test;

testSolo(undefined);

let anotherObject = { };

derivedInstance.test.call(anotherObject, anotherObject);

let strThis = "this is not an object!";

derivedInstance.test.call(strThis, strThis);

// You can take the arrow function out of the super, ... or something like that

let arrowTest = derivedInstance.testArrow();

arrowTest();

// There's no magic "super script index" per code location.

class base1 {

    constructor() { }

    test() { return "llama"; }

class base2 {

    constructor() { }

    test() { return "alpaca"; }

let animals = [];

for (let exprBase of [base1, base2])

    new class extends exprBase {

        constructor() { super(); }

        test() { animals.push(super["test"]()); }

    }().test();

assertDeepEq(animals, ["llama", "alpaca"]);

if (typeof reportCompare === 'function')

    reportCompare(0,0,"OK");