Skip to content

Unexpectedly call getter/setter when subclassing #36976

@unadlib

Description

@unadlib

TypeScript Version: 3.7.x-dev.201xxxxx

Search Terms:
getter/setter, subclassing

Code

const x: any = []
class A {
    a() { 
        x.push(this);
        return this;
    }

    get s() { 
        x.push(this);
        return this;
    }

    set s(n: any) { 
        x.push(this);
    }
}

class B extends A {
    a() {
        x.push(this);
        return super.a();
    }

    get s() { 
        x.push(this);
        // @ts-ignore
        return super.s;
    }

    set s(n: any) {
        x.push(this);
        // @ts-ignore
        super.s = n;
    }
}

const b = new B(); b.a(); b.s; b.s = 1;
console.log([x[0] === x[1], x[2] === x[3], x[4] === x[5]]);

ts compiler:Only public and protected methods of the base class are accessible via the 'super' keyword.ts(2340) and // @ts-ignore.

Output
"use strict";
var __extends = (this && this.__extends) || (function () {
    var extendStatics = function (d, b) {
        extendStatics = Object.setPrototypeOf ||
            ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
            function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
        return extendStatics(d, b);
    };
    return function (d, b) {
        extendStatics(d, b);
        function __() { this.constructor = d; }
        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
    };
})();
var x = [];
var A = /** @class */ (function () {
    function A() {
    }
    A.prototype.a = function () {
        x.push(this);
        return this;
    };
    Object.defineProperty(A.prototype, "s", {
        get: function () {
            x.push(this);
            return this;
        },
        set: function (n) {
            x.push(this);
        },
        enumerable: true,
        configurable: true
    });
    return A;
}());
var B = /** @class */ (function (_super) {
    __extends(B, _super);
    function B() {
        return _super !== null && _super.apply(this, arguments) || this;
    }
    B.prototype.a = function () {
        x.push(this);
        return _super.prototype.a.call(this);
    };
    Object.defineProperty(B.prototype, "s", {
        get: function () {
            x.push(this);
            // @ts-ignore
            return _super.prototype.s;
        },
        set: function (n) {
            x.push(this);
            // @ts-ignore
            _super.prototype.s = n;
        },
        enumerable: true,
        configurable: true
    });
    return B;
}(A));
var b = new B();
b.a();
b.s;
b.s = 1;
console.log([x[0] === x[1], x[2] === x[3], x[4] === x[5]]);
Compiler Options
{
  "compilerOptions": {
    "target": "es5"
  }
}

Expected behavior:
[ true, true, true ]

Actual behavior:
[ true, false, false ]

Playground Link:

Related Issues:
Allow to call getter/setter logic When subclassing

Metadata

Metadata

Assignees

No one assigned

    Labels

    DuplicateAn existing issue was already created

    Type

    No type
    No fields configured for issues without a type.

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions