swc/crates/swc_ecma_parser/tests/tsc/privateNamesAndFields.ts

// @strict: true
// @target: es6

class A {
    #foo: number;
    constructor () {
        this.#foo = 3;
    }
}

class B extends A {
    #foo: string;
    constructor () {
        super();
        this.#foo = "some string";
    }
}