Discussion on: Tribonacci

"use strict";

class LogInvalidIntegerError extends Error {
    constructor(...parameters) {
        super(...parameters);

        this.name = "LogInvalidIntegerError";
    }
}

function logInteger(x) {
    if (!Number.isInteger(x)) {
        throw new LogInvalidIntegerError("First argument must be an integer");
    }

    console.log(`Integer: ${x}`);
}

try {
    logInteger(1);
    // Integer: 1

    logInteger(1.2);
    // LogInvalidIntegerError: First argument must be an integer
} catch (error) {
    if (error instanceof LogInvalidIntegerError) {
        console.error("Nope, integers only.");
    } else {
        console.error(`Unhandled error: ${error.toString()}`);
    }
}

"use strict";

import "mocha";
import { expect } from "chai";
import { logInteger, LogInvalidIntegerError } from "../src/log.js";

describe("log.js", function() {
    describe("logInteger", function() {
        it("should throw an exception on non-integer", function() {
            expect(log(1.2)).to.throw(LogInvalidIntegerError);
        });
    });
});