queue.spec.ts

import * as sinon from "sinon";
import * as chai from "chai";

chai.use(require("chai-as-promised"));
const { expect } = chai;

const Queue = require("../queue");

const TEST_ERROR = new Error("foobar");

describe("Queue", () => {
  it("should handle tasks", () => {
    const handler = sinon.stub().resolves();
    const q = new Queue({
      handler,
    });

    q.add(4);
    q.close();
    q.process();

    return q.wait()
      .then(() => {
        expect(handler.callCount).to.equal(1);
      });
  });

  it("should not retry", () => {
    const handler = sinon.stub().rejects(TEST_ERROR);
    const q = new Queue({
      handler,
      retries: 0,
    });

    q.add(4);
    q.close();
    q.process();

    return q.wait()
      .then(() => {
        throw new Error("handler should have rejected");
      })
      .catch((err: Error) => {
        expect(err).to.equal(TEST_ERROR);
      })
      .then(() => {
        expect(handler.callCount).to.equal(1);
      });
  });

  it("should retry the number of retries, plus one", () => {
    const handler = sinon.stub().rejects(TEST_ERROR);
    const q = new Queue({
      backoff: 0,
      handler,
      retries: 3,
    });

    q.add(4);
    q.close();
    q.process();

    return q.wait()
      .then(() => {
        throw new Error("handler should have rejected");
      })
      .catch((err: Error) => {
        expect(err).to.equal(TEST_ERROR);
      })
      .then(() => {
        expect(handler.callCount).to.equal(4);
      });
  });
});