mock the same function twice in the same test differently based on the argument I sent

Question

I have the following code:

it('Should return error', async () => {
  const searchMetadata = {
    details: {}
  };
  sandbox.mock(resultService).expects('doesSearchExists').atLeast(1).resolves(true);
  sandbox.mock(resultService).expects('doesSearchExists').atLeast(1).withArgs("limit").resolves(false);
  sandbox.mock(analyticsService).expects('getMetadata').throws(UNABLE_TO_CALCULATE_METADATA);
  await GET(request, res, (result: any) => {
    expect(result).to.be.deep.equal(UNABLE_TO_CALCULATE_METADATA)
  });
});

As you can see I am trying to mock the same function doesSearchExists twice differently based on the argument I sent. If limit is sent doesSearchExists should return false and if limit is missing doesSearchExists should return true. But when I try it I get

TypeError: Attempted to wrap doesSearchExists which is already wrapped

any idea how I can achieve the above?

Answer 1

I made a runnable example that fixes your issue.

// Employs 'mini-mocha' to emulate running in the Mocha test runner (mochajs.org)
require("@fatso83/mini-mocha").install();

const sinon = require("sinon");
const {assert} = require('@sinonjs/referee');

// The SUT
const resultService = {
    doesSearchExists(arg) {}
}

describe("SO67960235", function() {
    const sandbox = sinon.createSandbox();

    it('Should return error <-- this title is wrong', async () => {

      // setup mocks
      const mock = sandbox.mock(resultService)
      mock.expects('doesSearchExists').atLeast(1).resolves(true);
      mock.expects('doesSearchExists').atLeast(1).withArgs("limit").resolves(false);
      
      // call your external methods that exercise your mocks
      console.log(await resultService.doesSearchExists("foo")); // true
      console.log(await resultService.doesSearchExists("limit")); // false

      // verify that they were called as expected
      mock.verify();
    });
});