尝试和未能通过茉莉花测试诺言

Question

(all this example code is coffeescript)

I have a generic promise like so:

describe "foo", () ->
  it "foo", () ->

    p = new Promise (r) -> r(1)
    p.then (x) ->
      console.log("promise run")
      expect(x).toEqual(2)

This is expected to fail, but it doesn't. The expectation is never hit and nothing is logged either.

From the jasmine team's blog post on the topic it seems I can write something like this:

p.then (x) ->
  expect(x).toEqual(2)
  done()

but it has the same effect.

The blog post recommends the mock-promises library, which I used to write this:

p.then (x) ->
  console.log x
  expect(x).toEqual(2)
MockPromises.executeForPromise(p);

but it has the same effect (the expectation is never hit)

Answer 1

Instant gratification:

it's an easy fix:

all I needed to do was pass done as an argument to the it function:

describe "foo", () ->
  it "foo", (done) ->
    p = new Promise (r) -> r(1)
    p.then (x) ->
      console.log x
      expect(x).toEqual(2)
      done()

Thanks to a suggestion in the comments I should also add

.catch(done)

at the end so that failed cases don't just time out.