Unit testing against properties in an Apply with C#.... How do you do that? Assert's throw and exception, which is how the frameworks pick it up, but Exceptions in an Apply are swallowed. How do you get access to the value "outside" of the apply? or should I look at some kind of extension to extract the value outside the method and assert there?

You can await outputs https://github.com/pulumi/examples/blob/master/testing-unit-cs/WebserverStackTests.cs#L47

glad you sent that, that was what I was about to build... would be better if it was supplied, but I can see that it would be abused in a real scenario...

In .NET does that code work, @worried-knife-31967? In TS, it wouldn't: the code in the

Apply()

would happen asynchronously, and almost certainly after the

ShouldBe()

.

Well it is a race condition but he is mocking all of the other resources so I don't think he actually had any asynchronous dependents so he might've just got lucky that his code was executing synchronously causing that use of

.Apply

to work for him

There are libraries for async testing in Node. Hopefully there's similar support in .NET. The general pattern is to declare the test function async, and await the async code. Does that work in .NET?

yea that is what Mikhail suggested

Something like

[TestMethod]
public async Task CorrectlyFailingTest()
{
  var frontdoor = resources.OfType<Frontdoor>().FirstOrDefault();
  (await frontdoor.BackendPools.Apply(bp => {
    return bp.Count();
  })).GetValueAsync().ShouldBe(1);
}

actually you don't use apply anymore you just await the output directly so:

var backendPools = await frontdoor.BackendPools.GetValueAsync();
var backendPoolCount = backendPools.Count();

Nice. I want one of those for Node 🙂

Here you go

const promise = <T>(output: pulumi.Output<T>): Promise<T | undefined> =>
  (output as any).promise() as Promise<T>;

it("should have a tag:key Name", async () => {
  const tags = await promise(vpc.tags);
  expect(tags).to.include.keys("Name");
  expect(tags?.Name).to.equal("my_app");
});

I use Chai As Promised.

const promise = <T>(output: pulumi.Output<T>): Promise<T | undefined> =>
  (output as any).promise() as Promise<T>;

it("should have a tag:key Name", async () => {
  expect(vpc.tags).to.eventually.include.keys("Name");
  expect(vpc.tags?.Name).to.eventually.equal("my_app");
});