Structural equality fail

[CraigStuntz]

This trivial test won't pass:

    [<Test>]
    member this.``structural equality``() =
        let actualList: char list = []
        [(actualList, "")] |> should equal [([], "")]

It fails with the interesting error:

Expected: [([], "")],
but was [([], "")]

However, it works correctly in FSI:

> let actualList: char list = [];;
   val actualList : char list = []
> [(actualList, "")] = [([], "")];;
   val it : bool = true

[sergey-tihon]

What unit testing framework do you use? NUnit?

[CraigStuntz]

Yes, that's NUnit. FsUnit appears to delegate equality to NUnit, which runs it through this horror show. It would probably be better if FsUnit did something closer to @forki's version.

[sergey-tihon]

Look like similar to this #21

[CraigStuntz]

It is certainly close to this comment on that issue, but implementing #21 won't fix the difference in behavior of should equal. I'm thinking that x |> should equal y and x = y should be isomorphic.

[sergey-tihon]

We should track discussion on NUnit repo
FsUnit.Typed should not has this issue.

[rprouse]

The NUnit team would appreciate comments and ideas on nunit/nunit#1249. Change will happen if we can come up with a way forward without breaking existing unit tests. As @sergey-tihon says, I don't think this is an FsUnit issue, but that of the underlying framework, NUnit 😄

[sergey-tihon]

Released in v2.2.0-beta1