Comparing sequences fails

Description

The following fails:

Seq.init 100 ((+) 1)
|> should equal (Seq.init 100 ((+) 1))

Repro steps

See above.

Expected behavior

Should succeed.

Actual behavior

Gives test error:

FsUnit.Xunit+MatchException : Exception of type 'FsUnit.Xunit+MatchException' was thrown.
Expected: Equals seq [1; 2; 3; 4; ...]
Actual:   seq [1; 2; 3; 4; ...]

Which is rather confusing as it doesn’t show where the two sequences diverge (spoiler alert: they don’t 😉 ).

Known workarounds

A workaround is to not use sequences in tests

I.e.: turning them into eager collections works fine:

Seq.init 100 ((+) 1)
|> Array.ofSeq
|> should equal (Seq.init 100 ((+) 1) |> Array.ofSeq)

Related information

Version 5.0.5 Using: FsUnit.Xunit

[abelbraaksma]

I was counting on that, otherwise why add it, right?

[CaptnCodr]

You are not the only one who needs/needed this. 😉