Error in tests for utils on Julia 0.5

[dfdx]

Currently Pkg.test("Boltzmann") fails with pretty interesting error:

ERROR: LoadError: LoadError: TypeError: _collect: in typeassert, expected Boltzmann.RBM{Float64,Distributions.Normal,Distributions.Bernoulli}, got Boltzmann.RBM{Float64,Distributions.Normal,Distributions.Bernoulli}

This message to the line 286:

rbms = map(i -> deepcopy(rbm), 1:length(args))

which is supposed to simply create 2 clones of RBM. Strangely enough, error disappears if I add call:

deepcopy(rbm)

just before the line described.

This sound pretty much like a bug in Julia itself (I'm on 0.5.0 currently), but I wasn't able to create a minimal reproducible example to submit an issue. @Rory-Finnegan maybe you know some details of what may be going here or ideas how to make a minimal example?

[rofinn]

@dfdx I have no idea why that would be happening in 0.5, but I agree that this seems like a bug in julia and warrants opening an issue. As for your fix, it seems appropriate given that it only impacts the test code. Personally, I might include a comment about the issue, but that's just me.

[dfdx]

After some time I was able to narrow the issue to a standalone example - see JuliaLang/julia#19041. In our case problematic component is Bernoulli type from Distributions. It turns out, Bernoulli takes type parameter T<:Real, and if it isn't passed, inference sometimes fails with that weird message.

I'm going to give it a couple of days and then use whatever workearound to make tests stable.