Flux.jl/test/optimise.jl

using Flux.Optimise
using Flux.Tracker

@testset "Optimise" begin
  w = randn(10, 10)
  @testset for Opt in [SGD, Nesterov, Momentum, ADAM, AdaMax, RMSProp, ps -> ADAGrad(ps, 0.1), ADADelta, AMSGrad, NADAM]
    w′ = param(randn(10, 10))
    loss(x) = Flux.mse(w*x, w′*x)
    opt = Opt([w′])
    for t=1:10^5
      l = loss(rand(10))
      back!(l)
      opt()
    end
    @test Flux.mse(w, w′) < 0.01
  end
end

@testset "Training Loop" begin
  i = 0
  l = param(1)

  Flux.train!(() -> (sleep(0.1); i += 1; l),
              Iterators.repeated((), 100),
              ()->(),
              cb = Flux.throttle(() -> (i > 3 && :stop), 1))

  @test 3 < i < 50
end