re-enable tests (#41)

* re-enable tests

* add StatsFuns as a test dependency

* Test show

* install Zygote and IRTools in tests.

* fixing zygote tests

.travis.yml

@@ -21,8 +21,8 @@ matrix:
 #  apt: # apt-get for linux
 #    packages:
 #    - gfortran
-before_script:
-  - julia -e 'using Pkg; pkg"add Zygote#master IRTools#master"'
+# before_script:
+#   - julia -e 'using Pkg; pkg"add Zygote#master IRTools#master"'
 jobs:
   include:
     - stage: "Documentation"

Project.toml

@@ -22,8 +22,10 @@ Flux = "587475ba-b771-5e3f-ad9e-33799f191a9c"
 ForwardDiff = "f6369f11-7733-5829-9624-2563aa707210"
 ReverseDiff = "37e2e3b7-166d-5795-8a7a-e32c996b4267"
 StatsBase = "2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91"
+StatsFuns = "4c63d2b9-4356-54db-8cca-17b64c39e42c"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 
 [targets]
-test = ["Distributions", "Documenter", "Flux", "ForwardDiff", "ReverseDiff", "Test", "StatsBase", "Zygote"]
+test = ["Distributions", "Documenter", "Flux", "ForwardDiff", "ReverseDiff", "Test", "StatsBase",
+        "StatsFuns", "Zygote"]

src/AD_Zygote.jl

@@ -19,7 +19,7 @@ Base.show(io::IO, ∇ℓ::ZygoteGradientLogDensity) = print(io, "Zygote AD wrapp
 function logdensity(::Type{ValueGradient}, ∇ℓ::ZygoteGradientLogDensity, x::AbstractVector)
     @unpack ℓ = ∇ℓ
     y, back = Zygote.forward(_logdensity_closure(ℓ), x)
-    gradient = isfinite(y) ? back(Int8(1)) : zeros(typeof(y), length(y))
+    gradient = isfinite(y) ? back(Int8(1))[1] : zeros(typeof(y), length(y))
     ValueGradient(y, gradient)
 end
 

test/runtests.jl

@@ -311,11 +311,15 @@ end
 
 if VERSION ≥ v"1.1.0"
     # cf https://github.com/FluxML/Zygote.jl/issues/104
-
+    import Pkg # use latest versions until tagged
+    Pkg.add(Pkg.PackageSpec(name = "IRTools", rev = "master"))
+    Pkg.add(Pkg.PackageSpec(name = "Zygote", rev = "master"))
     import Zygote
 
     @testset "AD via Zygote" begin
-        ∇ℓ = ADgradient(:Zygote, TestLogDensity())
+        ℓ = TestLogDensity()
+        ∇ℓ = ADgradient(:Zygote, ℓ)
+        @test repr(∇ℓ) == ("Zygote AD wrapper for " * repr(ℓ))
         @test dimension(∇ℓ) == 3
         buffer = randn(3)
         vb = ValueGradientBuffer(buffer)
@@ -324,9 +328,9 @@ if VERSION ≥ v"1.1.0"
             @test logdensity(Real, ∇ℓ, x) ≈ test_logdensity(x)
             @test logdensity(Value, ∇ℓ, x) ≅ Value(test_logdensity(x))
             vg = ValueGradient(test_logdensity(x), test_gradient(x))
-            @test_skip logdensity(ValueGradient, ∇ℓ, x) ≅ vg
+            @test logdensity(ValueGradient, ∇ℓ, x) ≅ vg
             # NOTE don't test buffer ≡, as that is not implemented for Zygote
-            @test_skip logdensity(vb, ∇ℓ, x) ≅ vg
+            @test logdensity(vb, ∇ℓ, x) ≅ vg
         end
     end
 end