Make getproperty on Composite unthunk (#121)

* Make `getproperty` on `Composite` unthunk

* Bump patch version

Author: nickrobinson251

Project.toml

@@ -1,6 +1,6 @@
 name = "ChainRulesCore"
 uuid = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"
-version = "0.9.15"
+version = "0.9.16"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
@@ -11,7 +11,7 @@ BenchmarkTools = "0.5"
 FiniteDifferences = "0.10"
 MuladdMacro = "0.2.1"
 StaticArrays = "0.11, 0.12"
-julia = "^1.0"
+julia = "1"
 
 [extras]
 BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"

src/differentials/composite.jl

@@ -68,14 +68,15 @@ Base.convert(::Type{<:Tuple}, comp::Composite{<:Any, <:Tuple}) = backing(comp)
 Base.convert(::Type{<:Dict}, comp::Composite{<:Dict, <:Dict}) = backing(comp)
 
 Base.getindex(comp::Composite, idx) = getindex(backing(comp), idx)
-Base.getproperty(comp::Composite, idx::Int) = getproperty(backing(comp), idx)  # for Tuple
 
+# for Tuple
+Base.getproperty(comp::Composite, idx::Int) = unthunk(getproperty(backing(comp), idx))
 function Base.getproperty(
     comp::Composite{P, <:NamedTuple{L}}, idx::Symbol
 ) where {P, L}
     # Need to check L directly, or else this does not constant-fold
     idx ∈ L || return Zero()
-    return getproperty(backing(comp), idx)
+    return unthunk(getproperty(backing(comp), idx))
 end
 
 Base.keys(comp::Composite) = keys(backing(comp))

test/differentials/composite.jl

@@ -53,6 +53,8 @@ end
         @test keys(Composite{Tuple{Float64,}}(2.0)) == Base.OneTo(1)
         @test propertynames(Composite{Tuple{Float64,}}(2.0)) == (1,)
         @test getproperty(Composite{Tuple{Float64,}}(2.0), 1) == 2.0
+        @test getproperty(Composite{Tuple{Float64,}}(@thunk 2.0^2), 1) == 4.0
+        @test getproperty(Composite{Tuple{Float64,}}(a=(@thunk 2.0^2),), :a) == 4.0
 
         @test length(Composite{Foo}(x=2.5)) == 1
         @test length(Composite{Tuple{Float64,}}(2.0)) == 1