TypeError: in new, expected DataType, got Type{ZeroBundle{1, B}}

[fredrikekre]

Simple example of taking the jacobian of the identity function, but the identity function is a comprehension

julia> import AbstractDifferentiation as AD

julia> function identity_comprehension(x)
           return [x[i] for i in eachindex(x)]
       end
identity_comprehension (generic function with 1 method)

julia> AD.jacobian(Diffractor.DiffractorForwardBackend(), identity_comprehension, rand(2))
ERROR: TypeError: in new, expected DataType, got Type{ZeroBundle{1, B}}
Stacktrace:
  [1] _TangentBundle
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/tangent.jl:148 [inlined]
  [2] TangentBundle
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/tangent.jl:251 [inlined]
  [3] (::Diffractor.∂☆internal{1})(args::Vararg{Diffractor.AbstractTangentBundle{1}})
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/stage1/forward.jl:149 [inlined]
  [4] (::Diffractor.∂☆{N})(args::Vararg{Diffractor.AbstractTangentBundle{N}}) where N
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/stage1/forward.jl:160 [inlined]
  [5] collect
    @ Diffractor ./array.jl:841 [inlined]
  [6] (::Diffractor.∂☆recurse{…})(::ZeroBundle{…}, ::Diffractor.CompositeBundle{…})
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/stage1/recurse_fwd.jl:0
  [7] (::Diffractor.∂☆internal{1})(::ZeroBundle{1, typeof(collect)}, ::Vararg{Diffractor.AbstractTangentBundle{1}})
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/stage1/forward.jl:121
  [8] (::Diffractor.∂☆{1})(::ZeroBundle{1, typeof(collect)}, ::Vararg{Diffractor.AbstractTangentBundle{1}})
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/stage1/forward.jl:160
  [9] identity_comprehension
    @ Diffractor ./REPL[7]:2 [inlined]
 [10] ∂☆internal
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/stage1/forward.jl:121 [inlined]
 [11] (::Diffractor.∂☆{N})(args::Vararg{Diffractor.AbstractTangentBundle{N}}) where N
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/stage1/forward.jl:160 [inlined]
 [12] (::Diffractor.var"#pushforward#359"{typeof(identity_comprehension), Tuple{Vector{Float64}}})(vs::Tuple{Vector{Float64}})
    @ Diffractor ~/.julia/packages/Diffractor/QyO8B/src/AbstractDifferentiation.jl:13
 [13] (::Diffractor.var"#358#362")(cols::Any)
    @ Diffractor ~/.julia/packages/AbstractDifferentiation/eEkWP/src/AbstractDifferentiation.jl:526 [inlined]
 [14] mapslices(f::Diffractor.var"#358#362"{Diffractor.var"#pushforward#359"{…}}, A::Matrix{Float64}; dims::Int64)
    @ Base ./abstractarray.jl:3179
 [15] jacobian(b::Diffractor.DiffractorForwardBackend, f::Function, args::Vector{Float64})
    @ Diffractor ~/.julia/packages/AbstractDifferentiation/eEkWP/src/AbstractDifferentiation.jl:524