getindex method ambiguities with AbstractTrees, Base, and OffsetArrays

[chriselrod]

julia> using ArrayInterface, OffsetArrays, Test

julia> amb = Test.detect_ambiguities(ArrayInterface, OffsetArrays)
5-element Vector{Tuple{Method, Method}}:
 (getindex(x::ArrayInterface.LazyAxis, i::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/axes.jl:293, getindex(r::AbstractUnitRange, s::Base.IdentityUnitRange{var"#s1"} where var"#s1"<:(AbstractUnitRange{var"#s2"} where var"#s2"<:Integer)) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513)
 (getindex(r::ArrayInterface.OptionallyStaticUnitRange, s::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/ranges.jl:296, getindex(r::AbstractUnitRange, s::OffsetArrays.IdOffsetRange) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513)
 (getindex(r::ArrayInterface.OptionallyStaticUnitRange, s::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/ranges.jl:296, getindex(r::AbstractUnitRange, s::Base.IdentityUnitRange{var"#s1"} where var"#s1"<:(AbstractUnitRange{var"#s2"} where var"#s2"<:Integer)) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513)
 (getindex(x::AbstractArray, ::AbstractTrees.ImplicitRootState) in AbstractTrees at /home/chriselrod/.julia/packages/AbstractTrees/oHb1F/src/iteration.jl:103, getindex(A::ArrayInterface.AbstractArray2, args...) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/ArrayInterface.jl:607)
 (getindex(x::ArrayInterface.LazyAxis, i::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/axes.jl:293, getindex(r::AbstractUnitRange, s::OffsetArrays.IdOffsetRange) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513)

julia> for (a1,a2) ∈ amb
           println(a1, "\n", a2, "\n")
       end
getindex(x::ArrayInterface.LazyAxis, i::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/axes.jl:293
getindex(r::AbstractUnitRange, s::Base.IdentityUnitRange{var"#s1"} where var"#s1"<:(AbstractUnitRange{var"#s2"} where var"#s2"<:Integer)) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513

getindex(r::ArrayInterface.OptionallyStaticUnitRange, s::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/ranges.jl:296
getindex(r::AbstractUnitRange, s::OffsetArrays.IdOffsetRange) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513

getindex(r::ArrayInterface.OptionallyStaticUnitRange, s::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/ranges.jl:296
getindex(r::AbstractUnitRange, s::Base.IdentityUnitRange{var"#s1"} where var"#s1"<:(AbstractUnitRange{var"#s2"} where var"#s2"<:Integer)) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513

getindex(x::AbstractArray, ::AbstractTrees.ImplicitRootState) in AbstractTrees at /home/chriselrod/.julia/packages/AbstractTrees/oHb1F/src/iteration.jl:103
getindex(A::ArrayInterface.AbstractArray2, args...) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/ArrayInterface.jl:607

getindex(x::ArrayInterface.LazyAxis, i::AbstractUnitRange{var"#s15"} where var"#s15"<:Integer) in ArrayInterface at /home/chriselrod/.julia/packages/ArrayInterface/CYf5x/src/axes.jl:293
getindex(r::AbstractUnitRange, s::OffsetArrays.IdOffsetRange) in OffsetArrays at /home/chriselrod/.julia/packages/OffsetArrays/EYLoR/src/OffsetArrays.jl:513

So:

1. (::ArrayInterface.LazyAxis)[i::Base.IdentityUnitRange]
2. (::ArrayInterface.OptionallyStaticUnitRange)[::OffsetArrays.IdOffsetrange]
3. (::ArrayInterface.OptionallyStaticUnitRange)[::Base.IdentityUnitRange]
4. (::ArrayInterface.AbstractArray2)[::AbstractTrees.ImplicitRootState]
5. (ArrayInterface.LazyAxis)[OffsetArrays.IdOffsetRange]

[johnnychen94]

This is partly due to a new type piracy in JuliaArrays/OffsetArrays.jl#244, a patch might need JuliaLang/julia#41224 merged first.

cc: @jishnub

[jishnub]

As a temporary fix perhaps OffsetArrays may limit its piracy to ranges defined in Base. That should fix this, and it's unlikely that packages specifically depend on this behavior for range types that that they define.