I havne't been able to replicate it in CI, but I have replicated it on both a M1 Mac and and an x86-64 Ubuntu machine locally:
BoundsError: attempt to access 3-element CategoricalArrays.CategoricalRefPool{Union{Missing, CategoricalValue{String, UInt32}}, CategoricalPool{String, UInt32}} with indices 0:2 at index [3]
cc @nalimilan
Details
```julia
# some dict encoding coverage: Error During Test at /home/ubuntu/arrow-julia/test/runtests.jl:339
Got exception outside of a @test
BoundsError: attempt to access 3-element CategoricalArrays.CategoricalRefPool{Union{Missing, CategoricalValue{String, UInt32}}, CategoricalPool{String, UInt32}} with indices 0:2 at index [3]
Stacktrace:
[1] throw_boundserror(A::CategoricalArrays.CategoricalRefPool{Union{Missing, CategoricalValue{String, UInt32}}, CategoricalPool{String, UInt32}}, I::Tuple{Int64})
@ Base ./abstractarray.jl:737
[2] checkbounds
@ ./abstractarray.jl:702 [inlined]
[3] getindex
@ ~/.julia/packages/CategoricalArrays/ptzwC/src/array.jl:1161 [inlined]
[4] getindex
@ ~/.julia/packages/ArrowTypes/IVpuP/src/ArrowTypes.jl:445 [inlined]
[5] iterate
@ ./abstractarray.jl:1216 [inlined]
[6] Arrow.ValidityBitmap(x::ToArrow{Union{Missing, String}, CategoricalArrays.CategoricalRefPool{Union{Missing, CategoricalValue{String, UInt32}}, CategoricalPool{String, UInt32}}})
@ Arrow ~/arrow-julia/src/arraytypes/arraytypes.jl:228
[7] arrowvector(::ListKind{true}, x::ToArrow{Union{Missing, String}, CategoricalArrays.CategoricalRefPool{Union{Missing, CategoricalValue{String, UInt32}}, CategoricalPool{String, UInt32}}}, i::Int64, nl::Int64, fi::Int64, de::Dict{Int64, Any}, ded::Vector{Arrow.DictEncoding}, meta::Base.ImmutableDict{String, String}; largelists::Bool, kw::@kwargs{dictencode::Bool, maxdepth::Int64, dictencodenested::Bool, compression::Nothing})
@ Arrow ~/arrow-julia/src/arraytypes/list.jl:226
[8] arrowvector
@ ~/arrow-julia/src/arraytypes/list.jl:224 [inlined]
[9] #arrowvector#10
@ ~/arrow-julia/src/arraytypes/arraytypes.jl:150 [inlined]
[10] arrowvector
@ ~/arrow-julia/src/arraytypes/arraytypes.jl:148 [inlined]
[11] arrowvector(x::CategoricalArrays.CategoricalRefPool{Union{Missing, CategoricalValue{String, UInt32}}, CategoricalPool{String, UInt32}}, i::Int64, nl::Int64, fi::Int64, de::Dict{Int64, Any}, ded::Vector{Arrow.DictEncoding}, meta::Nothing; dictencoding::Bool, dictencode::Bool, maxdepth::Int64, kw::@kwargs{dictencodenested::Bool, compression::Nothing})
@ Arrow ~/arrow-julia/src/arraytypes/arraytypes.jl:113
[12] arrowvector(::DictEncodedKind, x::Arrow.DictEncode{Union{Missing, CategoricalValue{String, UInt32}}, CategoricalVector{Union{Missing, String}, UInt32, String, CategoricalValue{String, UInt32}, Missing}}, i::Int64, nl::Int64, fi::Int64, de::Dict{Int64, Any}, ded::Vector{Arrow.DictEncoding}, meta::Base.ImmutableDict{String, String}; dictencode::Bool, dictencodenested::Bool, kw::@kwargs{maxdepth::Int64, compression::Nothing})
@ Arrow ~/arrow-julia/src/arraytypes/dictencoding.jl:236
[13] arrowvector
@ ~/arrow-julia/src/arraytypes/dictencoding.jl:202 [inlined]
[14] #arrowvector#10
@ ~/arrow-julia/src/arraytypes/arraytypes.jl:150 [inlined]
[15] arrowvector
@ ~/arrow-julia/src/arraytypes/arraytypes.jl:148 [inlined]
[16] arrowvector(x::CategoricalVector{Union{Missing, String}, UInt32, String, CategoricalValue{String, UInt32}, Missing}, i::Int64, nl::Int64, fi::Int64, de::Dict{Int64, Any}, ded::Vector{Arrow.DictEncoding}, meta::Nothing; dictencoding::Bool, dictencode::Bool, maxdepth::Int64, kw::@kwargs{compression::Nothing})
@ Arrow ~/arrow-julia/src/arraytypes/arraytypes.jl:113
[17] arrowvector
@ ~/arrow-julia/src/arraytypes/arraytypes.jl:68 [inlined]
[18] toarrowvector(x::CategoricalVector{Union{Missing, String}, UInt32, String, CategoricalValue{String, UInt32}, Missing}, i::Int64, de::Dict{Int64, Any}, ded::Vector{Arrow.DictEncoding}, meta::Nothing; compression::Nothing, kw::@kwargs{})
@ Arrow ~/arrow-julia/src/arraytypes/arraytypes.jl:47
[19] toarrowvector
@ ~/arrow-julia/src/arraytypes/arraytypes.jl:36 [inlined]
[20] toarrowvector(x::CategoricalVector{Union{Missing, String}, UInt32, String, CategoricalValue{String, UInt32}, Missing})
@ Arrow ~/arrow-julia/src/arraytypes/arraytypes.jl:36
[21] macro expansion
@ ~/arrow-julia/test/runtests.jl:347 [inlined]
[22] macro expansion
@ ~/.julia/juliaup/julia-1.10.10+0.x64.linux.gnu/share/julia/stdlib/v1.10/Test/src/Test.jl:1577 [inlined]
[23] macro expansion
@ ~/arrow-julia/test/runtests.jl:341 [inlined]
[24] macro expansion
@ ~/.julia/juliaup/julia-1.10.10+0.x64.linux.gnu/share/julia/stdlib/v1.10/Test/src/Test.jl:1577 [inlined]
[25] macro expansion
@ ~/arrow-julia/test/runtests.jl:115 [inlined]
[26] macro expansion
@ ~/.julia/juliaup/julia-1.10.10+0.x64.linux.gnu/share/julia/stdlib/v1.10/Test/src/Test.jl:1577 [inlined]
[27] top-level scope
@ ~/arrow-julia/test/runtests.jl:54
[28] include(fname::String)
@ Base.MainInclude ./client.jl:494
[29] top-level scope
@ none:6
[30] eval
@ ./boot.jl:385 [inlined]
[31] exec_options(opts::Base.JLOptions)
@ Base ./client.jl:296
[32] _start()
@ Base ./client.jl:557
```
