reduce(hcat,v) fails for offset v with vector eltype

[yha]

On Julia 1.5.1:

julia> using OffsetArrays

julia> reduce(hcat, OffsetVector([1:2, 1:2],10))
ERROR: BoundsError: attempt to access 2-element Array{UnitRange{Int64},1} at index [-9]

[johnnychen94]

This is not supported yet.

See also: JuliaArrays/OffsetArrays.jl#63

[yha]

See also: JuliaArrays/OffsetArrays.jl#63

That seems to be a different issue, as the vectors being concatenated (arguments to hcat) have offsets, whereas the current issue is about the argument to reduce having an offset.
Since reduce is defined for a general iterator, it shouldn't matter what the input axes of its second argument are, only what it returns when iterated.
EDIT: the original example was bad, because it should also fail for a different reason. I edited it now. This should clarify the problem:

julia> reduce(hcat, [1:2, 1:2])
2×2 Array{Int64,2}:
 1  1
 2  2

julia> reduce(hcat, OffsetVector([1:2, 1:2], 10)) # should return the same result
ERROR: BoundsError: attempt to access 2-element Array{UnitRange{Int64},1} at index [-9]

EDIT 2: a possible workaround is directly invoking the general method:

julia> invoke(reduce, Tuple{Any,Any}, hcat, OffsetVector([1:2,1:2],10))
2×2 Array{Int64,2}:
 1  1
 2  2