`getindex` too relaxed on reinterpreted array

[Moelf]

julia> a=[1,2,3]
3-element Vector{Int64}:
 1
 2
 3

julia> a[]
ERROR: BoundsError: attempt to access 3-element Vector{Int64} at index []
Stacktrace:
 [1] throw_boundserror(A::Vector{Int64}, I::Tuple{})
   @ Base ./essentials.jl:14
 [2] checkbounds
   @ ./abstractarray.jl:699 [inlined]

julia> reinterpret(UInt8, a)[]
0x01

the last line should error as well

[gbaraldi]

julia/base/reinterpretarray.jl

Line 394 in a690758

@propagate_inbounds getindex(a::ReinterpretArray) = a[firstindex(a)]

[adienes]

but... why? I mean it was clearly intentional but isn't it a bug?

[Moelf]

yeah I know where the line comes from, but I think that's a bug right?

[nsajko]

Historic behavior when running [10, 20][]:

• v0.6.4: succeeds, returning the first element
• v0.7.0: this deprecation warning is produced:

  ┌ Warning: omitting indices for non-singleton trailing dimensions is deprecated. Add `1` as trailing indices or use `reshape` to make the dimensionality of the array match the number of indices.
  │   caller = top-level scope at none:0
  └ @ Core none:0
  

• v1: throws BoundsError

So I guess the ReinterpretArray method is simply left over from the pre-v0.7 days, that is, someone forgot to adjust it when updating the indexing behavior for AbstractArray?