Broadcasting over `VectorOfArray` does not preserve type of parent array

[jlchan]

Describe the bug 🐞

Broadcasting a function over VectorOfArray(::StructArray{SVector}) does not preserve the StructArray{SVector} type of the parent array. Instead, it produces VectorOfArray(::Array{SVector})

Expected behavior

I expect broadcasting over VectorOfArray(::StructArray{SVector}) to create another VectorOfArray(::StructArray{SVector}).

Minimal Reproducible Example 👇

using RecursiveArrayTools, StructArrays, StaticArrays
x = StructArray{SVector{2, Float64}}((randn(2), randn(2)))
typeof(zero.(VectorOfArray(x))) # VectorOfArray{Float64, 2, Vector{SVector{2, Float64}}}

I would expect typeof(zero.(VectorOfArray(x))) to be the same as typeof(VectorOfArray).

Environment (please complete the following information):

• Output of using Pkg; Pkg.status()

julia> using Pkg; Pkg.status()
Status `/private/var/folders/jz/1v6mxm6s45x5xm3l8dsqbcbr0000gp/T/jl_NAnzZK/Project.toml`
  [731186ca] RecursiveArrayTools v3.27.3
  [90137ffa] StaticArrays v1.9.8
  [09ab397b] StructArrays v0.6.18

• Output of using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)

julia> using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)
Status `/private/var/folders/jz/1v6mxm6s45x5xm3l8dsqbcbr0000gp/T/jl_NAnzZK/Manifest.toml`
  [7d9f7c33] Accessors v0.1.38
  [79e6a3ab] Adapt v4.1.1
  [4fba245c] ArrayInterface v7.17.0
  [a33af91c] CompositionsBase v0.1.2
  [187b0558] ConstructionBase v1.5.8
  [9a962f9c] DataAPI v1.16.0
  [e2d170a0] DataValueInterfaces v1.0.0
  [ffbed154] DocStringExtensions v0.9.3
  [e2ba6199] ExprTools v0.1.10
⌃ [46192b85] GPUArraysCore v0.1.6
  [3587e190] InverseFunctions v0.1.17
  [82899510] IteratorInterfaceExtensions v1.0.0
  [1914dd2f] MacroTools v0.5.13
  [bac558e1] OrderedCollections v1.6.3
  [aea7be01] PrecompileTools v1.2.1
  [21216c6a] Preferences v1.4.3
  [3cdcf5f2] RecipesBase v1.3.4
  [731186ca] RecursiveArrayTools v3.27.3
  [ae029012] Requires v1.3.0
  [7e49a35a] RuntimeGeneratedFunctions v0.5.13
  [90137ffa] StaticArrays v1.9.8
  [1e83bf80] StaticArraysCore v1.4.3
  [09ab397b] StructArrays v0.6.18
  [2efcf032] SymbolicIndexingInterface v0.3.35
  [3783bdb8] TableTraits v1.0.1
  [bd369af6] Tables v1.12.0
  [56f22d72] Artifacts
  [2a0f44e3] Base64
  [ade2ca70] Dates
  [76f85450] LibGit2
  [8f399da3] Libdl
  [37e2e46d] LinearAlgebra
  [d6f4376e] Markdown
  [ca575930] NetworkOptions v1.2.0
  [de0858da] Printf
  [9a3f8284] Random
  [ea8e919c] SHA v0.7.0
  [9e88b42a] Serialization
  [2f01184e] SparseArrays v1.10.0
  [10745b16] Statistics v1.10.0
  [fa267f1f] TOML v1.0.3
  [cf7118a7] UUIDs
  [4ec0a83e] Unicode
  [e66e0078] CompilerSupportLibraries_jll v1.1.1+0
  [e37daf67] LibGit2_jll v1.6.4+0
  [29816b5a] LibSSH2_jll v1.11.0+1
  [c8ffd9c3] MbedTLS_jll v2.28.2+1
  [4536629a] OpenBLAS_jll v0.3.23+4
  [bea87d4a] SuiteSparse_jll v7.2.1+1
  [8e850b90] libblastrampoline_jll v5.11.0+0
Info Packages marked with ⌃ have new versions available and may be upgradable.

• Output of versioninfo()

julia> versioninfo()
Julia Version 1.10.6
Commit 67dffc4a8ae (2024-10-28 12:23 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: macOS (arm64-apple-darwin24.0.0)
  CPU: 12 × Apple M2 Max
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-15.0.7 (ORCJIT, apple-m1)
Threads: 8 default, 0 interactive, 4 GC (on 8 virtual cores)
Environment:
  JULIA_EDITOR = code
  JULIA_NUM_THREADS = 8

Additional context

Related to trixi-framework/Trixi.jl#2150

[huiyuxie]

Could you please point me to the specific errors this bug might cause in Trixi.jl (simple description is also fine)?

[huiyuxie]

cc @ChrisRackauckas

[jlchan]

It is this specific elixir, but I am unsure of why this issue would impact that test and not others.

We have other tests where we use VoA wrappers around StructArrays (for example this) and those examples don't fail with the same error.

[jlchan]

I think this issue would still be nice to resolve, but I don't think it's what's causing some failing tests in trixi-framework/Trixi.jl#2150, so no rush on addressing this.

[ChrisRackauckas]

Well it's what I had open while on a flight so it's done now

[jlchan]

Thank you!