Improve transpose, adjoint of vector StridedView

[mtfishman]

Hi @Jutho, this makes it so that transpose and adjoint of vector StridedView remains a StridedView.

I did this by generalizing transpose and adjoint to support both matrix and vector StridedView by calling permutedims(::StridedView), and then making sure that works for vector StridedView by calling sreshape (so this PR also fixes permutedims(::StridedView) for vector StridedView as well). Open to other approaches.

[Jutho]

I am a bit hesitant about this. This means that transpose(v) * v no longer yields a number, which was the whole point why the Transpose objects were created in Julia Base. While the transpose behaviour is not officially specified in the AbstractArray interface, I do feel like this constitutes a violation of the AbstractArray interface that I would prefer to avoid.

[mtfishman]

Oh good point, I hadn't considered that usage of transpose/adjoint.

[Jutho]

I think adding these lines below line 172 would also resolve your issue:

function sreshape(a::LinearAlgebra.AdjointAbsVec, newsize::Dims)
    return sreshape(conj(StridedView(adjoint(a))), newsize)
end
function sreshape(a::LinearAlgebra.TransposeAbsVec, newsize::Dims)
    return sreshape(StridedView(transpose(a)), newsize)
end

[Jutho]

From CI, it seems like I will also have to check what is going on with Aqua.jl ?

[mtfishman]

That looks like a good fix, thanks. I can update this PR with that fix and look into the Aqua issue.

[Jutho]

That would be great, it's getting a bit late here to focus and do stuff properly. Feel free to bump the patch version while you are at it, then I can merge tomorrow morning if all lights turn green and immediately register the new version.

[mtfishman]

Ok, I changed it over to your fix, updated the tests, and updated to the latest Aqua syntax (I just removed the project_toml_formatting keyword argument since it was removed in JuliaTesting/Aqua.jl#209).

Looks like the CI needs your approval to run.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (00be762) 93.52% compared to head (feefe73) 93.67%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main       #5      +/-   ##
==========================================
+ Coverage   93.52%   93.67%   +0.14%     
==========================================
  Files           4        4              
  Lines         170      174       +4     
==========================================
+ Hits          159      163       +4     
  Misses         11       11              

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