Zygote ext

[vpuri3]

part of #215

ref https://pkgdocs.julialang.org/dev/creating-packages/#Conditional-loading-of-code-in-packages-(Extensions)

[vpuri3]

running CI with dummy change since tests were failing locally.

[codecov]

Codecov Report

Patch coverage: 10.52% and project coverage change: +0.10 🎉

Comparison is base (c2bbf98) 0.21% compared to head (21a9a1e) 0.31%.

Additional details and impacted files

@@            Coverage Diff            @@
##           master    #218      +/-   ##
=========================================
+ Coverage    0.21%   0.31%   +0.10%     
=========================================
  Files          15      14       -1     
  Lines         936     940       +4     
=========================================
+ Hits            2       3       +1     
- Misses        934     937       +3     

Impacted Files	Coverage Δ
ext/SparseDiffToolsZygote.jl	0.00% <0.00%> (ø)
src/SparseDiffTools.jl	37.50% <50.00%> (-2.50%)	⬇️

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[vpuri3]

@ChrisRackauckas looks like SparseDiffTools needs more comprehensive testing. I am getting arrayinerface errors with 1.9 on my personal machine that are not captured on CI.

[vpuri3]

Looks like package extension don't honor export statements. Rather, it is just

julia> versioninfo()
Julia Version 1.9.0-rc1
Commit 3b2e0d8fbc1 (2023-03-07 07:51 UTC)

(a) pkg> st                                                                          
Status `~/.julia/dev/SparseDiffTools/a/Project.toml`
  [47a9eef4] SparseDiffTools v2.0.0 `..`
  [e88e6eb3] Zygote v0.6.56                                                          
                                          
julia> using SparseDiffTools, Zygote  
[ Info: Precompiling SparseDiffToolsZygote [25f82377-10ae-5fb8-bc0d-27fd31de4285]
                                          
julia> m = Base.get_extension(SparseDiffTools, :SparseDiffToolsZygote)
SparseDiffToolsZygote 

julia> m.ZygoteVecJac
ZygoteVecJac (generic function with 1 method)

julia> ZygoteVecJac
ERROR: UndefVarError: `ZygoteVecJac` not defined

julia> SparseDiffTools.ZygoteVecJac
ERROR: UndefVarError: `ZygoteVecJac` not defined
Stacktrace:
 [1] getproperty(x::Module, f::Symbol)

So I think we should define and export these symbols in the main package, and write method definitions in the extension.

[vpuri3]

@ChrisRackauckas can you merge #220 so we can test for 1x9 here?

[vpuri3]

rerunning CI

[vpuri3]

@ChrisRackauckas good to go