How to use a previous version of the Statistics or Linear Algebra Package from the Standard Library

I added a model called GEKPLS.jl to the Surrogates package a few months ago. GEKPLS uses the Linear Algebra and Statistics packages from the standard library.

A few weeks ago, a few tests started failing without any changes having been made to the file. My current hypothesis is that the issue is a result of some upstream changes made sometime after Oct. 25 (when all tests were passing). In trying to debug this issue, I am trying to test with previous versions of the statistics and linear algebra packages. However, when I check for the package versions, I’m not able to see the package versions:


(Surrogates) pkg> status Statistics
     Project Surrogates v6.4.0
      Status `~/Documents/julia-projects/Surrogates.jl/Project.toml`
  [10745b16] Statistics

(Surrogates) pkg> status LinearAlgebra
     Project Surrogates v6.4.0
      Status `~/Documents/julia-projects/Surrogates.jl/Project.toml`
  [37e2e46d] LinearAlgebra

Is there a way to switch back to previous versions of these packages so that I can get back to the original state when everything was working fine?

Also, do you have any advice or ideas on how I can begin to debug this issue?

Since they are bundled with Julia you can just install an older version of Julia. The only Julia release after Oct 25 is 1.8.3, so perhaps you can go back and try with 1.8.2.