Is there a difference under the hood between running code via a .jl file and running code via `test name_of_pkg`?

Hey all,

I am running into a weird issue. I have some code which I will arbitrarily say is:

function z()
   z = 10
   z += 100
end
z()
# This code will work, it's just an arbitrary example. 

When I have the above code in a random “.jl” file and I run it, there are no issues. However, when I move the code into my “runtests.jl” file and then do test PkgName, I get an error.

Is there some difference under the hood in the way the code is run usually vs the way it is run when testing a package through the Repl?

There are a couple differences: Pkg.test spawns a new process to run the tests in, and starts the process with --check-bounds=yes and --startup-file=no (see 12. API Reference · Pkg.jl). I believe on master also Julia will not show deprecation warnings by default (https://github.com/JuliaLang/julia/pull/35362), but Pkg.test will pass --depwarn=yes to enable them.

An other difference has to do with dependencies: Pkg.test will run the tests in an “environment stack” that does not include the “default environment” (I’m actually not sure how to call it; it’s the environment that’s named after the Julia version and which is active by default).

In contrast, the REPL runs by default in a composite environment where the environment of the currently active project is stacked with the default environment, as determined by LOAD_PATH:

julia> LOAD_PATH
3-element Array{String,1}:
 "@"       # currently active project
 "@v#.#"   # default environment
 "@stdlib" # standard library

This means that if you code makes use of some package that has been Pkg.added to the default environment, but not declared as a dependency of the current project, Pkg.test will catch that.

Ah, that reminds me as well that the standard library InteractiveUtils is loaded automatically in the REPL, but isn’t loaded with Pkg.test.

Thanks all! It ended up being that I was using a relative file path and being one folder deeper (in the test folder) messed things up :slight_smile: