Unable to to detect unbounded type parameters enclosed in `Type`

[frankwswang]

Define a minimal module in AquaTest.jl:

module AquaTest

export get_ele_T

get_ele_T(::Type{<:Array{T}}) where {T} = T

end

Then run the following code in REPL started in the same directory:

julia> begin
           push!(LOAD_PATH, ".")
           using AquaTest
           using Aqua
       end

julia> Aqua.test_unbound_args(AquaTest)
Test Passed

julia> get_ele_T(Union{})
ERROR: UndefVarError: `T` not defined in static parameter matching
Suggestion: run Test.detect_unbound_args to detect method arguments that do not fully constrain a type parameter.

It seems that Aqua.jl (v0.8.12) ignored the edge case of Union{} isa Type{<:Array{T}} where {T}.

[lgoettgens]

Thanks for your report. Unfortunately, this test is not implemented in Aqua.jl, but we instead call Test.detect_unbound_args from the julia Test stdlib.
I created an upstream issue as JuliaLang/julia#58539.