Ad-hoc equality test for struct after definition

General Usage
12

Just for the sake of it. This is what has gone into my runtests.jl for checking whether two structs are the same (or nearly the same if they have Floats). It’s ugly, doesn’t cover all types, but it only takes a few μs to run. (You don’t need to initialize test outside the function anymore.

function chkFieldNames!(x::S, y::T, icount=0, depth=0; test::Vector{Bool} = Vector{Bool}(undef,0), max_call=50) where {S, T}
    atol = 1e-5 # Resisted temptation to make an argument that is recursively passed around.
    if icount == 0 && depth == 0
        global test = Vector{Bool}(undef,0)
        println("Test initialised")
    end
    tx = typeof(x)
    ty = typeof(y)
    if tx == ty && depth < max_call
        for i in fieldnames(tx)  
            gx = getfield(x, i)
            gy = getfield(y, i)
            tgx = typeof(gx)
            if isprimitivetype(tgx)
                #println("Primitive type: ", tgx)
                if tgx <: AbstractFloat
                    push!(test, isapprox(gx, gy, atol=atol))
                else
                    push!(test, gx == gy)
                end
            elseif tgx <: AbstractArray
                #println("AbstractArray type: ", tgx)
                if ndims(gx) == ndims(gy)
                    push!(test, isapprox(gx, gy, atol=atol))
                else
                    push!(test, 0)
                end
            elseif tgx <: String
                #println("String type: ", tgx)
                push!(test, gx == gy)
            else
                depth += 1
                #icount != 0 || depth == 1 && println("Non-primitive type: ", tgx)
                chkFieldNames!(gx, gy, icount, depth, test=test)
            end
        end
    else
        if depth >= max_call 
            @warn "Run-away search -- self referential types?"
            return test
        else μ
            println("Unequal types: ", tx, " and ", ty)
            push!(test, 0)
        end
    end
    icount += length(test)
    #icount != 0 && println("Count = ", icount)
    return test
end