perfect-numbers: stub implementation passes all tests

[ErikSchierboom]

If I use the following stub implementation, all tests pass:

function isperfect(n)
    n > 0 || throw(DomainError(n, "Must be positive"))
end

function isabundant(n)
    n > 0 || throw(DomainError(n, "Must be positive"))
end

function isdeficient(n)
    n > 0 || throw(DomainError(n, "Must be positive"))
end

[depial]

Below, I've modified runtests.jl by adding two tests for each of isperfect, isabundant and isdeficient which should return false. I simply used one number from each of the other two kinds of numbers for each function, which is enough to invalidate implementations like the stub above.

using Test

include("perfect-numbers.jl")

@testset "Perfect numbers" begin

    @testset "Smallest perfect number is classified correctly" begin
        @test isperfect(6)
    end

    @testset "Medium perfect number is classified correctly" begin
        @test isperfect(28)
    end

    @testset "Large perfect number is classified correctly" begin
        @test isperfect(33550336)
    end

    @testset "Correctly handles non-perfect numbers" begin
        @test !isperfect(12)
        @test !isperfect(4)
    end
end

@testset "Abundant numbers" begin

    @testset "Smallest abundant number is classified correctly" begin
        @test isabundant(12)
    end

    @testset "Medium abundant number is classified correctly" begin
        @test isabundant(30)
    end

    @testset "Large abundant number is classified correctly" begin
        @test isabundant(33550335)
    end

    @testset "Correctly handles non-abundant numbers" begin
        @test !isabundant(6)
        @test !isabundant(32)
    end
end

@testset "Deficient numbers" begin

    @testset "Smallest prime deficient number is classified correctly" begin
        @test isdeficient(2)
    end

    @testset "Smallest non-prime deficient number is classified correctly" begin
        @test isdeficient(4)
    end

    @testset "Medium deficient number is classified correctly" begin
        @test isdeficient(32)
    end

    @testset "Large deficient number is classified correctly" begin
        @test isdeficient(33550337)
    end

    @testset "Edge case (no factors other than itself) is classified correctly" begin
        @test isdeficient(1)
    end

    @testset "Correctly handles non-deficient numbers" begin
        @test !isdeficient(28)
        @test !isdeficient(30)
    end
end

@testset "Invalid inputs" begin

    @testset "Zero is rejected (not a natural number)" begin
        @test_throws DomainError isdeficient(0)
        @test_throws DomainError isperfect(0)
        @test_throws DomainError isabundant(0)
    end

    @testset "Negative integer is rejected (not a natural number)" begin
        @test_throws DomainError isdeficient(-1)
        @test_throws DomainError isperfect(-1)
        @test_throws DomainError isabundant(-1)
    end
end

[ErikSchierboom]

@depial Great. Would you be willing to submit a PR?

[depial]

@ErikSchierboom The PR can be found here. Sorry I didn't open it directly, but I wasn't aware of the process of creating a branch from my fork to submit a PR with just a single commit.

A side note: the Exercise CI / Julia nightly - OS (pull_request) checks are failing due to what appears to be a problem with Circular Buffer (specifically the isfull method).

[ErikSchierboom]

A side note: the Exercise CI / Julia nightly - OS (pull_request) checks are failing due to what appears to be a problem with Circular Buffer (specifically the isfull method).

Hmmm, interesting. Would you be willing to take a look at that too?

[depial]

I've found a quick fix for the nightly check issue in this PR, and all checks pass now, but I feel like there's something deeper to it since it seems to have appeared from nowhere a couple of weeks ago (Bump Actions showing the first failure here).

[ErikSchierboom]

I've merged that PR. Could you rebase this PR?

[depial]

Everything should be synced now