Homework 4

In this homework you will extend the Diet trait from the lab by omnivores and make the Ecosystem.jl package pass automated quality checks. Start from your package from the lab, including the Diet trait with Herbivore and Carnivore.

How to submit?

Zip the whole package folder Ecosystem.jl and upload it to BRUTE. The package has to include at least the following files:

├── Project.toml
├── src
│   └── Ecosystem.jl
└── test
    ├── diet.jl      # testsets for the Diet trait
    └── runtests.jl  # includes diet.jl and runs Aqua

The test/runtests.jl file can look like this:

using Test
using Aqua
using Ecosystem

include("diet.jl")

@testset "Aqua" begin
    Aqua.test_all(Ecosystem)
end

Omnivores

Homework

1. Add a new trait value Omnivore <: Diet. An omnivore eats

   • plants with size > 0 (like a herbivore),

   • animals whose species is a Herbivore (like a carnivore).

2. Add a new species Bear <: AnimalSpecies with the diet Omnivore. Use the same constructor pattern as for Sheep and Wolf, e.g. Bear(id; E=20.0, ΔE=4.0, pr=0.05, pf=0.3, s=randsex()), and print it as 🐻.

3. Export Omnivore and Bear.

4. eats and eat! have to work for all combinations of species, following the table:

eats ↓ \ food →	Grass	Sheep	Wolf	Bear
Sheep	✔
Wolf		✔
Bear	✔	✔

When a bear eats grass, it behaves like a sheep eating grass. When a bear eats a sheep, it behaves like a wolf eating a sheep.

HINTS:

• Do not modify the methods for Herbivore and Carnivore. Can you reuse them for Omnivore?

• Do carnivores eat bears? Check that your rule for carnivores does not need to change.

Tests and quality checks

Homework

1. Write test/diet.jl with testsets that check the whole table above using eats, and check that

   • a Bear eating fully grown Grass sets its size to 0,

   • a Bear eating a Sheep removes the sheep from the World.

2. Add Aqua.jl as a test dependency of the package and make Aqua.test_all(Ecosystem) pass.

HINTS:

• Test dependencies go to [extras] and [targets] in Project.toml (or to test/Project.toml), see the bachelor course.

• Aqua requires [compat] entries for all dependencies, including julia and the test dependencies (Aqua, Test).

• Aqua checks method ambiguities. If you get one for eats or eat!, which methods are equally specific?

• ]test has to pass in a fresh Julia session.

Show solution

Nothing to see here.