This is the result of me following The Raytracer Challenge by Jamis Buck. It is an excellent book to get along in building a Raytracer from scratch. As the book is language agnostic, I decided to use it to learn Rust.
The book encourages a Test-Driven Development (TDD) approach, for which Rust conveniently has built-in tooling.
To run tests from the command-line, just run
cargo test