Toy Robot Challenge

Welcome to the Toy Robot Challenge!

Problem Description

• The application is a simulation of a toy robot moving on a square tabletop, of dimensions 5 units x 5 units
• There are no other obstructions on the table surface
• The robot is free to roam around the surface of the table, but must be prevented from falling to destruction
• Any movement that would result in the robot falling from the table must be prevented, however further valid movement commands must still be allowed

Create an application that can read in commands of the following form -

PLACE X,Y,F
MOVE
LEFT
RIGHT
REPORT

PLACE will put the toy robot on the table in position X,Y and facing NORTH, SOUTH, EAST or WEST.

The origin (0,0) can be considered to be the SOUTH WEST most corner.

The first valid command to the robot is a PLACE command, after that, any sequence of commands may be issued, in any order, including another PLACE command. The application should discard all commands in the sequence until a valid PLACE command has been executed.

MOVE will move the toy robot one unit forward in the direction it is currently facing.

LEFT and RIGHT will rotate the robot 90 degrees in the specified direction without changing the position of the robot.

REPORT will announce the X,Y and F of the robot. This can be in any form, but standard output is sufficient.

A robot that is not on the table can choose the ignore the MOVE, LEFT, RIGHT and REPORT commands.

Input can be from a file, or from standard input, as the developer chooses.

Provide test data to exercise the application.

Constraints

The toy robot must not fall off the table during movement. This also includes the initial placement of the toy robot. Any move that would cause the robot to fall must be ignored.

Example Input/Output

a) PLACE 0,0,NORTH
   MOVE
   REPORT
   Output: 0,1,NORTH

b) PLACE 0,0,NORTH
   LEFT
   REPORT
   Output: 0,0,WEST

c) PLACE 1,2,EAST
   MOVE
   MOVE
   LEFT
   MOVE
   REPORT
   Output: 3,3,NORTH

Installation

System requirements:

• Python 3.8.7 or above
• poetry

Install all dependencies with poetry install. It will also create a virtualenv for us to work on this project. Activate the virtualenv, if not yet already, by executing poetry shell.

You can also execute the program using Docker. If so you can build the images locally first before moving to the following sections. The images only need to be rebuilt if the dependencies change.

docker compose build

Run tests

pytest

Or if you don't want to install anything locally:

docker compose run test

Run the program

python -m toy_robot.main

Or using Docker:

docker compose run app

Ctrl-C to exit it when you're done.

Architecture Decision Records

All the important architectural decisions made are recorded at docs/arch/. They follow the format described in this article https://cognitect.com/blog/2011/11/15/documenting-architecture-decisions.