Toy Robot Simulator

Instruction

This application is implemented in JavaScript based on Node.js.

Here is the detail of my coding environment:

OS: Windows 10
IDE: VS Code
Node.js Version: v10.13.0 (LTS 'Dubnium')
App entry: main.js

Input is from standard input. In order to run this application, go to Terminal and cd to the root directory, and then run node main.js

cd /YOUR_PATH_TO/robot/
node main.js

When you see a greeting message then you can start to type in command and enter (one command per line). The application will continue to receive command until you manually terminate the process (ctrl + c).

Thoughts

1. I utilised Command Pattern to implement this application, not only because the behavour of this problem fits well, but also providing potentials to further extension (undo feature, new commands, new way of inputting commands and etc.)

2. Test cases down below are summarised from the instruction of this problem and need to be tested manually, which can be improved. A more comprehensive approach could be writing proper user stories based on requirement in advance, and coding up unit test/behaviour test to automatically test the app.

Test Cases

Combined Example a, b, c from problem instruction

PLACE 0,0,NORTH
MOVE
REPORT
PLACE 0,0,NORTH
LEFT
REPORT
PLACE 1,2,EAST
MOVE
MOVE
LEFT
MOVE
REPORT

Expected output:

0,1,NORTH
0,0,WEST
3,3,NORTH

Prevent falling however allow further valid movement command

PLACE 100,100,NORTH
REPORT
PLACE 4,4,EAST
MOVE
REPORT
LEFT
MOVE
REPORT
PLACE 0,0,WEST
MOVE
REPORT
LEFT
MOVE
REPORT

Expected output:

4,4,EAST
4,4,NORTH
0,0,WEST
0,0,SOUTH

Discard all commands in the sequence until a valid PLACE command has been executed

LEFT
RIGHT
MOVE
PLACE 100,100,NORTH
REPORT
PLACE 0,0,NORTH
REPORT

Expected output:

0,0,NORTH