Vinai / space48-module-master-mind

Training module to practice testing in the context of Magento 2.

MasterMind

This module implements a simple variant of the game MasterMind.
The purpose of this module is to practice testing in the context of Magento 2 module development.

How to install

Run the following composer commands in the Magento 2 root directory:

$ composer config repositories.mastermind-exercise git [e-mail]:Vinai/space48-module-master-mind.git
$ composer require space48/module-mastermind:dev-master

How to play

To play in the browser visit the module page at http://[magento base url]/mastermind, or
to play on the console, run bin/magento play:mastermind.

How to use

The purpose of this module is to allow practicing different aspects of testing related to Magento 2 module development.

The repository has 4 tags:

• 0-complete: The fully functional module. Same as the HEAD of the master branch. Use this as a reference.
• 1-no-guess-checker: The complete module missing only the Model\GuessCheckerInterface implementation.
• 2-no-mastermind: The complete module, except for the Model\GuessCheckerInterface and the Model\MasterMindGameInterface implementations.
• 3-no-evaluate-action: The complete module, except for the Model\GuessCheckerInterface, the Model\MasterMindGameInterface and the \Space48\MasterMind\Controller\Evaluate\Index implementations.

Depending on the available time, run git checkout [tag-name] and implement the missing classes. Each of 3 classes that can be implemented allows practicing different aspects related to testing.

\Space48\MasterMind\Model\GuessCheckerInterface

GuessCheckerInterface::check(string[] $targetColors, string[] $guessColors): string

Compares the guess colors with the target colors and returns the value of one of the constants:

1. self::PERFECT if all colors and positions match in both arrays.
2. self::ONE_CORRECT_POSITION if one of the guess colors matches the position in the target colors.
3. self::ONE_WRONG_POSITION if one of the guess colors matches but not in the same position.
4. self::NO_MATCH if no guess color matches a target color.

The purpose of this class is to practice testing a pure function without collaborators.
Find examples to test all possible results. No test doubles are required.

\Space48\MasterMind\Model\MasterMindGameInterface

MasterMindGameInterface::playerGuesses(string[] $colors): mixed[]

This method is responsible for coordinating the game round.

Receives the player guess as an array of color strings.

1. If no target colors are set, pick the target colors.

2. Check the guess, and return an array with the check result and also the guess count for the current game.

   Example return array structure:

   [
       self::KEY_CHECK_RESULT => GuessCheckerInterface::NO_MATCH,
       self::KEY_GUESS_COUNT  => 5
   ]

3. If the check result is GuessCheckerInterface::PERFECT, reset the game state before returning.

4. Each call to playerGuesses() increments the guess count for the current game.

The following classes should be used as collaborators:

• \Space48\MasterMind\Model\GameStateInterface (target colors, guess count, reset game state)
• \Space48\MasterMind\Model\GuessCheckerInterface (compare guess to target colors)
• \Space48\MasterMind\Config\Colors (pick new target colors)

The purpose of this class is to practice testing while replacing the collaborators with test doubles (a.k.a. "mocks").
Finding all required example test cases is an important part of the task.

\Space48\MasterMind\Controller\Evaluate\Index

Index::execute(): Magento\Framework\Controller\Result\Json

Retrieves the player guess from the request, passes it to MasterMindGameInterface::playerGuesses(), builds a string from the returned message and guess count, and finally returns that string as a JSON response.

The purpose of this class is to practice testing a class extending a layer supertype (a class extending an abstract M2 core class) using integration tests.

Copyright:

(c) Vinai Kopp 2017