React tutorial from https://reactjs.org/tutorial/tutorial.html

Just following the tutorial and writing Cypress component tests.

## Tic-tac-toe

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The example code taken from [https://codepen.io/gaearon/pen/LyyXgK](https://codepen.io/gaearon/pen/LyyXgK)

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Test | Description
--- | ---
[square-spec.js](square-spec.js) | Testing individual square
[tic-tac-toe-spec.js](tic-tac-toe-spec.js) | Testing the entire game
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![Tic tac toe](images/tic-tac-toe.gif)

For larger Tic-Tac-Toe example with mocking, read the blog post [Tic-Tac-Toe Component Tests](https://glebbahmutov.com/blog/tic-tac-toe-component-tests/)
