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Mastering React Test-Driven Development

You're reading from   Mastering React Test-Driven Development Build rock-solid, well-tested web apps with React, Redux and GraphQL

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Product type Paperback
Published in May 2019
Publisher Packt
ISBN-13 9781789133417
Length 496 pages
Edition 1st Edition
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Author (1):
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Daniel Irvine Daniel Irvine
Author Profile Icon Daniel Irvine
Daniel Irvine
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Toc

Table of Contents (21) Chapters Close

Preface 1. Section 1: First Principles of TDD FREE CHAPTER
2. First Steps with Test-Driven Development 3. Test-driving Data Input with React 4. Exploring Test Doubles 5. Creating a User Interface 6. Section 2: Building a Single-Page Application
7. Humanizing Forms 8. Filtering and Searching Data 9. Test-driving React Router 10. Test-driving Redux 11. Test-driving GraphQL 12. Section 3: Interactivity
13. Building a Logo Interpreter 14. Adding Animation 15. Working with WebSockets 16. Section 4: Acceptance Testing with BDD
17. Writing Your First Acceptance Test 18. Adding Features Guided by Acceptance Tests 19. Understanding TDD in the Wider Testing Landscape 20. Other Books You May Enjoy

Performing client-side validation

The Git tag for this section is client-side-validation.

As our users fill out our forms, we want to alert them to any issues as soon as possible. We'll alert the user to any validation issues once the focus is no longer on the text field, using the blur event.

We will represent validation errors as strings within a validationErrors object that's stored as component state. We can use this object to help us validate each field within the form. Each field has a key in the object. An undefined value (or absence of a value) represents no validation error, and a string value represents an error. Here's an example:

{
validationErrors: {
firstName: 'First name is required',
lastName: undefined,
phoneNumber: 'Phone number must contain only numbers, spaces, and any of the following: + - ( ) .'
}
}
Validation...
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