Simplify Testing with React Testing Library

Create maintainable tests using RTL that do not break with changes

Author: Scottie Crump

Publisher: Packt Publishing Ltd

ISBN:

Category: Computers

Page: 246

View: 188

A fast-paced, practical guide to helping you leverage React Testing Library to test the DOM output of components Key Features Get to grips with React Testing Library and create tests that don't break with changes in implementation Learn how to put RTL into practice by implementing it in real-world scenarios Test apps to be more accessible and ensure your tests will work with actual DOM nodes Book Description React Testing Library (RTL) is a lightweight and easy-to-use tool for testing the document object model (DOM) output of components. This book will show you how to use this modern, user-friendly tool to test React components, reducing the risk that your application will not work as expected in production. The book demonstrates code snippets that will allow you to implement RTL easily, helping you to understand the guiding principles of the DOM Testing Library to write tests from the perspective of the user. You'll explore the advantages of testing components from the perspective of individuals who will actually use your components, and use test-driven development (TDD) to drive the process of writing tests. As you advance, you'll discover how to add RTL to React projects, test components using the Context API, and also learn how to write user interface (UI) end-to-end tests using the popular Cypress library. Throughout this book, you'll work with practical examples and useful explanations to be able to confidently create tests that don't break when changes are made. By the end of this React book, you will have learned all you need to be able to test React components confidently. What you will learn Explore React Testing Library and its use cases Get to grips with the RTL ecosystem Apply jest-dom to enhance your tests using RTL Gain the confidence you need to create tests that don't break with changes using RTL Integrate Cucumber and Cypress into your test suite Use TDD to drive the process of writing tests Apply your existing React knowledge for using RTL Who this book is for This book is for software engineers, quality engineers and React developers who want to learn about modern practices used for testing React components using the latest testing tool, RTL. Basic knowledge of React development is required to get the most out of this book.

React 16 Essentials

A fast-paced, hands-on guide to designing and building scalable and maintainable web apps with React 16

Author: Artemij Fedosejev

Publisher: Packt Publishing Ltd

ISBN:

Category: Computers

Page: 240

View: 367

Everything you need to start working with React 16 and assess React Fiber About This Book Hands-on examples and tutorials for the latest React 16 release Assess the impact of React Fiber for your future web development Build maintainable and high performance React 16 web applications Who This Book Is For If you're a frontend developer with some knowledge of native JavaScript development and frontend frameworks, wishing to learn the fastest web user interface library there is, then this book is ideal for you. What You Will Learn Learn to code React 16 with hands-on examples and clear tutorials Install powerful React 16 tools to make development much more efficient Understand the impact of React Fiber today and the future of your web development Utilize the Redux application architecture with your React components Create React 16 elements with properties and children Get started with stateless and stateful React components Use JSX to speed up your React 16 development process Add reactivity to your React 16 components with lifecycle methods Test your React 16 components with the Jest test framework In Detail React 16 Essentials, Second Edition, fully updated for React 16, takes you on a fast-paced journey through building your own maintainable React 16 applications. React experts Artemij Fedosejev and Adam Boduch give you all the essentials you need to know and start working with React 16, in this new edition of the best-selling React.js Essentials title. You'll find the latest React 16 code updates, assessment of React Fiber, new coverage of Redux, and how to work as a modern React developer. The authors offer you their current assessment of React Fiber, and you'll soon be exploring React 16 hands on, creating your own single and multiple user interface elements with React 16. You'll then see how to create stateless and stateful components and make them reactive. You'll also learn to interact between your components and lifecycle methods, and gauge how to effectively integrate your user interface components with other JavaScript libraries. Delve deep into the core elements of the Redux architecture and learn how to manage your application and data persistence. Then go the extra mile with the Jest test framework, and run multiple tests on your applications and find solutions to scale without complexity. Today React is used by Facebook, Instagram, Khan Academy, and Imperial College London, to name a few. Many new users recognize the benefits of React and adopt it in their own projects, forming a fast-growing community. The speed at which React has evolved promises a bright future for anyone who invests in learning it today. Let Artemij and Adam bring you a brand new look at React 16 and React Fiber, and move your web development into the future. Style and approach React 16 Essentials, Second Edition, will take you on a fast-paced, hands-on journey through building your own maintainable React 16 applications.

Mastering React Test-Driven Development

Build rock-solid, well-tested web apps with React, Redux and GraphQL

Author: Daniel Irvine

Publisher: Packt Publishing Ltd

ISBN:

Category: Computers

Page: 496

View: 377

Implement TDD for your React applications using Jest, React Router, Redux, and GraphQL/Relay. Learn BDD and end-to-end acceptance testing with CucumberJS and Puppeteer. Key Features Learn the TDD process using the React framework Build complex, real-world applications with a pragmatic approach to TDD Use Cucumber for acceptance and BDD testing, bringing TDD to the wider team Book Description Many programmers are aware of TDD but struggle to apply it beyond basic examples. This book teaches how to build complex, real-world applications using Test-Driven Development (TDD). It takes a first principles approach to the TDD process using plain Jest and includes test-driving the integration of libraries including React Router, Redux, and Relay (GraphQL). Readers will practice systematic refactoring while building out their own test framework, gaining a deep understanding of TDD tools and techniques. They will learn how to test-drive features such as client- and server-side form validation, data filtering and searching, navigation and user workflow, undo/redo, animation, LocalStorage access, WebSocket communication, and querying GraphQL endpoints. The book covers refactoring codebases to use the React Router and Redux libraries. via TDD. Redux is explored in depth, with reducers, middleware, sagas, and connected React components. The book also covers acceptance testing using Cucumber and Puppeteer. The book is fully up to date with React 16.9 and has in-depth coverage of hooks and the ‘act’ test helper. What you will learn Build test-driven applications using React 16.9+ and Jest Build complete web applications using a variety of HTML input elements Understand the different types of test double and when to apply them Test-drive the Integration of libraries such as React Router, Redux, and Relay (GraphQL) Learn when to be pragmatic and how to apply TDD shortcuts Test-drive interaction with browser APIs including fetch and WebSockets Use Cucumber.js and Puppeteer to build BDD-style acceptance tests for your applications Build and test async Redux code using redux-saga and expect-redux Who this book is for The target audience for this book is JavaScript developers who are looking to implement test-driven and behavior-driven approaches for their React applications.

Hands-On Reactive Programming with Python

Event-driven development unraveled with RxPY

Author: Romain Picard

Publisher: Packt Publishing Ltd

ISBN:

Category: Computers

Page: 420

View: 314

A comprehensive guide to help you understand the principles of Reactive and asynchronous programming and its benefits Key Features Explore the advantages of Reactive programming Use concurrency and parallelism in RxPY to build powerful reactive applications Deploy and scale your reactive applications using Docker Book Description Reactive programming is central to many concurrent systems, but it’s famous for its steep learning curve, which makes most developers feel like they're hitting a wall. With this book, you will get to grips with reactive programming by steadily exploring various concepts This hands-on guide gets you started with Reactive Programming (RP) in Python. You will learn abouta the principles and benefits of using RP, which can be leveraged to build powerful concurrent applications. As you progress through the chapters, you will be introduced to the paradigm of Functional and Reactive Programming (FaRP), observables and observers, and concurrency and parallelism. The book will then take you through the implementation of an audio transcoding server and introduce you to a library that helps in the writing of FaRP code. You will understand how to use third-party services and dynamically reconfigure an application. By the end of the book, you will also have learned how to deploy and scale your applications with Docker and Traefik and explore the significant potential behind the reactive streams concept, and you'll have got to grips with a comprehensive set of best practices. What you will learn Structure Python code for better readability, testing, and performance Explore the world of event-based programming Grasp the use of the most common operators in Rx Understand reactive extensions beyond simple examples Master the art of writing reusable components Deploy an application on a cloud platform with Docker and Traefik Who this book is for If you are a Python developer who wants to learn Reactive programming to build powerful concurrent and asynchronous applications, this book is for you. Basic understanding of the Python language is all you need to understand the concepts covered in this book.

Bulletin of the Atomic Scientists

Author:

Publisher:

ISBN:

Category:

Page: 116

View: 755

The Bulletin of the Atomic Scientists is the premier public resource on scientific and technological developments that impact global security. Founded by Manhattan Project Scientists, the Bulletin's iconic "Doomsday Clock" stimulates solutions for a safer world.

Smart Innovations in Engineering and Technology

Author: Ryszard Klempous

Publisher: Springer Nature

ISBN:

Category: Technology & Engineering

Page: 284

View: 755

This easy-to-understand book discusses applications of current technologies and the foundations for their extension into emerging areas in the future. It includes research presented at two conferences: 5th International IBM Cloud Academy Conference, 2017, held in Wrocław, Poland. 5th Asia‐Pacific Conference on Computer Assisted and System Engineering, 2017, held in Guilin, China. These conferences focused on system and application engineering, including achievements in the interdisciplinary topics of cloud computing, big data, IoT and mobile communications. Featuring 19 chapters, the book has the potential to influence current and future research and applications combining the best attributes of computing, mathematics, artificial intelligence, biometrics and software engineering to create a comprehensive research application domain.

React Quickly

Painless web apps with React, JSX, Redux, and GraphQL

Author: Azat Mardan

Publisher: Simon and Schuster

ISBN:

Category: Computers

Page: 528

View: 239

Summary React Quickly is for anyone who wants to learn React.js fast. This hands-on book teaches you the concepts you need with lots of examples, tutorials, and a large main project that gets built throughout the book. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Successful user interfaces need to be visually interesting, fast, and flowing. The React.js JavaScript library supercharges view-heavy web applications by improving data flow between UI components. React sites update visual elements efficiently and smoothly, minimizing page reloads. React is developer friendly, with a strong ecosystem to support the dev process along the full application stack. And because it's all JavaScript, React is instantly familiar. About the Book React Quickly is the tutorial for web developers who want to get started fast with React.js. Following carefully chosen and clearly explained examples, you'll learn React development using your existing JavaScript and web dev skills. You'll explore a host of different projects as you learn about web components, forms, and data. What's Inside Master React fundamentals Build full web apps with data and routing Test components Optimize React apps About the Reader This book is for developers comfortable building web applications with JavaScript. About the Author Azat Mardan is a Tech Fellow at Capital One with extensive experience using and teaching JavaScript and Node, and author of several books on JavaScript, Node, React, and Express. Table of Contens PART 1 - REACT FOUNDATION Meeting React Baby steps with React Introduction to JSX Making React interactive with states React component lifecycle events Handling events in React Working with forms in React Scaling React components Project: Menu component Project: Tooltip component Project: Timer component PART 2 - REACT ARCHITECTURE The Webpack build tool React routing Working with data using Redux Working with data using GraphQL Unit testing React with Jest React on Node and Universal JavaScript Project: Building a bookstore with React Router Project: Checking passwords with Jest Project: Implementing autocomplete with Jest, Express, and MongoDB APPENDIXES Appendix A - Installing applications used in this book Appendix B - React cheatsheet Appendix C - Express.js cheatsheet Appendix D - MongoDB and Mongoose cheatsheet Appendix E - ES6 for success

Statistics in Toxicology Using R

Author: Ludwig A. Hothorn

Publisher: CRC Press

ISBN:

Category: Mathematics

Page: 234

View: 182

The apparent contradiction between statistical significance and biological relevance has diminished the value of statistical methods as a whole in toxicology. Moreover, recommendations for statistical analysis are imprecise in most toxicological guidelines. Addressing these dilemmas, Statistics in Toxicology Using R explains the statistical analysis of selected experimental data in toxicology and presents assay-specific suggestions, such as for the in vitro micronucleus assay. Mostly focusing on hypothesis testing, the book covers standardized bioassays for chemicals, drugs, and environmental pollutants. It is organized according to selected toxicological assays, including: Short-term repeated toxicity studies Long-term carcinogenicity assays Studies on reproductive toxicity Mutagenicity assays Toxicokinetic studies The book also discusses proof of safety (particularly in ecotoxicological assays), toxicogenomics, the analysis of interlaboratory studies and the modeling of dose-response relationships for risk assessment. For each toxicological problem, the author describes the statistics involved, matching data example, R code, and outcomes and their interpretation. This approach allows you to select a certain bioassay, identify the specific data structure, run the R code with the data example, understand the test outcome and interpretation, and replace the data set with your own data and run again.

Android Development with Kotlin

Author: Marcin Moskala

Publisher: Packt Publishing Ltd

ISBN:

Category: Computers

Page: 440

View: 959

Learn how to make Android development much faster using a variety of Kotlin features, from basics to advanced, to write better quality code. About This Book Leverage specific features of Kotlin to ease Android application development Write code based on both object oriented and functional programming to build robust applications Filled with various practical examples so you can easily apply your knowledge to real world scenarios Identify the improved way of dealing with common Java patterns Who This Book Is For This book is for developers who have a basic understanding of Java language and have 6-12 months of experience with Android development and developers who feel comfortable with OOP concepts. What You Will Learn Run a Kotlin application and understand the integration with Android Studio Incorporate Kotlin into new/existing Android Java based project Learn about Kotlin type system to deal with null safety and immutability Define various types of classes and deal with properties Define collections and transform them in functional way Define extensions, new behaviours to existing libraries and Android framework classes Use generic type variance modifiers to define subtyping relationship between generic types Build a sample application In Detail Nowadays, improved application development does not just mean building better performing applications. It has become crucial to find improved ways of writing code. Kotlin is a language that helps developers build amazing Android applications easily and effectively. This book discusses Kotlin features in context of Android development. It demonstrates how common examples that are typical for Android development, can be simplified using Kotlin. It also shows all the benefits, improvements and new possibilities provided by this language. The book is divided in three modules that show the power of Kotlin and teach you how to use it properly. Each module present features in different levels of advancement. The first module covers Kotlin basics. This module will lay a firm foundation for the rest of the chapters so you are able to read and understand most of the Kotlin code. The next module dives deeper into the building blocks of Kotlin, such as functions, classes, and function types. You will learn how Kotlin brings many improvements to the table by improving common Java concepts and decreasing code verbosity. The last module presents features that are not present in Java. You will learn how certain tasks can be achieved in simpler ways thanks to Kotlin. Through the book, you will learn how to use Kotlin for Android development. You will get to know and understand most important Kotlin features, and how they can be used. You will be ready to start your own adventure with Android development with Kotlin.

Proceedings

Author:

Publisher:

ISBN:

Category: Computer storage devices

Page:

View: 418

Beginning React

Simplify your frontend development workflow and enhance the user experience of your applications with React

Author: Andrea Chiarelli

Publisher: Packt Publishing Ltd

ISBN:

Category: Computers

Page: 96

View: 787

Take your web applications to a whole new level with efficient, component-based UIs that deliver cutting-edge interactivity and performance. Key Features Elaborately explains basics before introducing advanced topics Explains creating and managing the state of components across applications Implement over 15 practical activities and exercises across 11 topics to reinforce your learning Book Description Projects like Angular and React are rapidly changing how development teams build and deploy web applications to production. In this book, you’ll learn the basics you need to get up and running with React and tackle real-world projects and challenges. It includes helpful guidance on how to consider key user requirements within the development process, and also shows you how to work with advanced concepts such as state management, data-binding, routing, and the popular component markup that is JSX. As you complete the included examples, you’ll find yourself well-equipped to move onto a real-world personal or professional frontend project. What you will learn Understand how React works within a wider application stack Analyze how you can break down a standard interface into specific components Successfully create your own increasingly complex React components with HTML or JSX Correctly handle multiple user events and their impact on overall application state Understand the component lifecycle to optimize the UX of your application Configure routing to allow effortless, intuitive navigation through your components Who this book is for If you are a frontend developer who wants to create truly reactive user interfaces in JavaScript, then this is the book for you. For React, you’ll need a solid foundation in the essentials of the JavaScript language, including new OOP features that were introduced in ES2015. An understanding of HTML and CSS is assumed, and a basic knowledge of Node.js will be useful in the context of managing a development workflow, but is not essential.

Quick Start Full Stack Web Development

Build Secure Asynchronous Single-Page Apps with Flask, React, and PostgreSQL

Author: Erik M. Ferragut

Publisher: Socratecha

ISBN:

Category: Computers

Page: 354

View: 591

Quick Start Full Stack Web Development removes the trial and error from learning to make web applications. Being a full stack web developer does not mean knowing everything about every web technology,but rather knowing enough to build a complete application including a front end, a back end, and a database. Web searching can provide useful snippets of information, but integrating those pieces into a working whole remains a challenge. This book will walk the reader through both the component technologies and the steps required to get the pieces to work together. This clear focus can save countless hours of frustration compared to trying to assemble a working solution from inconsistent and outdated sources. The reader should have some familiarity with Python or JavaScript, but no web programming experience is assumed. Quick Start Full Stack Web Development explains key concepts, such as REST APIs and JSON Web Tokens, and then puts these concepts into practice with real, working examples. The examples are built step-by-step, providing an opportunity to experiment with the ideas. Furthermore, there is a consistent focus on getting instant feedback as changes are made to the code, a good practice for quickly building intuition and gaining experience. The chosen technologies (React, Flask, and PostgreSQL) are excellent options for newcomers to web development because they are relatively easy to learn, have vibrant supportive communities, and can scale to large and complex applications. Rather than providing a cursory introduction to a variety of technology options, Quick Start Full Stack Web Development provides a thorough foundation in one technology stack. This prevents confusion, provides more opportunities to reinforce concepts, and leads more quickly to significant results. Learn how to: * Build a Python Flask REST API * Develop and style a React client * Design SQLite and PostgreSQL databases using SQLAlchemy * Incorporate JSON Web Tokens (JWT) for authentication * Test it using httpie, browser dev tools, pytest, and Jest * Document it using Sphinx and Storybook * Deploy using Gunicorn and NGINX on a Platform-as-a-Service The result is a fully functional full stack web application that addresses all the little details, like serving the client and API from the same server, managing the environment with a config file, making the documentation visible in the git repository, and populating and uploading databases. Because it focuses on getting to a working application, Quick Start Full Stack Web Development is well suited to entrepreneurs and solopreneurs building out their minimal viable products. And because it explains the concepts and shows them in practice, it will help programmers who want to get into web development. If you want to learn these powerful skills as quickly as possible, then this book is for you.

Environmental Science

Author: Michael L. McKinney

Publisher: Jones & Bartlett Learning

ISBN:

Category: BUSINESS & ECONOMICS

Page: 576

View: 583

Environmental Science: Systems and Solutions, Sixth Edition features updated data and additional tables with statistics throughout to lay the groundwork for a fair and apolitical foundational understanding of environmental science. Important Notice: The digital edition of this book is missing some of the images or content found in the physical edition.

Oceanographic Analysis with R

Author: Dan E. Kelley

Publisher: Springer

ISBN:

Category: Medical

Page: 290

View: 826

This book presents the R software environment as a key tool for oceanographic computations and provides a rationale for using R over the more widely-used tools of the field such as MATLAB. Kelley provides a general introduction to R before introducing the ‘oce’ package. This package greatly simplifies oceanographic analysis by handling the details of discipline-specific file formats, calculations, and plots. Designed for real-world application and developed with open-source protocols, oce supports a broad range of practical work. Generic functions take care of general operations such as subsetting and plotting data, while specialized functions address more specific tasks such as tidal decomposition, hydrographic analysis, and ADCP coordinate transformation. In addition, the package makes it easy to document work, because its functions automatically update processing logs stored within its data objects. Kelley teaches key R functions using classic examples from the history of oceanography, specifically the work of Alfred Redfield, Gordon Riley, J. Tuzo Wilson, and Walter Munk. Acknowledging the pervasive popularity of MATLAB, the book provides advice to users who would like to switch to R. Including a suite of real-life applications and over 100 exercises and solutions, the treatment is ideal for oceanographers, technicians, and students who want to add R to their list of tools for oceanographic analysis.

CERN.

Author:

Publisher:

ISBN:

Category: Nuclear physics

Page:

View: 478

Hands-On Design Patterns with React Native

Proven techniques and patterns for efficient native mobile development with JavaScript

Author: Mateusz Grzesiukiewicz

Publisher: Packt Publishing Ltd

ISBN:

Category: Computers

Page: 302

View: 482

Learn how to write cross platform React Native code by using effective design patterns in the JavaScript world. Get to know industry standard patterns as well as situational patterns. Decouple your application with these set of “Idea patterns”. Key Features Mobile development in React Native should be done in a reusable way. Learn how to build scalable applications using JavaScript patterns that are battle tested. Try effective techniques on your own using over 80 standalone examples. Book Description React Native helps developers reuse code across different mobile platforms like iOS and Android. This book will show you effective design patterns in the React Native world and will make you ready for professional development in big teams. The book will focus only on the patterns that are relevant to JavaScript, ECMAScript, React and React Native. However, you can successfully transfer a lot of the skills and techniques to other languages. I call them “Idea patterns”. This book will start with the most standard development patterns in React like component building patterns, styling patterns in React Native and then extend these patterns to your mobile application using real world practical examples. Each chapter comes with full, separate source code of applications that you can build and run on your phone. The book is also diving into architectural patterns. Especially how to adapt MVC to React environment. You will learn Flux architecture and how Redux is implementing it. Each approach will be presented with its pros and cons. You will learn how to work with external data sources using libraries like Redux thunk and Redux Saga. The end goal is the ability to recognize the best solution for a given problem for your next mobile application. What you will learn Explore the design Patterns in React Native Learn the best practices for React Native development Explore common React patterns that are highly used within React Native development Learn to decouple components and use dependency injection in your applications Explore the best ways of fetching data from the backend systems Learn the styling patterns and how to implement custom mobile designs Explore the best ways to organize your application code in big codebases Who this book is for The ideal target audience for this book are people eager to learn React Native design patterns who already know the basics of JavaScript. We can assume that the target audience already knows how to write Hello World in JavaScript and know what are the functions, recursive functions, JavaScript types and loops.

Readings in Qualitative Reasoning About Physical Systems

Author: Daniel S. Weld

Publisher: Morgan Kaufmann

ISBN:

Category: Science

Page: 732

View: 689

Readings in Qualitative Reasoning about Physical Systems describes the automated reasoning about the physical world using qualitative representations. This text is divided into nine chapters, each focusing on some aspect of qualitative physics. The first chapter deal with qualitative physics, which is concerned with representing and reasoning about the physical world. The goal of qualitative physics is to capture both the commonsense knowledge of the person on the street and the tacit knowledge underlying the quantitative knowledge used by engineers and scientists. The succeeding chapter discusses the qualitative calculus and its role in constructing an envisionment that includes behavior over both mythical time and elapsed time. These topics are followed by reviews of the mathematical aspects of qualitative reasoning, history-based simulation and temporal reasoning, as well as the intelligence in scientific computing. The final chapters are devoted to automated modeling for qualitative reasoning and causal explanations of behavior. These chapters also examine the qualitative kinematics of reasoning about shape and space. This book will prove useful to psychologists and psychiatrists.

Practical Digital Design Using ICs

Author: Joseph D. Greenfield

Publisher: Prentice Hall

ISBN:

Category: Technology & Engineering

Page: 720

View: 136

New third edition offers a start-to- finish approach to digital circuit design, beginning with simple circuits and advancing to highly complex circuits. Coverage runs from simple circuits easily constructed in the laboratory through complex circuits such as those used in memory systems, computers, and computer interfacing, including many examples of analysis and design. A solid introductory guide for electrical/electronics technicians and hobbyists.