Published inDev Genius·PinnedMastering TypeScript Decorators: A Comprehensive Guide to Enhancing Your CodeWhy do we need a decorator? If you’re new to TypeScript decorators, you may be wondering why they’re necessary. Before we delve into the answer, let’s take a look at a small code snippet. The getHomeAddress function violates the single responsibility principle because it performs multiple tasks that should be handled by separate functions. Specifically, the…Typescript With React9 min readTypescript With React9 min read
Published inDev Genius·PinnedLearn rxjs in an easy wayUnlike Object-oriented programming (where states and behaviors are coupled together into an object), Reactive programming is a different programming mindset. It focuses on reacting to changes in a pure-function way. If you have ever used excel you already know what reactive means. …Rxjs9 min readRxjs9 min read
Published inDev Genius·PinnedA quick guide about Dependency Injection (in Angular/React)In fact, DI (Dependency Injection) is a super simple concept that is widely used in software development. It basically means that when a component needs some props to render, those props are passed from the outside of this component instead of creating these props directly inside of this component. These…React4 min readReact4 min read
Published inJavaScript in Plain English·May 11, 2022The Difference Between jest.spyOn and jest.mockWhen I first started to write unit tests for react applications, I found that it is confusing whether I should use jest.spyOn or jest.mock. The golden rule is that: jest.mock is used to mock a JavaScript module. 2. jest.spyOn is used to mock what we imported from that module. …Jest2 min readJest2 min read
Sep 12, 2021Some thoughts about unit test in ReactDo not wrap fireEvent in “act” or “await waitFor” If we are testing with fireEvent in react-testing library but found this error in the console Warning: An update to Example inside a test was not wrapped in act(...) It means that we did not wait for react to flush the…React4 min readReact4 min read
Aug 21, 2021Learn Git in a scenario-based wayThe git commands you will learn: git stash git reset git cherry-pick git blame git reflog git rebase These are all very important and easy-to-understand git commands in daily dev workflow. git stash 1. I am currently in ticket001 branch adding a new feature. I just finished 50% of the work but I have not committed anything. I am assigned an emergent bug fix ticket. I need to do the bug fix ticket right now. What should I do with my uncommited work?Git5 min readGit5 min read
Aug 13, 2019Things You Need to Know About TypeScriptThis passage is not finished and is still in progress… Numbers: const bigNumber:number=1_100_200_3000 //much easier to read; what this compiles to javascript is const bigNumber=11002003000; In typescript, using underscore makes your code easier to read. 2. Add “!” to tell ts to ignore it 3. keyof interface IPet{ name:string…Typescript2 min readTypescript2 min read
