Rupert 'fildon' McKay's Blog

Rupert 'fildon' McKay's Blog

ESLint vs Prettier

Oct 9, 20214 min read 851 views

Photo by Nagesh Badu on Unsplash TL;DR: ESLint should identify semantic errors which require programmer intervention to fix, while prettier should identify text formatting errors which do not require programmer intervention to fix. The problem with S...

ESLint vs Prettier

TypeScript 4.4 > useUnknownInCatchVariables

Aug 30, 20214 min read 339 views

Photo by Ray Hennessy on Unsplash Key takeaways: The unknown type allows nothing. The any type allows everything JavaScript allows throwing any expression useUnknownInCatchVariables treats caught errors as unknown Last week I updated our main repo...

TypeScript 4.4 > useUnknownInCatchVariables

Publishing TypeScript React components to NPM

Jul 17, 20217 min read 169 views

Photo by Jess Bailey on Unsplash Publishing a TypeScript React component library to NPM Key takeaways: compile to a dist directory copy package.json and README.md files to the dist directory publish the dist directory If you get stuck or lost at a...

Publishing TypeScript React components to NPM

Handling optional values in TypeScript

Jul 10, 20214 min read 124 views

Photo by Emily Morter on Unsplash Key takeaways: Prefer ?? to || Prefer foo?.bar to foo && foo.bar In this post, we'll dive into three separate but similar syntaxes related to values that might not be defined: Optional Properties (?:) Nullish Coa...

Handling optional values in TypeScript

Mocking in Jest with TypeScript and React

Jul 3, 202111 min read 447 views

Photo by Andre Mouton on Unsplash Key takeaways: jest.mock covers many use cases jest.MockedFunction<typeof YourFunction> is the best for type-safe mock functions Don't be afraid to mock React components they are just functions! Getting started wi...

Mocking in Jest with TypeScript and React

Seeing through JSX to understand React component Types

Jun 27, 20217 min read 2.1K views

Photo by Michael Dziedzic on Unsplash Here are the big takes right away: Don't use React.FC. Explicitly type your props including permitted children types. Prefer inferred return types, but JSX.Element if you have to. To justify these claims, we w...

Seeing through JSX to understand React component Types