Zhentiw - 博客园

2022年10月18日

摘要： Must have Configure Jest to Run Setup for All Tests with Jest setupFilesAfterEnv We want to include '@testing-library/jest-dom'so that we can have suc 阅读全文

posted @ 2022-10-18 13:59 Zhentiw 阅读(41) 评论(0) 推荐(0)

[Typescript] Tips: Ensure that all call sites must be given value

摘要： This one little tip has saved me hours of refactoring time. Passing string | undefined instead of ?: string ensures that ALL call sites must be given 阅读全文

posted @ 2022-10-18 01:39 Zhentiw 阅读(31) 评论(0) 推荐(0)

[Typescript] Tips: Make accessing objects safer by enabling 'noUncheckedIndexedAccess' in tsconfig

摘要： The "noUncheckedIndexedAccess" is the most awesome config option you've never heard of. It makes accessing objects a lot safer, and also powers up Typ 阅读全文

posted @ 2022-10-18 01:33 Zhentiw 阅读(37) 评论(0) 推荐(0)

[Typescript] Tips: Map over a union type

摘要： Mapping over a union type can feel tricky to conceptualise. But actually, TypeScript does it all for you - using Distributive Conditional Types. Here, 阅读全文

posted @ 2022-10-18 01:22 Zhentiw 阅读(41) 评论(0) 推荐(0)

[Typescript] Tips: Use 'declare global' to allow types to cross module boundaries

摘要： Globals in TypeScript?! 🤯 declare global is a super useful tool for when you want to allow types to cross module boundaries. Here, we create a Global 阅读全文

posted @ 2022-10-18 01:18 Zhentiw 阅读(153) 评论(0) 推荐(0)

2022年10月17日

[Typescript] 54. Medium - Tuple to Nested Object

摘要： Given a tuple type T that only contains string type, and a type U, build an object recursively. type a = TupleToNestedObject<['a'], string> // {a: str 阅读全文

posted @ 2022-10-17 14:53 Zhentiw 阅读(31) 评论(0) 推荐(0)

[Typescript] 53. Medium - Shift

摘要： Implement the type version of Array.shift For example type Result = Shift<[3, 2, 1]> // [2, 1] /* _____________ Your Code Here _____________ */ type S 阅读全文

posted @ 2022-10-17 14:41 Zhentiw 阅读(31) 评论(0) 推荐(0)

[Unit testing RxJS] Testing Observables with Subscribe and assert Parttern

摘要： const { of } = require("rxjs"); const { mergeMap, map, delay, catchError } = require("rxjs/operators"); describe("subscribe & assert testing in RxJS", 阅读全文

posted @ 2022-10-17 14:12 Zhentiw 阅读(40) 评论(0) 推荐(0)

2022年10月16日

[Typescript] 52. Medium - ObjectEntries

摘要： Implement the type version of Object.entries For example interface Model { name: string; age: number; locations: string[] | null; } type modelEntries 阅读全文

posted @ 2022-10-16 17:08 Zhentiw 阅读(31) 评论(0) 推荐(0)

2022年10月15日

[Typescript] 51. Medium - Mutable

摘要： Implement the generic Mutable<T> which makes all properties in T mutable (not readonly). For example interface Todo { readonly title: string readonly 阅读全文

posted @ 2022-10-15 20:36 Zhentiw 阅读(32) 评论(0) 推荐(0)

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