add five ts medium challenges

Author: diaz-rodrigo

Languages/Typescript/Generics/02693-medium-endswith.ts

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+/*
+  2693 - EndsWith
+  -------
+  by jiangshan (@jiangshanmeta) #medium #template-literal
+
+  ### Question
+
+  Implement `EndsWith<T, U>` which takes two exact string types and returns whether `T` ends with `U`
+
+  For example:
+
+  ```typescript
+  type a = EndsWith<'abc', 'bc'> // expected to be true
+  type b = EndsWith<'abc', 'abc'> // expected to be true
+  type c = EndsWith<'abc', 'd'> // expected to be false
+  ```
+
+  > View on GitHub: https://tsch.js.org/2693
+*/
+
+/* _____________ Your Code Here _____________ */
+
+type EndsWith<T extends string, U extends string> = T extends `${infer _}${U}`
+  ? true
+  : false;
+
+/* _____________ Test Cases _____________ */
+import type { Equal, Expect } from "@type-challenges/utils";
+
+type cases = [
+  Expect<Equal<EndsWith<"abc", "bc">, true>>,
+  Expect<Equal<EndsWith<"abc", "abc">, true>>,
+  Expect<Equal<EndsWith<"abc", "d">, false>>,
+  Expect<Equal<EndsWith<"abc", "ac">, false>>,
+  Expect<Equal<EndsWith<"abc", "">, true>>,
+  Expect<Equal<EndsWith<"abc", " ">, false>>
+];
+
+/* _____________ Further Steps _____________ */
+/*
+  > Share your solutions: https://tsch.js.org/2693/answer
+  > View solutions: https://tsch.js.org/2693/solutions
+  > More Challenges: https://tsch.js.org
+*/

Languages/Typescript/Generics/02759-medium-requiredbykeys.ts

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+/*
+  2759 - RequiredByKeys
+  -------
+  by jiangshan (@jiangshanmeta) #medium #object
+
+  ### Question
+
+  Implement a generic `RequiredByKeys<T,  K>` which takes two type argument `T` and `K`.
+
+  `K` specify the set of properties of `T` that should set to be required. When `K` is not provided, it should make all properties required just like the normal `Required<T>`.
+
+  For example
+
+  ```typescript
+  interface User {
+    name?: string
+    age?: number
+    address?: string
+  }
+
+  type UserRequiredName = RequiredByKeys<User, 'name'> // { name: string; age?: number; address?: string }
+
+  ```
+
+  > View on GitHub: https://tsch.js.org/2759
+*/
+
+/* _____________ Your Code Here _____________ */
+
+type RequiredByKeys<T, K extends keyof T = any> = Required<
+  {
+    [P in keyof T as P extends K ? P : never]: T[P];
+  }
+> &
+  {
+    [P in keyof T as P extends K ? never : P]: T[P];
+  } extends infer M
+  ? {
+      [P in keyof M]: M[P];
+    }
+  : Required<T>;
+
+/* _____________ Test Cases _____________ */
+import type { Equal, Expect } from "@type-challenges/utils";
+
+interface User {
+  name?: string;
+  age?: number;
+  address?: string;
+}
+
+interface UserRequiredName {
+  name: string;
+  age?: number;
+  address?: string;
+}
+
+interface UserRequiredNameAndAge {
+  name: string;
+  age: number;
+  address?: string;
+}
+
+type cases = [
+  Expect<Equal<RequiredByKeys<User, "name">, UserRequiredName>>,
+  Expect<Equal<RequiredByKeys<User, "name" | "age">, UserRequiredNameAndAge>>,
+  Expect<Equal<RequiredByKeys<User>, Required<User>>>,
+  // @ts-expect-error
+  Expect<Equal<RequiredByKeys<User, "name" | "unknown">, UserRequiredName>>
+];
+
+/* _____________ Further Steps _____________ */
+/*
+  > Share your solutions: https://tsch.js.org/2759/answer
+  > View solutions: https://tsch.js.org/2759/solutions
+  > More Challenges: https://tsch.js.org
+*/

Languages/Typescript/Generics/02793-medium-mutable.ts

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+/*
+  2793 - Mutable
+  -------
+  by jiangshan (@jiangshanmeta) #medium #readonly #object-keys
+
+  ### Question
+
+  Implement the generic ```Mutable<T>``` which makes all properties in ```T``` mutable (not readonly).
+
+  For example
+
+  ```typescript
+  interface Todo {
+    readonly title: string
+    readonly description: string
+    readonly completed: boolean
+  }
+
+  type MutableTodo = Mutable<Todo> // { title: string; description: string; completed: boolean; }
+
+  ```
+
+  > View on GitHub: https://tsch.js.org/2793
+*/
+
+/* _____________ Your Code Here _____________ */
+
+type Mutable<T extends { [key: string]: any }> = {
+  -readonly [K in keyof T]: T[K];
+};
+
+/* _____________ Test Cases _____________ */
+import type { Equal, Expect } from "@type-challenges/utils";
+
+interface Todo1 {
+  title: string;
+  description: string;
+  completed: boolean;
+  meta: {
+    author: string;
+  };
+}
+
+type List = [1, 2, 3];
+
+type cases = [
+  Expect<Equal<Mutable<Readonly<Todo1>>, Todo1>>,
+  Expect<Equal<Mutable<Readonly<List>>, List>>
+];
+
+type errors = [
+  // @ts-expect-error
+  Mutable<"string">,
+  // @ts-expect-error
+  Mutable<0>
+];
+
+/* _____________ Further Steps _____________ */
+/*
+  > Share your solutions: https://tsch.js.org/2793/answer
+  > View solutions: https://tsch.js.org/2793/solutions
+  > More Challenges: https://tsch.js.org
+*/

Languages/Typescript/Generics/02852-medium-omitbytype.ts

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+/*
+  2852 - OmitByType
+  -------
+  by jiangshan (@jiangshanmeta) #medium #object
+
+  ### Question
+
+  From ```T```, pick a set of properties whose type are not assignable to ```U```.
+
+  For Example
+
+  ```typescript
+  type OmitBoolean = OmitByType<{
+    name: string
+    count: number
+    isReadonly: boolean
+    isEnable: boolean
+  }, boolean> // { name: string; count: number }
+  ```
+
+  > View on GitHub: https://tsch.js.org/2852
+*/
+
+/* _____________ Your Code Here _____________ */
+
+type OmitByType<T extends { [key: string]: any }, U> = {
+  [K in keyof T as T[K] extends U ? never : K]: T[K];
+};
+
+/* _____________ Test Cases _____________ */
+import type { Equal, Expect } from "@type-challenges/utils";
+
+interface Model {
+  name: string;
+  count: number;
+  isReadonly: boolean;
+  isEnable: boolean;
+}
+
+type cases = [
+  Expect<Equal<OmitByType<Model, boolean>, { name: string; count: number }>>,
+  Expect<
+    Equal<
+      OmitByType<Model, string>,
+      { count: number; isReadonly: boolean; isEnable: boolean }
+    >
+  >,
+  Expect<
+    Equal<
+      OmitByType<Model, number>,
+      { name: string; isReadonly: boolean; isEnable: boolean }
+    >
+  >
+];
+
+/* _____________ Further Steps _____________ */
+/*
+  > Share your solutions: https://tsch.js.org/2852/answer
+  > View solutions: https://tsch.js.org/2852/solutions
+  > More Challenges: https://tsch.js.org
+*/

Languages/Typescript/Generics/03062-medium-shift.ts

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+/*
+  3062 - Shift
+  -------
+  by jiangshan (@jiangshanmeta) #medium #array
+
+  ### Question
+
+  Implement the type version of ```Array.shift```
+
+  For example
+
+  ```typescript
+  type Result = Shift<[3, 2, 1]> // [2, 1]
+  ```
+
+  > View on GitHub: https://tsch.js.org/3062
+*/
+
+/* _____________ Your Code Here _____________ */
+
+type Shift<T extends any[]> = T extends [infer _, ...infer Rest] ? Rest : [];
+
+/* _____________ Test Cases _____________ */
+import type { Equal, Expect } from "@type-challenges/utils";
+
+type cases = [
+  // @ts-expect-error
+  Shift<unknown>,
+  Expect<Equal<Shift<[]>, []>>,
+  Expect<Equal<Shift<[1]>, []>>,
+  Expect<Equal<Shift<[3, 2, 1]>, [2, 1]>>,
+  Expect<Equal<Shift<["a", "b", "c", "d"]>, ["b", "c", "d"]>>
+];
+
+/* _____________ Further Steps _____________ */
+/*
+  > Share your solutions: https://tsch.js.org/3062/answer
+  > View solutions: https://tsch.js.org/3062/solutions
+  > More Challenges: https://tsch.js.org
+*/