Typescript isn’t able to infer the right type of the return type

array.sort((x, y) => +new Date(x.createdAt) - +new Date(y.createdAt));

// Get path to resource on disk
 const onDiskPath = vscode.Uri.file( 
   path.join(context.extensionPath, 'css', 'style.css')
);
// And get the special URI to use with the webview
const cssURI = panel.webview.asWebviewUri(onDiskPath);

const sessionMiddleware = expressSession({
    secret: 'Tecky Academy teaches typescript',
    resave:true,
    saveUninitialized:true,
    cookie:{secure:false}
});

app.use(sessionMiddleware);

io.use((socket,next)=>{
    let req = socket.request as express.Request
    let res = req.res as express.Response
    sessionMiddleware(req, res, next as express.NextFunction
});
//...
io.on('connection', function (socket) {
    // You can set any values you want to session here.
    const req = socket.request as express.Request;
    req.session['key'] = 'XXX';
    // There is no auto save for session.
    socket.request.session.save();

    // You can also send data using socket.emit() although it is not very useful
    socket.emit('any-key','values');
    socket.on("disconnect",()=>{
        //... rest of the code
    })
});

const range = (from, to, step) =>
  [...Array(Math.floor((to - from) / step) + 1)].map((_, i) => from + i * step);

range(0, 9, 2);
//=> [0, 2, 4, 6, 8]

// can also assign range function as static method in Array class (but not recommended )
Array.range = (from, to, step) =>
  [...Array(Math.floor((to - from) / step) + 1)].map((_, i) => from + i * step);

Array.range(2, 10, 2);
//=> [2, 4, 6, 8, 10]

Array.range(0, 10, 1);
//=> [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Array.range(2, 10, -1);
//=> []

Array.range(3, 0, -1);
//=> [3, 2, 1, 0]

...

<ion-content class="scanner-hide" *ngIf="scanStatus == false">
  <div class="padding-container center">
    <ion-button color="primary" (click)="scanCode()"><ion-icon slot="start" name="qr-code-outline"></ion-icon> Scanear Código</ion-button> <!-- Botão que chama a função do scanner-->
  </div>
  <ion-card>
    <ion-card-content><h1>{{ result }}</h1></ion-card-content> <!-- mostra o resultado do scan -->
  </ion-card>
  
  <div class="scanner-ui"> <!-- Quando estamos a scanear, chama esta classe-->
    ...Scanner Interface
    </div>
    <div class="ad-spot"></div>
</ion-content>

function Test(): void {
 console.log('test')
 }

const a = [
    {
        k: 1, me: false, prim: false
    }, {
        k: 2, me: false, prim: false
    }, {
        k: 3, me: false, prim: false
    }, {
        k: 4, me: false, prim: false
    }, {
        k: 5, me: true, prim: true
    }, {
        k: 6, me: false, prim: false
    }
]

a
    .sort((x, y) => (x.prim === y.prim) ? 0 : x.prim ? -1 : 1)
    .sort((x, y) => (x.me === y.me) ? 0 : x.me ? -1 : 1)

console.log(a)

  it.only('Only a Care Team member can view a "Patient Profile".', () => {
    const proUser = users.proUser();
    const confirmedPatient = users.patient();
    userBasePage.createProfessional(proUser, process.env.COUNTRYAPI);
    const patient = userBasePage.createPatient(
      process.env.LANGUAGE,
      false,
      confirmedPatient,
      process.env.COUNTRYAPI,
    );
    const practiseData = fixtureHelper.getFixture('practices').sharedPractice();
    const practice = userBasePage.createSharedPractice(proUser, practiseData);
    userBasePage.addPracticeToPatient(patient, practice.practiceId);
    const proUserTemplateList = userBasePage.createProUsers(
      4,
      proUser,
      practice.id,
    );

    CountryOfResidencePage.open().submitForm(
      process.env.COUNTRY,
      process.env.LANGUAGE,
    );
    IndexPage.login(proUser.email, proUser.password)
      .goToPatientsDashboard()
      .closeFirstUseModal();
    PatientDashboardPage.openUserProfile(patient.firstName);
    PatientProfilePage.closeFirstUseModal().clickOnProfileNavButton();
    NavigationBar.clickMainHeaderHamburgerButton();
    MenuBarFrame.clickMenuSignOutLink();
    IndexPage.login(
      proUserTemplateList[0].email,
      proUserTemplateList[0].password,
      proUserTemplateList[0],
      true,
    )
      .goToPatientsDashboard()
      .closeFirstUseModal();
    PatientDashboardPage.openUserProfile(patient.firstName);
    PatientProfilePage.closeFirstUseModal().clickOnProfileNavButton();
    NavigationBar.clickMainHeaderHamburgerButton();
    MenuBarFrame.clickMenuSignOutLink();
    IndexPage.login(
      proUserTemplateList[1].email,
      proUserTemplateList[1].password,
      proUserTemplateList[1],
      true,
    )
      .goToPatientsDashboard()
      .closeFirstUseModal();
    PatientDashboardPage.openUserProfile(patient.firstName);
    PatientProfilePage.closeFirstUseModal().clickOnProfileNavButton();
    NavigationBar.clickMainHeaderHamburgerButton();
    MenuBarFrame.clickMenuSignOutLink();
    IndexPage.login(
      proUserTemplateList[2].email,
      proUserTemplateList[2].password,
      proUserTemplateList[2],
      true,
    )
      .goToPatientsDashboard()
      .closeFirstUseModal();
    PatientDashboardPage.openUserProfile(patient.firstName);
    PatientProfilePage.closeFirstUseModal().clickOnProfileNavButton();
    NavigationBar.clickMainHeaderHamburgerButton();
    MenuBarFrame.clickMenuSignOutLink();
    IndexPage.login(
      proUserTemplateList[3].email,
      proUserTemplateList[3].password,
      proUserTemplateList[3],
      true,
    )
      .goToPatientsDashboard()
      .closeFirstUseModal();
    PatientDashboardPage.openUserProfile(patient.firstName);
    PatientProfilePage.closeFirstUseModal().clickOnProfileNavButton();
  });

import { IOrdersRepository, OrderRepository } from './../repositories/OrderRepository';
import * as Knex  from 'knex';
import { IProductsRepository, ProductsRepository } from './../repositories/ProductsRepository';
import { IUserRepository, UserRepository } from './../repositories/UserRepository';

export interface IUnitOfWork {
    commit(): void;
    rollback(): void
}

// Requires a transaction scope injected on a per-request basis.
export class UnitOfWork implements IUnitOfWork {
    private context: Knex.Transaction;

    public readonly usersRepository: IUserRepository;
    public readonly ordersRepository: IOrdersRepository;
    public readonly productsRepository: IProductsRepository;

    public constructor(transactionContext: Knex.Transaction) {
        this.context = transactionContext;

        this.usersRepository = new UserRepository(transactionContext);
        this.ordersRepository = new OrderRepository(transactionContext);
        this.productsRepository = new ProductsRepository(transactionContext);
    }

    public commit(): void {
        this.context.commit();
    }

    public rollback(): void {
        this.context.rollback();
    }
}

interface IIsObject {
  (item: any): boolean;
}

interface IObject {
  [key: string]: any;
}

interface IDeepMerge {
  (target: IObject, ...sources: Array<IObject>): IObject;
}

/**
 * @description Method to check if an item is an object. Date and Function are considered
 * an object, so if you need to exclude those, please update the method accordingly.
 * @param item - The item that needs to be checked
 * @return {Boolean} Whether or not @item is an object
 */
export const isObject: IIsObject = (item: any): boolean => {
  return (item === Object(item) && !Array.isArray(item));
};

/**
 * @description Method to perform a deep merge of objects
 * @param {Object} target - The targeted object that needs to be merged with the supplied @sources
 * @param {Array<Object>} sources - The source(s) that will be used to update the @target object
 * @return {Object} The final merged object
 */
export const deepMerge: IDeepMerge = (target: IObject, ...sources: Array<IObject>): IObject => {
  // return the target if no sources passed
  if (!sources.length) {
    return target;
  }

  const result: IObject = target;

  if (isObject(result)) {
    const len: number = sources.length;

    for (let i = 0; i < len; i += 1) {
      const elm: any = sources[i];

      if (isObject(elm)) {
        for (const key in elm) {
          if (elm.hasOwnProperty(key)) {
            if (isObject(elm[key])) {
              if (!result[key] || !isObject(result[key])) {
                result[key] = {};
              }
              deepMerge(result[key], elm[key]);
            } else {
              if (Array.isArray(result[key]) && Array.isArray(elm[key])) {
                // concatenate the two arrays and remove any duplicate primitive values
                result[key] = Array.from(new Set(result[key].concat(elm[key])));
              } else {
                result[key] = elm[key];
              }
            }
          }
        }
      }
    }
  }

  return result;
};

import { User } from './User'
import { Company } from './Company'

// Instructions to every other class on how they can be an argument to 'addMarker'
// Interface acts as a gatekeeper for props. Does the prop qualify? If so, it can be an argument to the function
interface Mappable {
  location: {
    lat: number;
    lng: number;
  }
}

export class CustomMap {
  private googleMap: google.maps.Map;
  
  constructor(divId: string) {
    this.googleMap = new google.maps.Map(document.getElementById(divId), {
      zoom: 1,
      center: {
        lat: 0,
        lng: 0
      }
    })
  }

  // TS will compare User and Company types and only allow mutual props to be referenced in this function
  addMarker(mappable: Mappable): void {
    // typing 'mappable.' will use intellisense to show props that can be mapped here
    new google.maps.Marker({
      map: this.googleMap,
      position: {
        lat: mappable.location.lat,
        lng: mappable.location.lng
      }
    })
  }

}


// Company and User will be included below for reference
// Company.ts

import faker from 'faker'

export class Company {
  companyName: string;
  catchPhrase: string;
  location: {
    lat: number;
    lng: number;
  }

  constructor() {
    this.companyName = faker.company.companyName()
    this.catchPhrase = faker.company.catchPhrase()
    this.location = {
      lat: parseFloat(faker.address.latitude()),
      lng: parseFloat(faker.address.longitude())
    }

  }
}



// User.ts
import faker from 'faker'

// 'export' will export specific variables - imports will be done in curly braces
// 'export default' should nearly never be used in TypeScript - importing default exports won't use curly braces

export class User {
  name: string;
  location: {
    lat: number;
    lng: number;
  }

  // Objects aren't defined when the class is created so you can not assign values to keys without instantiating the object first
  constructor() {
    this.name = faker.name.firstName()
    this.location = {
      lat: parseFloat(faker.address.longitude()),
      lng: parseFloat(faker.address.latitude())
    } 
  }
}


// Execution - index files:
// index.ts
import faker from 'faker'

// 'export' will export specific variables - imports will be done in curly braces
// 'export default' should nearly never be used in TypeScript - importing default exports won't use curly braces

export class User {
  name: string;
  location: {
    lat: number;
    lng: number;
  }

  // Objects aren't defined when the class is created so you can not assign values to keys without instantiating the object first
  constructor() {
    this.name = faker.name.firstName()
    this.location = {
      lat: parseFloat(faker.address.longitude()),
      lng: parseFloat(faker.address.latitude())
    } 
  }
}

// index.html
// the 'DOCTYPE' heading will cause Google Maps to fail, not sure why
<!-- <!DOCTYPE html> -->
<html>
  <head charset="utf-8">
    <title>Maps</title>
  </head>
  <body>
    <div id="map" style="height: 100%"></div>
    <script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyBNLrJhOMz6idD05pzfn5lhA-TAw-mAZCU"></script>
    <script src="./src/index.ts"></script>
  </body>
</html>

let rand = Math.random()
rand < 0.5 ? gender = 0 : gender = 1
this.name = `${gender ? '👩‍💼' : '👨‍💼'} ${faker.name.firstName(gender)} ${faker.name.lastName(gender)}`

// BASH
mkdir src
mkdir build
touch src/index.ts
touch .gitignore
touch README.md
tsc -y
npm init -y
npm install nodemon concurrently @types/express --save-dev

// package.json
...
"scripts": {
  "start:build": "tsc -w",
  "start:run": "nodemon ./build/index.js",
  "start": "concurrently npm:start:*"
},
...

// tsconfig.json
...
"outDir": "./build",
"rootDir": "./src",
...

// .gitignore
node_modules
*.env

// README.md
### Start
```bash
npm run start
```

// src/index.ts
import express from 'express'
const port = 3000
const app = express()

console.log("Hello, World!!!")

logSomething("This is a string that I'm logging")

app.listen(port, () => {
  console.log(`Listening on port ${port}`)
})

// Bubble sorting using most of the important features in TypeScript

//* index.ts
import { Sorter } from './Sorter';
import { NumbersCollection } from './NumbersCollecton';

// Passing object into helper function to prepare variable for sorter when data is an array
const numbersCollection = new NumbersCollection([10, 3, -5, 0])
// Passing in object now instead of raw data
const sorter = new Sorter(numbersCollection)

sorter.sort()

console.log(numbersCollection.data)



//* Sorter.ts
import { NumbersCollection } from './NumbersCollecton';


export class Sorter {
  constructor(public collection: NumbersCollection)  {}

  sort(): void {
    const { length } = this.collection

    for (let i = 0; i < length; i++) {
      for (let j = 0; j < length - i - 1; j++) {
        if (this.collection.compare(j, j + 1)) {
          this.collection.swap(j, j+1)
        }
        // Only going to work if collecton is a string
        // If collection is a string, do this instead
        // ~~~logic to compare and swap characters in a string
      }
    }
  }
}



//* NumbersCollection.ts

/* Class Structure: */

// File: NumbersCollection.ts
// Class: NumbersCollection {
// Constructor: constructor(permissions, vars: types) {}
// Function(s) function(): type {
  // function body
// } //close function
// } // Close Class




export class NumbersCollection {
  // Require an array of numbers to be passed in and instantiated
  constructor(public data: number[]) {}
  // Need to get length of array
  get length(): number {
    return this.data.length
  }
  // decide if we need to swap 2 elements in a pair (bubble sort)
  /* is -1 > 0 ? If so, swap them
    /       |
  /        |
  [-1] [0] [5] [10] */
  compare(leftIndex: number, rightIndex: number): boolean {
    return this.data[leftIndex] > this.data[rightIndex]
  }

  swap(leftIndex: number, rightIndex: number): void {
    const leftHand = this.data[leftIndex]
    this.data[leftIndex] = this.data[rightIndex]
    this.data[rightIndex] = leftHand

  }

}

// const collection = new NumbersCollection([1,2,3])
// // since 'get' was used, length doesn't need to be called as a function (ex: collection.length())
// collection.length