mergeAndCombineConsumptions.ts

/*
    use case of how to merge 2 similat objects arrays into a new object array
    combining the data from them
*/

const ConsumptionType = {
    TYPE_1: 'TYPE_1_VALUE',
    TYPE_2: 'TYPE_2_VALUE'
} as const satisfies Record<string, string>

type TConsumptionTypeKeys = keyof typeof ConsumptionType;
type TConsumptionType = typeof ConsumptionType[TConsumptionTypeKeys];

interface ITimeRef {
    startedAt: string;
    endedAt: string;
}

interface IConsumption extends ITimeRef {
    amount: number;
    type: TConsumptionType;
}

type TCombinedAmountEntry = [TConsumptionType, number];

interface IConsumptionMerged extends ITimeRef {
    amounts: TCombinedAmountEntry[];
}

//---------------------------------------------------------------------//
// @begin: merging logic

const mergeAndCombineConsumptions = (...args: IConsumption[][]) => {
    const combinedMap = new Map<string, IConsumptionMerged>()

    args.forEach(consumptions => {
        consumptions.forEach(consumption => {
            const { startedAt, endedAt, amount, type } = consumption;
            if(!combinedMap.has(startedAt)) {
                combinedMap.set(startedAt, {
                    startedAt,
                    endedAt,
                    amounts: [
                        [type, amount]
                    ]
                });
            } else {
                const combinedConsumption = combinedMap.get(startedAt)!;
                combinedConsumption.amounts.push([type, amount]);
            }
        })
    })

    return Array.from(combinedMap.values());
}

// @end: merging logic
//---------------------------------------------------------------------//
// @begin: mocked data

const consumptions1: IConsumption[] = [
    { startedAt: '20240101', endedAt: '20240201', amount: 2, type: ConsumptionType.TYPE_1 },
    { startedAt: '20240201', endedAt: '20240301', amount: 1.1, type: ConsumptionType.TYPE_1 }
];

const consumptions2: IConsumption[] = [
    { startedAt: '20240201', endedAt: '20240301', amount: 1.2, type: ConsumptionType.TYPE_2 },
    { startedAt: '20240301', endedAt: '20240401', amount: 2, type: ConsumptionType.TYPE_2 }
];

// @end: mocked data
//---------------------------------------------------------------------//

console.log(
    mergeAndCombineConsumptions(
        consumptions1,
        consumptions2
    )
);
  
/* output:
[{
  "startedAt": "20240101",
  "endedAt": "20240201",
  "amounts": [
    [
      "TYPE_1_VALUE",
      2
    ]
  ]
}, {
  "startedAt": "20240201",
  "endedAt": "20240301",
  "amounts": [
    [
      "TYPE_1_VALUE",
      1.1
    ],
    [
      "TYPE_2_VALUE",
      1.2
    ]
  ]
}, {
  "startedAt": "20240301",
  "endedAt": "20240401",
  "amounts": [
    [
      "TYPE_2_VALUE",
      2
    ]
  ]
}]
*/

// TypeScript Playground
// https://www.typescriptlang.org/play/?#code/PQKgUABFEK4M4FMIGMCGiIHsBmEAWmA7hAC6YQC2CATgOZIBMEcAlhSwDaolYBGAVgmQk4EVNWqoAnqJYA7MmIhyExTAKE9xkqZGjJMFXvPm1SeJABNuqCNmqHzCCmBDAwYA3Lg8Awpm8YCgAHEhYAgBUpYKQAXggAbz0oCIBNAAUAUQB9AEYALggAcjSsvOyANQBBABkAVUyigBpkiFKchkKSjI7K2oaisABfMVEvH2ZuFjhsFgRRACUhTGpLAB4falMm5hItuVoAPg8SaKQI-0CQsMizgGkEGQh4gGtHnFIzj8u4INDwuRRGIAbjApxibR+fxugLOz0+MW+AV+1wBQIQAG0LsjoWj7o84ABdUFgeQkGjYVDIJAASQibAQS1wSWgu3E5MsVRIhU2plBrIQcksCE53N2+1ooKGHjJFKptKhqICEAQAA9yULRHSGUzEq1UBRMDAFIU5EFeDR+dBwQhCtirv9biDhic4dijPIRVVDcaSJkFNQpPCsYrHbCYjszUYaMSZQo5dSIDTQzCALI0eiWFXqwWWLX0qi6lnQA1GhRwO3+D0qTk+hT+vZSDGx6VgYDAAC0Xe7Pd7ff7A8HQ+H3fbbeAEAAAhbaPJClQ6KYIBxMLPkB5xjwF-QqkKq8YVCmAaJ4gAKAB0l-EtArSaPAWbzYAlM9DnrWZuUIYDyLU6hgvCKjEH+wQbHs2x3jiSpyOmdAiocp5Ph4rLXnA57YCsmRUngp7jLiyKvu+rL6FBYZoRh1BYcgOF4dBhHFsRxGfgkbLUByXI7LmXokDspa+jsNoQCM8S0WGVqMayLDYKeACEBjVr+-7nng6Cnj47LcU+L4MRJjHyT+lggeeiAkGpJAaaKOw6bpunqWx3EtDZTkqkKDmtM5xF8eWhQYu5HkSRiNq8XWJCEn5-kQGFEVQEMT7iTZIwIBwGDWc5n76Z6lj3nI8IZTWRn0KZdnsSQT4yfFHl5SK2Xnl5IjnsE8A4YFZzBWWoVxeFxHSrpsWtH1rTUAgJAwNQOVVBI0joQ4FC4d+mVGQAbqgHAwPMiGda27ZTrm84ZkuK5ruOI4nadZ1nWO23Tggs5yPOmDIG8WbWOZG7IjwokwnABSQQ6MLNsGrQscV3FdAwAAMDAACzg7ksPNC5wqimDkMwxDuQI3VhQMAJZyFNl6Lnu0eRCY50DA+Z9nI8UEPQ5D8Oca51NFLTMMAMwM2IIWFLk565LjMT46RMKE8TuRCWAsaeO9X5-cenS-SiYYA-EvmshTFlcijdPowjXHM6z4McxjbW+jz544witoQATZxEz02RMEMZNQBrVNazTqNG5z+seyzXswybXPtdjAvW7bMT22UTuSySV27ZQD1PRAL2oMd50Z5nGdjtL3iYBwCDnodp6tNuCC7ll82HsLx4l7pn3HvzXUN8iDCtEhcVAA

mergeAndCombineUsers.ts

/*
  Method 3: Merging and Combining Properties

  source: https://www.spguides.com/typescript-array-concatenation/
*/

interface User {
  id: number;
  name?: string;
  email?: string;
}

const array1: User[] = [
  { id: 1, name: 'Alice' },
  { id: 2, name: 'Bob', email: '[email protected]' }
];

const array2: User[] = [
  { id: 3, name: 'Charlie', email: '[email protected]' },
  { id: 4, name: 'David', email: '[email protected]' },
  { id: 1, email: '[email protected]' },
];

const mergeAndCombine = (arr1: User[], arr2: User[]): User[] => {
  const combinedMap = new Map<number, User>();

  [...arr1, ...arr2].forEach(user => {
    if (!combinedMap.has(user.id)) {
      combinedMap.set(user.id, user);
    } else {
      combinedMap.set(user.id, { ...combinedMap.get(user.id), ...user });
    }
  });

  return Array.from(combinedMap.values());
};

const combinedMergedArray = mergeAndCombine(array1, array2);
console.log(combinedMergedArray);