assert-equals.js

function assertEquals(expect, actual) {
    // check different data type
    if (typeof expect !== typeof actual && !Array.isArray(expect) && !Array.isArray(actual)) {
        throw new Error(`Expected type ${typeof expect} but found type ${typeof actual}`)
    } else if (Array.isArray(expect) && !Array.isArray(actual)) {
        throw new Error(`Expected type array but found type ${typeof actual}`)
    } else if (!Array.isArray(expect) && Array.isArray(actual)) {
        throw new Error(`Expected type ${typeof expect} but found type array`)
    } else if ((typeof expect === 'object' &&  actual === null) || (typeof actual === 'object' &&  expect === null)) {   
        throw new Error(`It's not the same object`)
    }

    // check data type number
    if (typeof expect === 'number' && typeof actual === 'number') {
        if (expect === actual) {
            console.info('No error')
        } else {
            throw new Error(`Expected ${expect} but found ${actual}`)
        }
    }

    // check data type string
    if (typeof expect === 'string' && typeof actual === 'string') {
        if (expect === actual) {
            console.info('No error')
        } else {
            throw new Error(`Expected "${expect}" but found "${actual}"`)

        }
    }

    //check data type array
    if (Array.isArray(expect) && Array.isArray(actual)) {
        if (expect.length === actual.length) {
            for (let i = 0; i < expect.length; i++) {
                if (expect[i] !== actual[i]) {
                    throw new Error(`Expected "${expect[i]}" but found "${actual[i]}"`)
                }
            }
            console.info('No error')
            return
        } else if (expect.length !== actual.length) {
            throw new Error(`Expected array length ${expect.length} but found ${actual.length}`)

        }
    }

    //check data type object
    if (typeof expect === 'object' && typeof actual === 'object') {
            const key1 = Object.keys(expect)
            const key2 = Object.keys(actual)
            if (key1.length !== key2.length) {
                throw new Error(`Expected and actual object do not have the same length`)
            } else if (key1.length === key2.length) {
                for (let key of key1) {
                    if (expect[key] !== actual[key]) {
                        throw new Error(`Expected and actual object do not have the same key value`)
                    }
                }
                console.info('No error')
            }
        }

}

module.exports = assertEquals