inactive-users.js

// Candidates

const reduceSpread = (users) => {
	return users.reduce((acc, user) => {
		if (!user.active) {
			return { ...acc, [user.id]: user.name }
		}
		return acc
	}, {})
}

const reduceAssign = (users) => {
	return users.reduce((acc, user) => {
		if (!user.active) {
			return Object.assign(acc, { [user.id]: user.name })
		}
		return acc
	}, {})
}

const reduceIndex = (users) => {
	return users.reduce((acc, user) => {
		if (!user.active) {
			acc[user.id] = user.name
		}
		return acc
	}, {})
}

const filterReduceSpread = (users) => {
	return users
		.filter((user) => !user.active)
		.reduce((acc, user) => ({ ...acc, [user.id]: user.name }), {})
}

const filterReduceAssign = (users) => {
	return users
		.filter((user) => !user.active)
		.reduce((acc, user) => Object.assign(acc, { [user.id]: user.name }), {})
}

const filterReduceIndex = (users) => {
	return users
		.filter((user) => !user.active)
		.reduce((acc, user) => {
			acc[user.id] = user.name
			return acc
		}, {})
}

const filterMapReduceSpread = (users) => {
	return users
		.filter((user) => !user.active)
		.map((user) => ({ [user.id]: user.name }))
		.reduce((acc, user) => ({ ...acc, ...user }), {})
}

const filterMapReduceAssign = (users) => {
	return users
		.filter((user) => !user.active)
		.map((user) => ({ [user.id]: user.name }))
		.reduce((acc, user) => Object.assign(acc, user), {})
}

const filterMapObjectReduceIndex = (users) => {
	return users
		.filter((user) => !user.active)
		.map((user) => ({ [user.id]: user.name }))
		.reduce((acc, user) => {
			acc[user.id] = user.name
			return acc
		}, {})
}

const filterMapEntryReduceIndex = (users) => {
	return users
		.filter((user) => !user.active)
		.map((user) => [user.id, user.name])
		.reduce((acc, [id, name]) => {
			acc[id] = name
			return acc
		}, {})
}

const filterMapEntries = (users) => {
	const entries = users
		.filter((user) => !user.active)
		.map((user) => [user.id, user.name])
	return Object.fromEntries(entries)
}

const whileEntries = (users) => {
	const filtered = []
	const length = users.length
	let idx = -1
	while (++idx < length) {
		const user = users[idx]
		if (!user.active) {
			filtered.push([user.id, user.name])
		}
	}
	return Object.fromEntries(filtered)
}

const whileIndex = (users) => {
	const acc = {}
	const length = users.length
	let idx = -1
	while (++idx < length) {
		const user = users[idx]
		if (!user.active) {
			acc[user.id] = user.name
		}
	}
	return acc
}

const forOfEntries = (users) => {
	const filtered = []
	for (const user of users) {
		if (!user.active) {
			filtered.push([user.id, user.name])
		}
	}
	return Object.fromEntries(filtered)
}

const forOfIndex = (users) => {
	const acc = {}
	for (const user of users) {
		if (!user.active) {
			acc[user.id] = user.name
		}
	}
	return acc
}

const forOfIndexDestructuring = (users) => {
	const acc = {}
	for (const { active, id, name } of users) {
		if (!active) {
			acc[id] = name
		}
	}
	return acc
}

// Data generation

const getUsers = () =>
	[
		"Abbie",
		"Ben",
		"Charlie",
		"Danny",
		"Ellen",
		"Frankie",
		"Gerald",
		"Harriet",
		"Ilene",
		"Janet",
		"Kenny",
		"Lisa",
		"Martin",
		"Nate",
		"Orville",
		"Peter",
		"Quaid",
		"Randy",
		"Sally",
		"Tom",
		"Umberto",
		"Vanessa",
		"Wendy",
		"Xerxes",
		"Yolanda",
		"Zach",
	].map((name) => ({
		name,
		active: !Math.floor(Math.random() * 2),
		id: Math.floor(Math.random() * 1000000),
	}))