Run results for: Lodash Custom Merge raf

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.157 Safari/537.36

Browser: Chrome 74

Operating system: Mac OS X 10.14.3

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
them	2250407.0 Ops/sec
raf	0.0 Ops/sec
me	632335.8 Ops/sec

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

function isObject(item) {
    return item && typeof item === 'object' && !Array.isArray(item)
  }


function themeMerge(target, source) {
  

  let output = Object.assign({}, target)
  if (isObject(target) && isObject(source)) {
    Object.keys(source).forEach(key => {
      if (isObject(source[key])) {
        if (!(key in target)) Object.assign(output, { [key]: source[key] })
        else output[key] = themeMerge(target[key], source[key])
      } else {
        Object.assign(output, { [key]: source[key] })
      }
    })
  }
  return output
}

function emptyTarget(val) {
	return Array.isArray(val) ? [] : {}
}

function cloneUnlessOtherwiseSpecified(value, options) {
	return (options.clone !== false && options.isObject(value))
		? deepmerge(emptyTarget(value), value, options)
		: value
}

function defaultArrayMerge(target, source, options) {
	return target.concat(source).map(function(element) {
		return cloneUnlessOtherwiseSpecified(element, options)
	})
}

function getMergeFunction(key, options) {
	if (!options.customMerge) {
		return deepmerge
	}
	var customMerge = options.customMerge(key)
	return typeof customMerge === 'function' ? customMerge : deepmerge
}

function mergeObject(target, source, options) {
	var destination = {}
	if (options.isObject(target)) {
		Object.keys(target).forEach(function(key) {
			destination[key] = cloneUnlessOtherwiseSpecified(target[key], options)
		})
	}
	Object.keys(source).forEach(function(key) {
		if (!options.isObject(source[key]) || !target[key]) {
			destination[key] = cloneUnlessOtherwiseSpecified(source[key], options)
		} else {
			destination[key] = getMergeFunction(key, options)(target[key], source[key], options)
		}
	})
	return destination
}

function deepmerge(target, source, options) {
	options = options || {}
	options.arrayMerge = options.arrayMerge
	options.isObject = options.isObject

	var sourceIsArray = Array.isArray(source)
	var targetIsArray = Array.isArray(target)
	var sourceAndTargetTypesMatch = sourceIsArray === targetIsArray

	if (!sourceAndTargetTypesMatch) {
		return cloneUnlessOtherwiseSpecified(source, options)
	} else if (sourceIsArray) {
		return options.arrayMerge(target, source, options)
	} else {
		return mergeObject(target, source, options)
	}
}

Tests:

them
var a = { a: 'oh', b: 'my' }; var b = { c: 'goddess' }; var c = _.merge(a, b);
raf
var a = { a: 'oh', b: 'my' }; var b = { c: 'goddess' }; var c = merge(a, b);
me
var a = { a: 'oh', b: 'my' }; var b = { c: 'goddess' }; var c = themeMerge(a, b);