Object.assign()

The Object.assign() static method copies all enumerable own properties from one or more source objects to a target object. It returns the modified target object.

Properties in the target object are overwritten by properties in the sources if they have the same key. Later sources’ properties overwrite earlier ones.

The Object.assign() method only copies enumerable and own properties from a source object to a target object. It uses [[Get]] on the source and [[Set]] on the target, so it will invoke getters and setters. Therefore it assigns properties, versus copying or defining new properties. This may make it unsuitable for merging new properties into a prototype if the merge sources contain getters.

Syntax example: Object.assign(target)