Write a transformStateWithClones
function that takes a state
object and an actions
array,
applies each action to the previos state
to calculate the next state,
and returns an array with states recieved after each action.
Each action
is an object describing state
changes. Depending on a value of its type
property you should do the next:
clear
- create an empty state object;addProperties
- add allkey: value
pairs given inextraData
property to the newstate
;removeProperties
- remove all keys given in thekeysToRemove
array from thestate
. (ignore not existing)
IMPORTANT! DON'T modify the initial state
object in any way!
Example 1:
const state = {
foo: 'bar',
bar: 'foo',
};
const stateHistory = transformStateWithClones(state, [
{
type: 'addProperties',
extraData: { name: 'Jim', hello: 'world' },
},
{
type: 'removeProperties',
keysToRemove: ['bar', 'hello'],
},
{
type: 'addProperties',
extraData: { another: 'one' },
},
]);
console.log(stateHistory);
// [
// { foo: 'bar', bar: 'foo', name: 'Jim', hello: 'world' },
// { foo: 'bar', name: 'Jim' },
// { foo: 'bar', name: 'Jim', another: 'one' },
// ]
Example 2:
const state = {
foo: 'bar',
bar: 'foo',
};
const stateHistory = transformStateWithClones(state, [
{
type: 'addProperties',
extraData: { yet: 'another property' },
}
{ type: 'clear' },
{
type: 'addProperties',
extraData: { foo: 'bar', name: 'Jim' },
},
]);
console.log(stateHistory);
// [
// { foo: 'bar', bar: 'foo', yet: 'another property' },
// {},
// { foo: 'bar', name: 'Jim' },
// ]
Read the guideline before start