MonkeyPatching in Ruby is actually extremely easy to understand and use.
We can monkey patch any ruby class, and this is how to do it.
WHEN WE SHOULD MONKEYPATCH?
- if we want to fix the broken code inside some library
- when we want to check something fast
HOW IT WORKS
For sure we all now reverse method belonging to the Array class.
["a", "b", "c"].reverse => ["c", "b", "a"]
It's quite common, and we use it on daily basis.
If we want to change the use of this method, we can just write in a new file:
# frozen_string_literal: true class Array def reverse raise "Error Blocked" end end ["a", "b", "c"].reverse
It will return an error instead of reversing the array.
BEST WAY TO DO IT
In modern programming people believe that just overriting a class is not a good idea. It can give us a lot of problems.
For example we can monkey patch some method twice - it will be overrited, and we won't know what is happening.
It is good to monkey patch classes inside modules and then include them when we need it.
Check this out: