This method is only available on newer versions.
The first available version (v2_6_3) is shown here.
hash()
public
When overriding `hash` please preserve the behaviour as mentioned in
docstring for `==` method, i.e. two methods equal by above comparison
should have same hash.
# File lib/bundler/plugin/api/source.rb, line 218
def hash
[self.class, uri].hash
end