codeclimate/codeclimate-rubocop

This cop checks for redundant uses of `self`.

The usage of `self` is only needed when:

* Sending a message to same object with zero arguments in
    presence of a method name clash with an argument or a local
    variable.

* Calling an attribute writer to prevent an local variable assignment.

Note, with using explicit self you can only send messages with public or
protected scope, you cannot send private messages this way.

Note we allow uses of `self` with operators because it would be awkward
otherwise.

### Example:

    # bad
    def foo(bar)
      self.baz
    end

    # good
    def foo(bar)
      self.bar  # Resolves name clash with the argument.
    end

    def foo
      bar = 1
      self.bar  # Resolves name clash with the local variable.
    end

    def foo
      %w[x y z].select do |bar|
        self.bar == bar  # Resolves name clash with argument of the block.
      end
    end