class RuboCop::Cop::Rails::Present

something if foo.present?
# good
something unless foo.blank?
# bad
# UnlessBlank: true
foo.present?
# good
not foo.blank?
!foo.blank?
# bad
# NotBlank: true
foo.present?
# good
!foo.blank?
foo != nil && !foo.empty?
!foo.nil? && !foo.empty?
# bad
# NotNilAndNotEmpty: true
@example
UnlessBlank: Convert usages of ‘unless` `blank?` to `if` `present?`
NotBlank: Convert usages of not `blank?` to `present?`
to `present?`
NotNilAndNotEmpty: Convert checks for not `nil` and `not empty?`
Settings:
This cops checks for code that can be changed to `blank?`.

def autocorrect(node) 

def autocorrect(node)
  lambda do |corrector|
    method_call, variable1 = unless_blank?(node)
    if method_call
      corrector.replace(node.loc.keyword, 'if')
      range = method_call.loc.expression
    else
      variable1, _variable2 =
        exists_and_not_empty?(node) || not_blank?(node)
      range = node.loc.expression
    end
    corrector.replace(range, replacement(variable1))
  end
end

def on_and(node) 

def on_and(node)
  return unless cop_config['NotNilAndNotEmpty']
  exists_and_not_empty?(node) do |variable1, variable2|
    return unless variable1 == variable2
    add_offense(node,
                message: format(MSG_EXISTS_AND_NOT_EMPTY,
                                prefer: replacement(variable1),
                                current: node.source))
  end
end

def on_if(node) 

def on_if(node)
  return unless cop_config['UnlessBlank']
  return unless node.unless?
  unless_blank?(node) do |method_call, receiver|
    range = unless_condition(node, method_call)
    msg = format(MSG_UNLESS_BLANK, prefer: replacement(receiver),
                                   current: range.source)
    add_offense(node, location: range, message: msg)
  end
end

def on_or(node) 

def on_or(node)
  return unless cop_config['NilOrEmpty']
  exists_and_not_empty?(node) do |variable1, variable2|
    return unless variable1 == variable2
    add_offense(node, message: MSG_EXISTS_AND_NOT_EMPTY)
  end
end

def on_send(node) 

def on_send(node)
  return unless cop_config['NotBlank']
  not_blank?(node) do |receiver|
    add_offense(node,
                message: format(MSG_NOT_BLANK,
                                prefer: replacement(receiver),
                                current: node.source))
  end
end

def replacement(node) 

def replacement(node)
  node.respond_to?(:source) ? "#{node.source}.present?" : 'present?'
end

def unless_condition(node, method_call) 

def unless_condition(node, method_call)
  if node.modifier_form?
    node.loc.keyword.join(node.loc.expression.end)
  else
    node.loc.expression.begin.join(method_call.loc.expression)
  end
end