class RuboCop::Cop::Style::IdenticalConditionalBranches

def expand_elses(branch)

need to recursively iterate over all `else` branches.
`elsif` branches show up in the if node as nested `else` branches. We 
def expand_elses(branch)
  if branch.nil?
    [nil]
  elsif branch.if_type?
    _condition, elsif_branch, else_branch = *branch
    expand_elses(else_branch).unshift(elsif_branch)
  else
    [branch]
  end
end