module Nesting

# File lib/nesting.rb, line 3
def of(mod)
  if nonmodule?(mod)
    raise TypeError, 'mod is not a class or module'
  end

  level = 0

  # Special case Object as it's the namespace of all classes.
  return level if mod == Object

  level = if mod.name
            mod.name.split('::').count
          else
            -1 # Probably an anonymous module.
          end

  level
end

# File lib/nesting.rb, line 22
def parents(mod)
  if nonmodule?(mod)
    raise TypeError, 'mod is not a class or module'
  end

  parents = []

  return nil if mod == Object

  if mod.name
    mod.name.split('::')[0..-2].inject(Object) do |parent, child|
      const = parent.const_get(child)
      parents << const
      const
    end
    parents.reverse! << Object
  else
    parents = nil # Probably an anonymous module.
  end

  parents
end

# File lib/nesting.rb, line 47
def nonmodule?(mod)
  !((mod.class == Module) ^ (mod.class == Class))
end