class RSpec::Core::ExampleGroup

def self.method_missing(name, *args)
  if method_defined?(name)
    raise WrongScopeError,
          "`#{name}` is not available on an example group (e.g. a " \
          "`describe` or `context` block). It is only available from " \
          "within individual examples (e.g. `it` blocks) or from " \
          "constructs that run in the scope of an example (e.g. " \
          "`before`, `let`, etc)."
  end
  super
end