mspec/lib/mspec/matchers/be_empty.rb
class BeEmptyMatcher
def matches?(actual)
@actual = actual
@actual.empty?
end
def failure_message
["Expected #{@actual.inspect}", "to be empty"]
end
def negative_failure_message
["Expected #{@actual.inspect}", "not to be empty"]
end
end
class Object
def be_empty
BeEmptyMatcher.new
end
end