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# This is in 1.2.0 with Spec::Matchers.create but it's changing to
# Spec::Matchers.define in 1.2.3. Spec::Matchers.create will remain
# supported, but deprecated, until 1.3.
Spec::Matchers.define :one_more_than do |expected|
  match do |actual|
    actual == expected + 1
  end
end