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git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62656 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
17 lines
481 B
Ruby
17 lines
481 B
Ruby
require_relative '../../../spec_helper'
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require 'prime'
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describe "Integer#prime?" do
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it "returns a true value for prime numbers" do
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2.prime?.should be_true
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3.prime?.should be_true
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(2**31-1).prime?.should be_true # 8th Mersenne prime (M8)
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end
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it "returns a false value for composite numbers" do
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4.prime?.should be_false
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15.prime?.should be_false
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(2**32-1).prime?.should be_false
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( (2**17-1)*(2**19-1) ).prime?.should be_false # M6*M7
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end
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end
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