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ruby--ruby/test/test_prime.rb
ayumin bef8e4557c * lib/prime.rb (Prime#prime?): negative numbers can't be primes
by definition. reported by Ivan Kataitsev. [Bug ]
* test/test_prime.rb: add test.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45878 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
2014-05-08 18:22:29 +00:00

174 lines
4.2 KiB
Ruby

require 'test/unit'
require 'prime'
require 'stringio'
require 'timeout'
class TestPrime < Test::Unit::TestCase
# The first 100 prime numbers
PRIMES = [
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37,
41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
89, 97, 101, 103, 107, 109, 113, 127, 131,
137, 139, 149, 151, 157, 163, 167, 173, 179,
181, 191, 193, 197, 199, 211, 223, 227, 229,
233, 239, 241, 251, 257, 263, 269, 271, 277,
281, 283, 293, 307, 311, 313, 317, 331, 337,
347, 349, 353, 359, 367, 373, 379, 383, 389,
397, 401, 409, 419, 421, 431, 433, 439, 443,
449, 457, 461, 463, 467, 479, 487, 491, 499,
503, 509, 521, 523, 541,
]
def test_each
primes = []
Prime.each do |p|
break if p > 541
primes << p
end
assert_equal PRIMES, primes
end
def test_each_by_prime_number_theorem
3.upto(15) do |i|
max = 2**i
primes = []
Prime.each do |p|
break if p >= max
primes << p
end
# Prime number theorem
assert primes.length >= max/Math.log(max)
delta = 0.05
li = (2..max).step(delta).inject(0){|sum,x| sum + delta/Math.log(x)}
assert primes.length <= li
end
end
def test_each_without_block
enum = Prime.each
assert enum.respond_to?(:each)
assert enum.kind_of?(Enumerable)
assert enum.respond_to?(:with_index)
assert enum.respond_to?(:next)
assert enum.respond_to?(:succ)
assert enum.respond_to?(:rewind)
end
def test_new
orig_stderr, orig_verbose = $stderr, $VERBOSE
$stderr = buf = StringIO.new('', 'w')
$VERBOSE = false
enum = Prime.new
assert_match("obsolete", buf.string)
assert enum.respond_to?(:each)
assert enum.kind_of?(Enumerable)
assert enum.respond_to?(:succ)
assert Prime === enum
ensure
$stderr = orig_stderr
$VERBOSE = orig_verbose
end
def test_enumerator_succ
enum = Prime.each
assert_equal PRIMES[0, 50], 50.times.map{ enum.succ }
assert_equal PRIMES[50, 50], 50.times.map{ enum.succ }
enum.rewind
assert_equal PRIMES[0, 100], 100.times.map{ enum.succ }
end
def test_enumerator_with_index
enum = Prime.each
last = -1
enum.with_index do |p,i|
break if i >= 100
assert_equal last+1, i
assert_equal PRIMES[i], p
last = i
end
end
def test_default_instance_does_not_have_compatibility_methods
assert !Prime.instance.respond_to?(:succ)
assert !Prime.instance.respond_to?(:next)
end
class TestInteger < Test::Unit::TestCase
def test_prime_division
pd = PRIMES.inject(&:*).prime_division
assert_equal PRIMES.map{|p| [p, 1]}, pd
pd = (-PRIMES.inject(&:*)).prime_division
assert_equal [-1, *PRIMES].map{|p| [p, 1]}, pd
end
def test_from_prime_division
assert_equal PRIMES.inject(&:*), Integer.from_prime_division(PRIMES.map{|p| [p,1]})
assert_equal(-PRIMES.inject(&:*), Integer.from_prime_division([[-1, 1]] + PRIMES.map{|p| [p,1]}))
end
def test_prime?
# zero and unit
assert !0.prime?
assert !1.prime?
# small primes
assert 2.prime?
assert 3.prime?
# squared prime
assert !4.prime?
assert !9.prime?
# mersenne numbers
assert((2**31-1).prime?)
assert !(2**32-1).prime?
# fermat numbers
assert((2**(2**4)+1).prime?)
assert !(2**(2**5)+1).prime? # Euler!
# large composite
assert !((2**13-1) * (2**17-1)).prime?
# factorial
assert !(2...100).inject(&:*).prime?
# negative
assert !-1.prime?
assert !-2.prime?
assert !-3.prime?
assert !-4.prime?
end
end
def test_eratosthenes_works_fine_after_timeout
sieve = Prime::EratosthenesSieve.instance
sieve.send(:initialize)
begin
# simulates that Timeout.timeout interrupts Prime::EratosthenesSieve#extend_table
def sieve.Integer(n)
n = super(n)
sleep 10 if /compute_primes/ =~ caller.first
return n
end
begin
Timeout.timeout(0.5) { Prime.each(7*37){} }
flunk("timeout expected")
rescue Timeout::Error
end
ensure
class << sieve
remove_method :Integer
end
end
assert_not_include Prime.each(7*37).to_a, 7*37, "[ruby-dev:39465]"
end
end