54 lines
1.5 KiB
C#
54 lines
1.5 KiB
C#
using FluentAssertions;
|
|
using PerfectNumbers.Core.Cpu;
|
|
using Xunit;
|
|
using UInt128 = System.UInt128;
|
|
|
|
namespace PerfectNumbers.Core.Tests;
|
|
|
|
public class MersenneNumberResidueCpuTesterTests
|
|
{
|
|
private static bool LastDigitIsSeven(ulong exponent) => (exponent & 3UL) == 3UL;
|
|
|
|
[Fact]
|
|
[Trait("Category", "Fast")]
|
|
public void Scan_handles_various_prime_exponents()
|
|
{
|
|
var tester = new MersenneNumberResidueCpuTester();
|
|
|
|
RunCase(tester, 23UL, 1UL, expectedPrime: false);
|
|
RunCase(tester, 29UL, 36UL, expectedPrime: false);
|
|
RunCase(tester, 89UL, 1_000UL, expectedPrime: true);
|
|
RunCase(tester, 127UL, 1_000UL, expectedPrime: true);
|
|
}
|
|
|
|
[Fact]
|
|
[Trait("Category", "Fast")]
|
|
public void Scan_recognizes_all_known_small_mersenne_primes()
|
|
{
|
|
var tester = new MersenneNumberResidueCpuTester();
|
|
|
|
foreach (ulong exponent in MersennePrimeTestData.Exponents)
|
|
{
|
|
RunCase(tester, exponent, 1UL, expectedPrime: true);
|
|
}
|
|
}
|
|
|
|
private static void RunCase(MersenneNumberResidueCpuTester tester, ulong exponent, ulong maxK, bool expectedPrime)
|
|
{
|
|
bool isPrime = true;
|
|
bool exhausted = false;
|
|
tester.Scan(
|
|
exponent,
|
|
(UInt128)exponent << 1,
|
|
LastDigitIsSeven(exponent),
|
|
(UInt128)maxK,
|
|
UInt128.One,
|
|
(UInt128)maxK,
|
|
ref isPrime,
|
|
ref exhausted);
|
|
isPrime.Should().Be(expectedPrime);
|
|
exhausted.Should().BeTrue();
|
|
}
|
|
}
|
|
|