Initial commit.

PerfectNumbers.Core.Tests/MersenneNumberResidueGpuTesterTests.cs

@@ -0,0 +1,33 @@
+using FluentAssertions;
+using PerfectNumbers.Core.Gpu;
+using Xunit;
+using UInt128 = System.UInt128;
+
+namespace PerfectNumbers.Core.Tests;
+
+public class MersenneNumberResidueGpuTesterTests
+{
+    private static bool LastDigitIsSeven(ulong exponent) => (exponent & 3UL) == 3UL;
+
+    [Theory]
+    [InlineData(false)]
+    [InlineData(true)]
+    [Trait("Category", "Fast")]
+    public void Scan_handles_various_prime_exponents(bool useGpuOrder)
+    {
+        var tester = new MersenneNumberResidueGpuTester(useGpuOrder);
+
+        RunCase(tester, 23UL, 2UL, expectedPrime: false);
+        RunCase(tester, 29UL, 37UL, expectedPrime: false);
+        RunCase(tester, 89UL, 1_001UL, expectedPrime: true);
+        RunCase(tester, 127UL, 1_001UL, expectedPrime: true);
+    }
+
+    private static void RunCase(MersenneNumberResidueGpuTester tester, ulong exponent, ulong maxK, bool expectedPrime)
+    {
+        bool isPrime = true;
+        tester.Scan(exponent, (UInt128)exponent << 1, LastDigitIsSeven(exponent), (UInt128)maxK, ref isPrime);
+        isPrime.Should().Be(expectedPrime);
+    }
+}
+