#28: Synergy.Contracts: Test files rename

Also changed NUnit to XUnit

Contracts/Synergy.Contracts.Test/Failures/Because/Fail.Because.cs

@@ -0,0 +1,80 @@
+using Synergy.Contracts.Samples.Domain;
+using Xunit;
+
+namespace Synergy.Contracts.Test.Failures.Because;
+
+public class FailBecauseTest
+{
+    [Fact]
+    public void BecauseWith0Arguments()
+    {
+        // ACT
+        var exception = Fail.Because("Always");
+
+        // ASSERT
+        Assert.NotNull(exception);
+        Assert.Equal("Always", exception.Message);
+    }
+
+    [Fact]
+    public void BecauseWith1Argument()
+    {
+        // ACT
+        // ReSharper disable once HeapView.BoxingAllocation
+        var exception = Fail.Because("Always {0}", 1);
+
+        // ASSERT
+        Assert.NotNull(exception);
+        Assert.Equal("Always 1", exception.Message);
+    }
+
+    [Fact]
+    public void BecauseWith2Arguments()
+    {
+        // ACT
+        // ReSharper disable once HeapView.BoxingAllocation
+        var exception = Fail.Because("Always {0} {1}", "fails", 1);
+
+        // ASSERT
+        Assert.NotNull(exception);
+        Assert.Equal("Always fails 1", exception.Message);
+    }
+
+    [Fact]
+    public void BecauseWith3Arguments()
+    {
+        // ACT
+        // ReSharper disable once HeapView.BoxingAllocation
+        var exception = Fail.Because("Always {0} {1} {2}", "fails", 1, "times");
+
+        // ASSERT
+        Assert.NotNull(exception);
+        Assert.Equal("Always fails 1 times", exception.Message);
+    }
+
+    [Fact]
+    public void BecauseWithNArguments()
+    {
+        // ACT
+        // ReSharper disable once HeapView.BoxingAllocation
+        var exception = Fail.Because("Always {0} {1} {2} {3}", "fails", 1, "times", "frequently");
+
+        // ASSERT
+        Assert.NotNull(exception);
+        Assert.Equal("Always fails 1 times frequently", exception.Message);
+    }
+
+    [Fact]
+    public void BecauseSample()
+    {
+        // ARRANGE
+        var contractor = new Contractor();
+
+        // ACT
+        var exception = Assert.Throws<DesignByContractViolationException>(
+            () => contractor.SetPersonName("Marcin", "Celej"));
+
+        // ASSERT
+        Assert.Equal("Not implemented yet", exception.Message);
+    }
+}