Issue #31: implement mxstatus proxy and hresult conversion

src/MxGateway.Worker.Tests/Conversion/HResultConverterTests.cs

@@ -0,0 +1,47 @@
+using System;
+using System.Runtime.InteropServices;
+using MxGateway.Contracts.Proto;
+using MxGateway.Worker.Conversion;
+
+namespace MxGateway.Worker.Tests.Conversion;
+
+public sealed class HResultConverterTests
+{
+    private readonly HResultConverter _converter = new();
+
+    [Fact]
+    public void Convert_WithComException_CapturesExceptionHResult()
+    {
+        COMException exception = new("Sensitive provider text should not be copied.", unchecked((int)0x80070057));
+
+        HResultConversion converted = _converter.Convert(exception);
+
+        Assert.Equal(unchecked((int)0x80070057), converted.HResult);
+        Assert.Equal(ProtocolStatusCode.MxaccessFailure, converted.ProtocolStatus.Code);
+        Assert.Contains("0x80070057", converted.ProtocolStatus.Message);
+        Assert.Contains(typeof(COMException).FullName!, converted.DiagnosticMessage);
+        Assert.DoesNotContain("Sensitive provider text", converted.DiagnosticMessage);
+    }
+
+    [Fact]
+    public void CreateProtocolStatus_WithSuccessHResult_ReturnsOk()
+    {
+        ProtocolStatus status = _converter.CreateProtocolStatus(0);
+
+        Assert.Equal(ProtocolStatusCode.Ok, status.Code);
+        Assert.Equal("HRESULT 0x00000000", status.Message);
+    }
+
+    [Fact]
+    public void Convert_WithNonComException_CapturesExceptionHResult()
+    {
+        InvalidOperationException exception = new("do not include this");
+
+        HResultConversion converted = _converter.Convert(exception);
+
+        Assert.Equal(exception.HResult, converted.HResult);
+        Assert.Equal(ProtocolStatusCode.MxaccessFailure, converted.ProtocolStatus.Code);
+        Assert.Contains("0x", converted.DiagnosticMessage);
+        Assert.DoesNotContain("do not include this", converted.DiagnosticMessage);
+    }
+}