UA-.NETStandard/tests/Opc.Ua.Server.Tests/FileSystem/FileObjectStateTests.cs

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using System;
using System.IO;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Moq;
using NUnit.Framework;
using Opc.Ua.Server.FileSystem;
using Opc.Ua.Server.Tests.NodeManager;
using Opc.Ua.Tests;

namespace Opc.Ua.Server.Tests.FileSystem
{
    /// <summary>
    /// Deterministic offline tests for <see cref="FileObjectState"/> that drive
    /// the FileType method handlers (Open/Read/Write/Close/Get/SetPosition), the
    /// metadata property read hooks and the browser population against a physical
    /// provider rooted at a temp directory.
    /// </summary>
    [TestFixture]
    [Category("FileSystem")]
    public class FileObjectStateTests
    {
        private string m_root = null!;
        private ITelemetryContext m_telemetry = null!;
        private FileSystemNodeManager m_manager = null!;
        private ISystemContext m_context = null!;
        private Mock<ISession> m_session = null!;
        private NodeId m_sessionId;

        [SetUp]
        public void SetUp()
        {
            m_root = Path.Combine(Path.GetTempPath(), "fos-" + Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(m_root);
            m_telemetry = NUnitTelemetryContext.Create();

            Mock<IServerInternal> mockServer = DeterministicServerMock.Create(out _);
            mockServer.Setup(s => s.Telemetry).Returns(m_telemetry);
            var provider = new PhysicalFileSystemProvider(m_root, "TestMount");
            m_manager = new FileSystemNodeManager(mockServer.Object, new ApplicationConfiguration(), provider);
            m_sessionId = new NodeId("file-session", 0);
            m_session = CreateSession(m_sessionId);
            m_context = m_manager.SystemContext.Copy(m_session.Object);
        }

        [TearDown]
        public void TearDown()
        {
            m_manager?.Dispose();
            try
            {
                if (Directory.Exists(m_root))
                {
                    Directory.Delete(m_root, recursive: true);
                }
            }
            catch (IOException)
            {
                // best-effort
            }
        }

        private FileObjectState CreateFileState(string providerPath, string? content = null)
        {
            string full = Path.Combine(m_root, providerPath.Replace('/', Path.DirectorySeparatorChar));
            Directory.CreateDirectory(Path.GetDirectoryName(full)!);
            File.WriteAllText(full, content ?? string.Empty);
            NodeId nodeId = FileSystemNodeId.BuildFile(providerPath, m_manager.NamespaceIndex);
            return new FileObjectState(m_context, nodeId, providerPath, Path.GetFileName(providerPath));
        }

        private static Mock<ISession> CreateSession(NodeId sessionId)
        {
            var session = new Mock<ISession>();
            session.Setup(s => s.Id).Returns(sessionId);
            session.Setup(s => s.Identity).Returns(Mock.Of<IUserIdentity>(i => i.TokenType == UserTokenType.UserName));
            session.Setup(s => s.PreferredLocales).Returns([]);
            return session;
        }

        [Test]
        public void OpenForReadThenReadReturnsFileContent()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            uint fileHandle = 0;
            ServiceResult openResult = state.Open!.OnCall!(
                m_context, state.Open, state.NodeId, 0x1, ref fileHandle);

            Assert.That(ServiceResult.IsGood(openResult), Is.True);
            Assert.That(fileHandle, Is.GreaterThan(0u));

            ByteString data = default;
            ServiceResult readResult = state.Read!.OnCall!(
                m_context, state.Read, state.NodeId, fileHandle, 5, ref data);

            Assert.That(ServiceResult.IsGood(readResult), Is.True);
            Assert.That(Encoding.UTF8.GetString(data.ToArray()), Is.EqualTo("hello"));
        }

        [Test]
        public void OpenReturnsDistinctOpaqueHandles()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            uint firstHandle = 0;
            uint secondHandle = 0;
            ServiceResult firstResult = state.Open!.OnCall!(
                m_context, state.Open, state.NodeId, 0x1, ref firstHandle);
            ServiceResult secondResult = state.Open.OnCall!(
                m_context, state.Open, state.NodeId, 0x1, ref secondHandle);

            Assert.That(ServiceResult.IsGood(firstResult), Is.True);
            Assert.That(ServiceResult.IsGood(secondResult), Is.True);
            Assert.That(firstHandle, Is.Not.Zero);
            Assert.That(secondHandle, Is.Not.Zero);
            Assert.That(secondHandle, Is.Not.EqualTo(firstHandle));
        }

        [TestCase("DATA.TXT")]
        [TestCase("data.txt.")]
        [TestCase("data.txt.. ")]
        public async Task FileAliasesShareOpenCountAndWriterExclusionOnWindowsAsync(string alternatePath)
        {
            FileObjectState original = CreateFileState("data.txt", "payload");
            bool sameFile = Path.DirectorySeparatorChar == '\\';
            if (!sameFile)
            {
                // Unix mounts can also be case-insensitive; these are deliberately distinct entries.
                alternatePath = "distinct-" + alternatePath;
                await m_manager.Provider.CreateFileAsync(alternatePath, CancellationToken.None).ConfigureAwait(false);
            }
            var alternate = new FileObjectState(m_context,
                FileSystemNodeId.BuildFile(alternatePath, m_manager.NamespaceIndex), alternatePath, alternatePath);
            uint opened = await FileReadRegressionTests.OpenAsync(original, m_context, 2).ConfigureAwait(false);

            (ServiceResult result, DataValue value) = await alternate.OpenCount!.ReadAttributeAsync(
                m_context, Attributes.Value, NumericRange.Null, QualifiedName.Null, default).ConfigureAwait(false);

            Assert.That(result.StatusCode, Is.EqualTo(StatusCodes.Good));
            Assert.That(value.WrappedValue.TryGetValue(out ushort count), Is.True);
            Assert.That(count, Is.EqualTo(sameFile ? 1 : 0));
            if (sameFile)
            {
                OpenMethodStateResult second = await alternate.Open!.OnCallAsync!(
                    m_context, alternate.Open, alternate.NodeId, 6, CancellationToken.None).ConfigureAwait(false);
                Assert.That(second.ServiceResult.StatusCode, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(second.FileHandle, Is.Zero);
            }

            FileState closingFile = sameFile ? alternate : original;
            Assert.That(closingFile.Close!.OnCall!(
                m_context, closingFile.Close, closingFile.NodeId, opened).StatusCode, Is.EqualTo(StatusCodes.Good));
        }

        [TestCase(BrowseNames.Size)]
        [TestCase(BrowseNames.MimeType)]
        [TestCase(BrowseNames.LastModifiedTime)]
        [TestCase(BrowseNames.Writable)]
        [TestCase(BrowseNames.UserWritable)]
        [TestCase(BrowseNames.OpenCount)]
        public async Task MetadataReadsDoNotRetainFileHandleStateAsync(string property)
        {
            for (int ii = 0; ii < 128; ii++)
            {
                FileObjectState file = CreateFileState("metadata-" + ii + ".txt", "payload");
                NodeState variable = file.FindChild(m_context, new QualifiedName(property))!;
                (ServiceResult result, DataValue value) = await variable.ReadAttributeAsync(
                    m_context, Attributes.Value, NumericRange.Null, QualifiedName.Null, default).ConfigureAwait(false);
                Assert.That(result.StatusCode, Is.EqualTo(
                    property == BrowseNames.MimeType ? StatusCodes.Uncertain : StatusCodes.Good));
                Assert.That(value.StatusCode, Is.EqualTo(
                    property == BrowseNames.MimeType ? StatusCodes.Uncertain : StatusCodes.Good));
            }

            Assert.That(m_manager.TrackedFileCount, Is.Zero,
                "Read-only metadata requests must not retain one handle bag per requested path.");
        }

        [Test]
        public async Task ClosingTheLastStreamReleasesIdleFileHandleStateAsync()
        {
            for (int ii = 0; ii < 32; ii++)
            {
                FileObjectState file = CreateFileState("open-" + ii + ".txt", "payload");
                uint opened = await FileReadRegressionTests.OpenAsync(file, m_context).ConfigureAwait(false);
                Assert.That(m_manager.TrackedFileCount, Is.EqualTo(1));
                Assert.That(file.Close!.OnCall!(m_context, file.Close, file.NodeId, opened).StatusCode,
                    Is.EqualTo(StatusCodes.Good));
                Assert.That(m_manager.TrackedFileCount, Is.Zero);
            }
        }

        [Test]
        public void OpenWithoutSessionReturnsBadSessionIdInvalid()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            ISystemContext contextWithoutSession = m_manager.SystemContext.Copy();

            uint fileHandle = 0;
            ServiceResult result = state.Open!.OnCall!(
                contextWithoutSession, state.Open, state.NodeId, 0x1, ref fileHandle);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadSessionIdInvalid));
            Assert.That(fileHandle, Is.Zero);
        }

        [Test]
        public void CloseWithoutSessionReturnsBadSessionIdInvalid()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x1, ref fileHandle);
            ISystemContext contextWithoutSession = m_manager.SystemContext.Copy();

            ServiceResult result = state.Close!.OnCall!(
                contextWithoutSession, state.Close, state.NodeId, fileHandle);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadSessionIdInvalid));
        }

        [Test]
        public void SetPositionWithoutSessionReturnsBadSessionIdInvalid()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x1, ref fileHandle);
            ISystemContext contextWithoutSession = m_manager.SystemContext.Copy();

            ServiceResult result = state.SetPosition!.OnCall!(
                contextWithoutSession, state.SetPosition, state.NodeId, fileHandle, 1u);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadSessionIdInvalid));
        }

        [Test]
        public void GetPositionWithoutSessionReturnsBadSessionIdInvalid()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x1, ref fileHandle);
            ISystemContext contextWithoutSession = m_manager.SystemContext.Copy();

            ulong position = 0;
            ServiceResult result = state.GetPosition!.OnCall!(
                contextWithoutSession, state.GetPosition, state.NodeId, fileHandle, ref position);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadSessionIdInvalid));
        }

        [Test]
        public void ReadWithoutSessionReturnsBadSessionIdInvalid()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x1, ref fileHandle);
            ISystemContext contextWithoutSession = m_manager.SystemContext.Copy();

            ByteString data = default;
            ServiceResult result = state.Read!.OnCall!(
                contextWithoutSession, state.Read, state.NodeId, fileHandle, 1, ref data);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadSessionIdInvalid));
        }

        [Test]
        public void WriteWithoutSessionReturnsBadSessionIdInvalid()
        {
            FileObjectState state = CreateFileState("out.txt");
            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x2, ref fileHandle);
            ISystemContext contextWithoutSession = m_manager.SystemContext.Copy();

            var payload = ByteString.From([1, 2, 3]);
            ServiceResult result = state.Write!.OnCall!(
                contextWithoutSession, state.Write, state.NodeId, fileHandle, payload);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadSessionIdInvalid));
        }

        [Test]
        public void FileHandleMethodsRejectDifferentSession()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            uint fileHandle = 0;
            ServiceResult openResult = state.Open!.OnCall!(
                m_context, state.Open, state.NodeId, 0x1, ref fileHandle);
            Assert.That(ServiceResult.IsGood(openResult), Is.True);

            Mock<ISession> otherSession = CreateSession(new NodeId("other-file-session", 0));
            ISystemContext otherContext = m_manager.SystemContext.Copy(otherSession.Object);

            ByteString data = default;
            ServiceResult readResult = state.Read!.OnCall!(
                otherContext, state.Read, state.NodeId, fileHandle, 1, ref data);
            var payload = ByteString.From([1]);
            ServiceResult writeResult = state.Write!.OnCall!(
                otherContext, state.Write, state.NodeId, fileHandle, payload);
            ulong position = 0;
            ServiceResult getPositionResult = state.GetPosition!.OnCall!(
                otherContext, state.GetPosition, state.NodeId, fileHandle, ref position);
            ServiceResult setPositionResult = state.SetPosition!.OnCall!(
                otherContext, state.SetPosition, state.NodeId, fileHandle, 1);
            ServiceResult closeResult = state.Close!.OnCall!(
                otherContext, state.Close, state.NodeId, fileHandle);

            Assert.Multiple(() =>
            {
                Assert.That(readResult.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(writeResult.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(getPositionResult.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(setPositionResult.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
                Assert.That(closeResult.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
            });
        }

        [Test]
        public async Task SessionClosingClosesOwnedFileHandlesAsync()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            uint fileHandle = 0;
            ServiceResult openResult = state.Open!.OnCall!(
                m_context, state.Open, state.NodeId, 0x1, ref fileHandle);
            Assert.That(ServiceResult.IsGood(openResult), Is.True);

            Mock<ISession> otherSession = CreateSession(new NodeId("other-file-session", 0));
            ISystemContext otherContext = m_manager.SystemContext.Copy(otherSession.Object);
            uint otherFileHandle = 0;
            ServiceResult otherOpenResult = state.Open.OnCall!(
                otherContext, state.Open, state.NodeId, 0x1, ref otherFileHandle);
            Assert.That(ServiceResult.IsGood(otherOpenResult), Is.True);

            var operationContext = new OperationContext(m_session.Object, DiagnosticsMasks.None);
            await m_manager.SessionClosingAsync(
                operationContext,
                m_sessionId,
                deleteSubscriptions: false).ConfigureAwait(false);

            ByteString data = default;
            ServiceResult readResult = state.Read!.OnCall!(
                m_context, state.Read, state.NodeId, fileHandle, 1, ref data);
            ServiceResult otherReadResult = state.Read.OnCall!(
                otherContext, state.Read, state.NodeId, otherFileHandle, 1, ref data);
            Variant openCount = await ReadPropertyAsync(state.OpenCount!).ConfigureAwait(false);

            Assert.That(readResult.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
            Assert.That(ServiceResult.IsGood(otherReadResult), Is.True);
            Assert.That(openCount.TryGetValue(out ushort count), Is.True);
            Assert.That(count, Is.EqualTo(1));
        }

        [Test]
        public void ReadWithShortRemainderTrimsBuffer()
        {
            FileObjectState state = CreateFileState("data.txt", "abc");

            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x1, ref fileHandle);

            ByteString data = default;
            ServiceResult readResult = state.Read!.OnCall!(
                m_context, state.Read, state.NodeId, fileHandle, 100, ref data);

            Assert.That(ServiceResult.IsGood(readResult), Is.True);
            Assert.That(data.Length, Is.EqualTo(3));
        }

        [Test]
        public void ReadWithNegativeLengthReturnsBadInvalidArgument()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x1, ref fileHandle);

            ByteString data = default;
            ServiceResult result = state.Read!.OnCall!(
                m_context, state.Read, state.NodeId, fileHandle, -1, ref data);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidArgument));
        }

        [Test]
        public void ReadWithUnknownHandleReturnsBadInvalidState()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            ByteString data = default;
            ServiceResult result = state.Read!.OnCall!(
                m_context, state.Read, state.NodeId, 999u, 4, ref data);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
        }

        [Test]
        public void OpenForWriteThenWritePersistsData()
        {
            FileObjectState state = CreateFileState("out.txt");

            uint fileHandle = 0;
            ServiceResult openResult = state.Open!.OnCall!(
                m_context, state.Open, state.NodeId, 0x2, ref fileHandle);
            Assert.That(ServiceResult.IsGood(openResult), Is.True);

            var payload = ByteString.From(Encoding.UTF8.GetBytes("written"));
            ServiceResult writeResult = state.Write!.OnCall!(
                m_context, state.Write, state.NodeId, fileHandle, payload);
            Assert.That(ServiceResult.IsGood(writeResult), Is.True);

            ServiceResult closeResult = state.Close!.OnCall!(
                m_context, state.Close, state.NodeId, fileHandle);
            Assert.That(ServiceResult.IsGood(closeResult), Is.True);

            Assert.That(File.ReadAllText(Path.Combine(m_root, "out.txt")), Is.EqualTo("written"));
        }

        [Test]
        public void WriteWithUnknownHandleReturnsBadInvalidState()
        {
            FileObjectState state = CreateFileState("out.txt");

            var payload = ByteString.From(new byte[] { 1, 2, 3 });
            ServiceResult result = state.Write!.OnCall!(
                m_context, state.Write, state.NodeId, 999u, payload);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
        }

        [Test]
        public void SetPositionAndGetPositionRoundTrip()
        {
            FileObjectState state = CreateFileState("data.txt", "0123456789");

            uint fileHandle = 0;
            state.Open!.OnCall!(m_context, state.Open, state.NodeId, 0x1, ref fileHandle);

            ServiceResult setResult = state.SetPosition!.OnCall!(
                m_context, state.SetPosition, state.NodeId, fileHandle, 3u);
            Assert.That(ServiceResult.IsGood(setResult), Is.True);

            ulong position = 0;
            ServiceResult getResult = state.GetPosition!.OnCall!(
                m_context, state.GetPosition, state.NodeId, fileHandle, ref position);
            Assert.That(ServiceResult.IsGood(getResult), Is.True);
            Assert.That(position, Is.EqualTo(3u));
        }

        [Test]
        public void SetPositionWithUnknownHandleReturnsBadInvalidState()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            ServiceResult result = state.SetPosition!.OnCall!(
                m_context, state.SetPosition, state.NodeId, 999u, 1u);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
        }

        [Test]
        public void GetPositionWithUnknownHandleReturnsBadInvalidState()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            ulong position = 0;
            ServiceResult result = state.GetPosition!.OnCall!(
                m_context, state.GetPosition, state.NodeId, 999u, ref position);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
        }

        [Test]
        public void CloseWithInvalidHandleReturnsBadInvalidState()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            ServiceResult result = state.Close!.OnCall!(
                m_context, state.Close, state.NodeId, 999u);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
        }

        [Test]
        public async Task SizePropertyReadReturnsFileLengthAsync()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            Variant value = await ReadPropertyAsync(state.Size!).ConfigureAwait(false);

            Assert.That(value.TryGetValue(out ulong size), Is.True);
            Assert.That(size, Is.EqualTo(5u));
        }

        [Test]
        public async Task WritablePropertyReadReturnsTrueForWritableProviderAsync()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            Variant value = await ReadPropertyAsync(state.Writable!).ConfigureAwait(false);

            Assert.That(value.TryGetValue(out bool writable), Is.True);
            Assert.That(writable, Is.True);
        }

        [Test]
        public async Task MimeTypePropertyReadReturnsValueAsync()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            (ServiceResult result, DataValue value) = await state.MimeType!.ReadAttributeAsync(
                m_context, Attributes.Value, NumericRange.Null, QualifiedName.Null, default).ConfigureAwait(false);

            Assert.That(result.StatusCode, Is.EqualTo(StatusCodes.Uncertain));
            Assert.That(value.StatusCode, Is.EqualTo(StatusCodes.Uncertain));
            Assert.That(value.WrappedValue.TryGetValue(out string mimeType), Is.True);
            Assert.That(mimeType, Is.EqualTo("text/plain"));
        }

        [Test]
        public async Task LastModifiedTimePropertyReadReturnsValueAsync()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            Variant value = await ReadPropertyAsync(state.LastModifiedTime!).ConfigureAwait(false);

            Assert.That(value.TryGetValue(out DateTimeUtc modified), Is.True);
            Assert.That(modified, Is.Not.Default);
        }

        [Test]
        public async Task OpenCountPropertyReadReturnsZeroWhenNotOpenAsync()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");

            Variant value = await ReadPropertyAsync(state.OpenCount!).ConfigureAwait(false);

            Assert.That(value.TryGetValue(out ushort count), Is.True);
            Assert.That(count, Is.Zero);
        }

        [Test]
        public void OpenWithUnavailableManagerReturnsBadInvalidState()
        {
            FileObjectState state = CreateFileState("data.txt", "hello");
            var orphanContext = new SystemContext(m_telemetry) { SystemHandle = null };

            uint fileHandle = 0;
            ServiceResult result = state.Open!.OnCall!(
                orphanContext, state.Open, state.NodeId, 0x1, ref fileHandle);

            Assert.That(result.StatusCode.Code, Is.EqualTo(StatusCodes.BadInvalidState));
        }

        [Test]
        public void PopulateBrowserAddsParentReferenceForNestedFile()
        {
            FileObjectState state = CreateFileState("folder/data.txt", "hello");

            using INodeBrowser browser = state.CreateBrowser(
                m_context, null, ReferenceTypeIds.HasComponent, true,
                BrowseDirection.Inverse, state.BrowseName, null, false);

            bool foundParent = false;
            for (IReference? reference = browser.Next(); reference != null; reference = browser.Next())
            {
                if (reference.ReferenceTypeId == ReferenceTypeIds.HasComponent && reference.IsInverse)
                {
                    foundParent = true;
                }
            }

            Assert.That(foundParent, Is.True);
        }

        private async ValueTask<Variant> ReadPropertyAsync(BaseVariableState variable)
        {
            (ServiceResult result, DataValue value) = await variable.ReadAttributeAsync(
                m_context, Attributes.Value, NumericRange.Null, QualifiedName.Null, default).ConfigureAwait(false);
            Assert.That(ServiceResult.IsGood(result), Is.True);
            return value.WrappedValue;
        }
    }
}