Merge branch 'main' into feat/ui-improvements

tests/ClaudeDo.Installer.Tests/ChecksumVerifierTests.cs

@@ -0,0 +1,106 @@
+using System.IO;
+using ClaudeDo.Installer.Core;
+
+namespace ClaudeDo.Installer.Tests;
+
+public sealed class ChecksumVerifierTests : IDisposable
+{
+    private readonly string _tempDir;
+
+    public ChecksumVerifierTests()
+    {
+        _tempDir = Path.Combine(Path.GetTempPath(), "ClaudeDoChecksum-" + Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(_tempDir);
+    }
+
+    public void Dispose()
+    {
+        try { Directory.Delete(_tempDir, recursive: true); } catch { }
+    }
+
+    [Fact]
+    public void ComputeSha256_KnownVector_EmptyFile()
+    {
+        var path = Path.Combine(_tempDir, "empty.bin");
+        File.WriteAllBytes(path, Array.Empty<byte>());
+
+        var hash = ChecksumVerifier.ComputeSha256(path);
+
+        Assert.Equal("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", hash);
+    }
+
+    [Fact]
+    public void ComputeSha256_KnownVector_Hello()
+    {
+        var path = Path.Combine(_tempDir, "hello.bin");
+        File.WriteAllText(path, "hello");
+
+        var hash = ChecksumVerifier.ComputeSha256(path);
+
+        Assert.Equal("2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824", hash);
+    }
+
+    [Fact]
+    public void Verify_ReturnsTrue_WhenHashMatches()
+    {
+        var path = Path.Combine(_tempDir, "x.bin");
+        File.WriteAllText(path, "hello");
+
+        Assert.True(ChecksumVerifier.Verify(path,
+            "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824"));
+    }
+
+    [Fact]
+    public void Verify_IsCaseInsensitive()
+    {
+        var path = Path.Combine(_tempDir, "x.bin");
+        File.WriteAllText(path, "hello");
+
+        Assert.True(ChecksumVerifier.Verify(path,
+            "2CF24DBA5FB0A30E26E83B2AC5B9E29E1B161E5C1FA7425E73043362938B9824"));
+    }
+
+    [Fact]
+    public void Verify_ReturnsFalse_OnMismatch()
+    {
+        var path = Path.Combine(_tempDir, "x.bin");
+        File.WriteAllText(path, "hello");
+
+        Assert.False(ChecksumVerifier.Verify(path, new string('0', 64)));
+    }
+
+    [Fact]
+    public void ParseChecksumsFile_ReadsTwoLines()
+    {
+        var content = """
+            e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855  ClaudeDo-0.2.0-win-x64.zip
+            2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824  ClaudeDo.Installer-0.2.0.exe
+            """;
+
+        var map = ChecksumVerifier.ParseChecksumsFile(content);
+
+        Assert.Equal(2, map.Count);
+        Assert.Equal(
+            "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+            map["ClaudeDo-0.2.0-win-x64.zip"]);
+        Assert.Equal(
+            "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824",
+            map["ClaudeDo.Installer-0.2.0.exe"]);
+    }
+
+    [Fact]
+    public void ParseChecksumsFile_SkipsBlankAndMalformedLines()
+    {
+        var content = """
+
+            not a line
+            e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855  file.zip
+
+            """;
+
+        var map = ChecksumVerifier.ParseChecksumsFile(content);
+
+        Assert.Single(map);
+        Assert.True(map.ContainsKey("file.zip"));
+    }
+}

tests/ClaudeDo.Installer.Tests/ClaudeDo.Installer.Tests.csproj

@@ -0,0 +1,27 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0-windows</TargetFramework>
+<ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+
+    <IsPackable>false</IsPackable>
+    <IsTestProject>true</IsTestProject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="coverlet.collector" Version="6.0.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
+    <PackageReference Include="xunit" Version="2.5.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.5.3" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Using Include="Xunit" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\ClaudeDo.Installer\ClaudeDo.Installer.csproj" />
+  </ItemGroup>
+
+</Project>

tests/ClaudeDo.Installer.Tests/DownloadAndExtractStepTests.cs

@@ -0,0 +1,148 @@
+using System.IO;
+using System.IO.Compression;
+using ClaudeDo.Installer.Core;
+using ClaudeDo.Installer.Steps;
+
+namespace ClaudeDo.Installer.Tests;
+
+public sealed class DownloadAndExtractStepTests : IDisposable
+{
+    private readonly string _tempDir;
+    private readonly string _installDir;
+
+    public DownloadAndExtractStepTests()
+    {
+        _tempDir = Path.Combine(Path.GetTempPath(), "ClaudeDoDownloadStep-" + Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(_tempDir);
+        _installDir = Path.Combine(_tempDir, "install");
+        Directory.CreateDirectory(_installDir);
+    }
+
+    public void Dispose()
+    {
+        try { Directory.Delete(_tempDir, recursive: true); } catch { }
+    }
+
+    private sealed class FileCopyReleaseClient : IReleaseClient
+    {
+        private readonly Dictionary<string, string> _urlToSourceFile;
+        public GiteaRelease? Release { get; set; }
+
+        public FileCopyReleaseClient(Dictionary<string, string> urlToSourceFile)
+            => _urlToSourceFile = urlToSourceFile;
+
+        public Task<GiteaRelease?> GetLatestReleaseAsync(CancellationToken ct) => Task.FromResult(Release);
+
+        public Task DownloadAsync(string url, string destPath, IProgress<long> progress, CancellationToken ct)
+        {
+            File.Copy(_urlToSourceFile[url], destPath, overwrite: true);
+            progress.Report(new FileInfo(destPath).Length);
+            return Task.CompletedTask;
+        }
+    }
+
+    [Fact]
+    public async Task Extracts_Zip_Into_InstallDir_App_And_Worker()
+    {
+        var zipPath = Path.Combine(_tempDir, "release.zip");
+        using (var fs = File.Create(zipPath))
+        using (var zip = new ZipArchive(fs, ZipArchiveMode.Create))
+        {
+            var a = zip.CreateEntry("app/a.txt");
+            using (var w = new StreamWriter(a.Open())) w.Write("hello-app");
+            var b = zip.CreateEntry("worker/b.txt");
+            using (var w = new StreamWriter(b.Open())) w.Write("hello-worker");
+        }
+
+        var zipHash = ChecksumVerifier.ComputeSha256(zipPath);
+        var checksumsPath = Path.Combine(_tempDir, "checksums.txt");
+        File.WriteAllText(checksumsPath, $"{zipHash}  ClaudeDo-0.1.0-win-x64.zip\n");
+
+        var release = new GiteaRelease("v0.1.0", "v0.1.0", new[]
+        {
+            new ReleaseAsset("ClaudeDo-0.1.0-win-x64.zip", "fake://zip", new FileInfo(zipPath).Length),
+            new ReleaseAsset("checksums.txt", "fake://checksums", new FileInfo(checksumsPath).Length),
+        });
+
+        var client = new FileCopyReleaseClient(new()
+        {
+            ["fake://zip"] = zipPath,
+            ["fake://checksums"] = checksumsPath,
+        }) { Release = release };
+
+        var step = new DownloadAndExtractStep(client);
+        var ctx = new InstallContext { InstallDirectory = _installDir };
+
+        var result = await step.ExecuteAsync(ctx, new Progress<string>(_ => { }), CancellationToken.None);
+
+        Assert.True(result.Success, result.ErrorMessage);
+        Assert.Equal("hello-app", File.ReadAllText(Path.Combine(_installDir, "app", "a.txt")));
+        Assert.Equal("hello-worker", File.ReadAllText(Path.Combine(_installDir, "worker", "b.txt")));
+        Assert.Equal("0.1.0", ctx.InstalledVersion);
+    }
+
+    [Fact]
+    public async Task Fails_On_ChecksumMismatch_Without_Overwriting_InstallDir()
+    {
+        var zipPath = Path.Combine(_tempDir, "release.zip");
+        using (var fs = File.Create(zipPath))
+        using (var zip = new ZipArchive(fs, ZipArchiveMode.Create))
+        {
+            var a = zip.CreateEntry("app/a.txt");
+            using (var w = new StreamWriter(a.Open())) w.Write("x");
+        }
+
+        var checksumsPath = Path.Combine(_tempDir, "checksums.txt");
+        File.WriteAllText(checksumsPath, $"{new string('0', 64)}  ClaudeDo-0.1.0-win-x64.zip\n");
+
+        File.WriteAllText(Path.Combine(_installDir, "marker.txt"), "untouched");
+
+        var release = new GiteaRelease("v0.1.0", "v0.1.0", new[]
+        {
+            new ReleaseAsset("ClaudeDo-0.1.0-win-x64.zip", "fake://zip", 0),
+            new ReleaseAsset("checksums.txt", "fake://checksums", 0),
+        });
+
+        var client = new FileCopyReleaseClient(new()
+        {
+            ["fake://zip"] = zipPath,
+            ["fake://checksums"] = checksumsPath,
+        }) { Release = release };
+
+        var step = new DownloadAndExtractStep(client);
+        var ctx = new InstallContext { InstallDirectory = _installDir };
+
+        var result = await step.ExecuteAsync(ctx, new Progress<string>(_ => { }), CancellationToken.None);
+
+        Assert.False(result.Success);
+        Assert.Contains("checksum", result.ErrorMessage!, StringComparison.OrdinalIgnoreCase);
+        Assert.True(File.Exists(Path.Combine(_installDir, "marker.txt")));
+        Assert.False(Directory.Exists(Path.Combine(_installDir, "app")));
+    }
+
+    [Fact]
+    public async Task Fails_When_Release_Has_No_Zip_Asset()
+    {
+        var release = new GiteaRelease("v0.1.0", "v0.1.0", Array.Empty<ReleaseAsset>());
+        var client = new FileCopyReleaseClient(new()) { Release = release };
+        var step = new DownloadAndExtractStep(client);
+        var ctx = new InstallContext { InstallDirectory = _installDir };
+
+        var result = await step.ExecuteAsync(ctx, new Progress<string>(_ => { }), CancellationToken.None);
+
+        Assert.False(result.Success);
+        Assert.Contains("not found", result.ErrorMessage!, StringComparison.OrdinalIgnoreCase);
+    }
+
+    [Fact]
+    public async Task Fails_When_ReleaseClient_Returns_Null()
+    {
+        var client = new FileCopyReleaseClient(new()) { Release = null };
+        var step = new DownloadAndExtractStep(client);
+        var ctx = new InstallContext { InstallDirectory = _installDir };
+
+        var result = await step.ExecuteAsync(ctx, new Progress<string>(_ => { }), CancellationToken.None);
+
+        Assert.False(result.Success);
+    }
+}

tests/ClaudeDo.Installer.Tests/FakeHttpMessageHandler.cs

@@ -0,0 +1,32 @@
+using System.Net;
+using System.Net.Http;
+
+namespace ClaudeDo.Installer.Tests;
+
+internal sealed class FakeHttpMessageHandler : HttpMessageHandler
+{
+    private readonly Func<HttpRequestMessage, HttpResponseMessage> _handler;
+    private readonly object _lock = new();
+    private readonly List<HttpRequestMessage> _requests = new();
+
+    public FakeHttpMessageHandler(Func<HttpRequestMessage, HttpResponseMessage> handler)
+    {
+        _handler = handler;
+    }
+
+    public FakeHttpMessageHandler(HttpStatusCode status, string body)
+        : this(_ => new HttpResponseMessage(status) { Content = new StringContent(body) })
+    {
+    }
+
+    public IReadOnlyList<HttpRequestMessage> Requests
+    {
+        get { lock (_lock) return _requests.ToArray(); }
+    }
+
+    protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+    {
+        lock (_lock) _requests.Add(request);
+        return Task.FromResult(_handler(request));
+    }
+}

tests/ClaudeDo.Installer.Tests/InstallManifestStoreTests.cs

@@ -0,0 +1,76 @@
+using System.IO;
+using ClaudeDo.Installer.Core;
+
+namespace ClaudeDo.Installer.Tests;
+
+public sealed class InstallManifestStoreTests : IDisposable
+{
+    private readonly string _tempDir;
+
+    public InstallManifestStoreTests()
+    {
+        _tempDir = Path.Combine(Path.GetTempPath(), "ClaudeDoInstallerTests-" + Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(_tempDir);
+    }
+
+    public void Dispose()
+    {
+        try { Directory.Delete(_tempDir, recursive: true); } catch { /* best effort */ }
+    }
+
+    [Fact]
+    public void TryRead_ReturnsNull_WhenFileMissing()
+    {
+        var result = InstallManifestStore.TryRead(_tempDir);
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void Write_Then_Read_RoundTripsAllFields()
+    {
+        var manifest = new InstallManifest(
+            Version: "0.2.0",
+            InstallDir: _tempDir,
+            WorkerDir: Path.Combine(_tempDir, "worker"),
+            InstalledAt: new DateTimeOffset(2026, 4, 15, 12, 34, 56, TimeSpan.Zero));
+
+        InstallManifestStore.Write(_tempDir, manifest);
+
+        var round = InstallManifestStore.TryRead(_tempDir);
+        Assert.NotNull(round);
+        Assert.Equal("0.2.0", round!.Version);
+        Assert.Equal(manifest.InstallDir, round.InstallDir);
+        Assert.Equal(manifest.WorkerDir, round.WorkerDir);
+        Assert.Equal(manifest.InstalledAt, round.InstalledAt);
+    }
+
+    [Fact]
+    public void Write_CreatesInstallDir_IfMissing()
+    {
+        var nested = Path.Combine(_tempDir, "nested");
+        Assert.False(Directory.Exists(nested));
+
+        InstallManifestStore.Write(nested, new InstallManifest(
+            "0.0.1", nested, Path.Combine(nested, "worker"), DateTimeOffset.UtcNow));
+
+        Assert.True(File.Exists(Path.Combine(nested, "install.json")));
+    }
+
+    [Fact]
+    public void TryRead_ReturnsNull_WhenJsonMalformed()
+    {
+        File.WriteAllText(Path.Combine(_tempDir, "install.json"), "{ not json");
+        var result = InstallManifestStore.TryRead(_tempDir);
+        Assert.Null(result);
+    }
+
+    [Fact]
+    public void TryRead_ReturnsNull_WhenJsonIsValidButShapeIsWrong()
+    {
+        // Valid JSON, but installedAt has a wrong type — causes JsonException, swallowed silently.
+        File.WriteAllText(Path.Combine(_tempDir, "install.json"),
+            """{"version":"1.0","installDir":"x","workerDir":"y","installedAt":12345}""");
+        var result = InstallManifestStore.TryRead(_tempDir);
+        Assert.Null(result);
+    }
+}

tests/ClaudeDo.Installer.Tests/InstallModeDetectorTests.cs

@@ -0,0 +1,124 @@
+using ClaudeDo.Installer.Core;
+
+namespace ClaudeDo.Installer.Tests;
+
+public sealed class InstallModeDetectorTests : IDisposable
+{
+    private readonly string _tempDir;
+
+    public InstallModeDetectorTests()
+    {
+        _tempDir = Path.Combine(Path.GetTempPath(), "ClaudeDoDetector-" + Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(_tempDir);
+    }
+
+    public void Dispose()
+    {
+        try { Directory.Delete(_tempDir, recursive: true); } catch { }
+    }
+
+    private sealed class FakeReleaseClient : IReleaseClient
+    {
+        public GiteaRelease? Release { get; set; }
+        public Task<GiteaRelease?> GetLatestReleaseAsync(CancellationToken ct) => Task.FromResult(Release);
+        public Task DownloadAsync(string url, string destPath, IProgress<long> progress, CancellationToken ct)
+            => throw new NotSupportedException();
+    }
+
+    [Fact]
+    public async Task Detect_FreshInstall_WhenManifestMissing()
+    {
+        var detector = new InstallModeDetector(new FakeReleaseClient());
+
+        var state = await detector.DetectAsync(_tempDir, CancellationToken.None);
+
+        Assert.Equal(InstallerMode.FreshInstall, state.Mode);
+        Assert.Null(state.Existing);
+    }
+
+    [Fact]
+    public async Task Detect_Config_WhenManifestPresent_And_Api_Unreachable()
+    {
+        InstallManifestStore.Write(_tempDir,
+            new InstallManifest("0.1.0", _tempDir, _tempDir, DateTimeOffset.UtcNow));
+
+        var detector = new InstallModeDetector(new FakeReleaseClient { Release = null });
+
+        var state = await detector.DetectAsync(_tempDir, CancellationToken.None);
+
+        Assert.Equal(InstallerMode.Config, state.Mode);
+        Assert.Equal("0.1.0", state.Existing!.Version);
+    }
+
+    [Fact]
+    public async Task Detect_Update_WhenLatest_GreaterThan_Installed()
+    {
+        InstallManifestStore.Write(_tempDir,
+            new InstallManifest("0.1.0", _tempDir, _tempDir, DateTimeOffset.UtcNow));
+
+        var fake = new FakeReleaseClient
+        {
+            Release = new GiteaRelease("v0.2.0", "v0.2.0", Array.Empty<ReleaseAsset>())
+        };
+        var detector = new InstallModeDetector(fake);
+
+        var state = await detector.DetectAsync(_tempDir, CancellationToken.None);
+
+        Assert.Equal(InstallerMode.Update, state.Mode);
+        Assert.Equal("0.1.0", state.Existing!.Version);
+        Assert.Equal("0.2.0", state.LatestVersion);
+    }
+
+    [Fact]
+    public async Task Detect_Config_WhenLatest_EqualsOrOlderThan_Installed()
+    {
+        InstallManifestStore.Write(_tempDir,
+            new InstallManifest("0.2.0", _tempDir, _tempDir, DateTimeOffset.UtcNow));
+
+        var fake = new FakeReleaseClient
+        {
+            Release = new GiteaRelease("v0.2.0", "v0.2.0", Array.Empty<ReleaseAsset>())
+        };
+        var detector = new InstallModeDetector(fake);
+
+        var state = await detector.DetectAsync(_tempDir, CancellationToken.None);
+
+        Assert.Equal(InstallerMode.Config, state.Mode);
+    }
+
+    [Fact]
+    public async Task Detect_Config_WhenInstalledIs_Newer_Than_Latest()
+    {
+        InstallManifestStore.Write(_tempDir,
+            new InstallManifest("0.3.0", _tempDir, _tempDir, DateTimeOffset.UtcNow));
+
+        var fake = new FakeReleaseClient
+        {
+            Release = new GiteaRelease("v0.2.0", "v0.2.0", Array.Empty<ReleaseAsset>())
+        };
+        var detector = new InstallModeDetector(fake);
+
+        var state = await detector.DetectAsync(_tempDir, CancellationToken.None);
+
+        Assert.Equal(InstallerMode.Config, state.Mode);
+    }
+
+    [Fact]
+    public async Task Detect_Config_WhenInstalledVersion_IsUnparseable()
+    {
+        // install.json has been tampered with or written by an older installer with a
+        // version string we can't compare. Must not crash; must land on Config (no update).
+        InstallManifestStore.Write(_tempDir,
+            new InstallManifest("garbage", _tempDir, _tempDir, DateTimeOffset.UtcNow));
+
+        var fake = new FakeReleaseClient
+        {
+            Release = new GiteaRelease("v0.2.0", "v0.2.0", Array.Empty<ReleaseAsset>())
+        };
+        var detector = new InstallModeDetector(fake);
+
+        var state = await detector.DetectAsync(_tempDir, CancellationToken.None);
+
+        Assert.Equal(InstallerMode.Config, state.Mode);
+    }
+}

tests/ClaudeDo.Installer.Tests/ReleaseClientTests.cs

@@ -0,0 +1,109 @@
+using System.Net;
+using System.Net.Http;
+using ClaudeDo.Installer.Core;
+
+namespace ClaudeDo.Installer.Tests;
+
+public sealed class ReleaseClientTests
+{
+    private const string ApiBase = "https://git.example.test/api/v1/repos/releases/ClaudeDo";
+
+    [Fact]
+    public async Task GetLatestReleaseAsync_ParsesTagAndAssets()
+    {
+        const string json = """
+            {
+              "tag_name": "v0.2.0",
+              "name": "v0.2.0",
+              "assets": [
+                {
+                  "name": "ClaudeDo-0.2.0-win-x64.zip",
+                  "browser_download_url": "https://git.example.test/dl/zip",
+                  "size": 12345
+                },
+                {
+                  "name": "checksums.txt",
+                  "browser_download_url": "https://git.example.test/dl/checksums",
+                  "size": 128
+                }
+              ]
+            }
+            """;
+
+        var handler = new FakeHttpMessageHandler(HttpStatusCode.OK, json);
+        using var http = new HttpClient(handler);
+        var client = new ReleaseClient(http, ApiBase);
+
+        var release = await client.GetLatestReleaseAsync(CancellationToken.None);
+
+        Assert.NotNull(release);
+        Assert.Equal("v0.2.0", release!.TagName);
+        Assert.Equal(2, release.Assets.Count);
+        Assert.Equal("ClaudeDo-0.2.0-win-x64.zip", release.Assets[0].Name);
+        Assert.Equal("https://git.example.test/dl/zip", release.Assets[0].BrowserDownloadUrl);
+        Assert.Equal(12345, release.Assets[0].Size);
+    }
+
+    [Fact]
+    public async Task GetLatestReleaseAsync_Returns_Null_On404()
+    {
+        var handler = new FakeHttpMessageHandler(HttpStatusCode.NotFound, "");
+        using var http = new HttpClient(handler);
+        var client = new ReleaseClient(http, ApiBase);
+
+        var release = await client.GetLatestReleaseAsync(CancellationToken.None);
+
+        Assert.Null(release);
+    }
+
+    [Fact]
+    public async Task GetLatestReleaseAsync_Returns_Null_OnNetworkError()
+    {
+        var handler = new FakeHttpMessageHandler(_ => throw new HttpRequestException("boom"));
+        using var http = new HttpClient(handler);
+        var client = new ReleaseClient(http, ApiBase);
+
+        var release = await client.GetLatestReleaseAsync(CancellationToken.None);
+
+        Assert.Null(release);
+    }
+
+    [Fact]
+    public async Task GetLatestReleaseAsync_Hits_CorrectUrl()
+    {
+        var handler = new FakeHttpMessageHandler(HttpStatusCode.OK, "{\"tag_name\":\"v0.1.0\",\"assets\":[]}");
+        using var http = new HttpClient(handler);
+        var client = new ReleaseClient(http, ApiBase);
+
+        _ = await client.GetLatestReleaseAsync(CancellationToken.None);
+
+        Assert.Single(handler.Requests);
+        Assert.Equal($"{ApiBase}/releases/latest", handler.Requests[0].RequestUri!.ToString());
+    }
+
+    [Fact]
+    public async Task DownloadAsync_WritesBytesToDisk()
+    {
+        var payload = new byte[] { 1, 2, 3, 4, 5 };
+        var handler = new FakeHttpMessageHandler(_ => new HttpResponseMessage(HttpStatusCode.OK)
+        {
+            Content = new ByteArrayContent(payload)
+        });
+        using var http = new HttpClient(handler);
+        var client = new ReleaseClient(http, ApiBase);
+
+        var tempPath = Path.Combine(Path.GetTempPath(), "ClaudeDoDlTest-" + Guid.NewGuid().ToString("N"));
+        try
+        {
+            await client.DownloadAsync("https://example/foo", tempPath,
+                new Progress<long>(_ => { }), CancellationToken.None);
+
+            Assert.True(File.Exists(tempPath));
+            Assert.Equal(payload, File.ReadAllBytes(tempPath));
+        }
+        finally
+        {
+            if (File.Exists(tempPath)) File.Delete(tempPath);
+        }
+    }
+}

tests/ClaudeDo.Installer.Tests/WriteInstallManifestStepTests.cs

@@ -0,0 +1,51 @@
+using ClaudeDo.Installer.Core;
+using ClaudeDo.Installer.Steps;
+
+namespace ClaudeDo.Installer.Tests;
+
+public sealed class WriteInstallManifestStepTests : IDisposable
+{
+    private readonly string _installDir;
+
+    public WriteInstallManifestStepTests()
+    {
+        _installDir = Path.Combine(Path.GetTempPath(), "ClaudeDoWriteManifest-" + Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(_installDir);
+    }
+
+    public void Dispose()
+    {
+        try { Directory.Delete(_installDir, recursive: true); } catch { }
+    }
+
+    [Fact]
+    public async Task Writes_Manifest_WithAllFields()
+    {
+        var ctx = new InstallContext
+        {
+            InstallDirectory = _installDir,
+            InstalledVersion = "0.2.0",
+        };
+
+        var step = new WriteInstallManifestStep();
+        var result = await step.ExecuteAsync(ctx, new Progress<string>(_ => { }), CancellationToken.None);
+
+        Assert.True(result.Success);
+        var manifest = InstallManifestStore.TryRead(_installDir);
+        Assert.NotNull(manifest);
+        Assert.Equal("0.2.0", manifest!.Version);
+        Assert.Equal(_installDir, manifest.InstallDir);
+        Assert.Equal(Path.Combine(_installDir, "worker"), manifest.WorkerDir);
+    }
+
+    [Fact]
+    public async Task Fails_When_InstalledVersion_Missing()
+    {
+        var ctx = new InstallContext { InstallDirectory = _installDir };  // no version set
+
+        var step = new WriteInstallManifestStep();
+        var result = await step.ExecuteAsync(ctx, new Progress<string>(_ => { }), CancellationToken.None);
+
+        Assert.False(result.Success);
+    }
+}