test: xUnit test suite and Forgejo CI pipeline

- 43 tests across SlugGuard, ReplContext navigation, NotesCache.TimeAgo
- SlugGuard moved to NozCli.Core.Security (shared between REPL and tests)
- Bug fix: FoldersInView() now returns only actual sub-folders, not note segments
  (previously cd tab-completion suggested note names as navigable folders)
- .forgejo/workflows/ci.yml: build + test on every push/PR

.forgejo/workflows/ci.yml

@@ -0,0 +1,27 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup .NET 10
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: '10.x'
+
+      - name: Restore
+        run: dotnet restore
+
+      - name: Build
+        run: dotnet build --no-restore -c Release
+
+      - name: Test
+        run: dotnet test NozCli.Tests/NozCli.Tests.csproj --no-build -c Release --verbosity normal

NozCli.Core/Security/SlugGuard.cs

@@ -0,0 +1,34 @@
+using System.Text.RegularExpressions;
+
+namespace NozCli.Core.Security;
+
+/// Validates slugs before they are sent to the server or written to disk.
+public static partial class SlugGuard
+{
+    // Valid slug: lowercase alphanumeric + hyphens, optionally separated by /
+    // Examples: "hydroponik", "biosysteme/hydroponik", "a/b/c"
+    [GeneratedRegex(@"^[a-z0-9][a-z0-9\-]*(?:/[a-z0-9][a-z0-9\-]*)*$")]
+    private static partial Regex ValidSlugRegex();
+
+    /// Returns true if the slug is safe to use (no path traversal, valid chars).
+    public static bool IsValid(string slug) =>
+        !string.IsNullOrWhiteSpace(slug) &&
+        !slug.Contains("..") &&
+        !slug.Contains("//") &&
+        ValidSlugRegex().IsMatch(slug);
+
+    /// Resolves a slug to a file path inside baseDir.
+    /// Returns null if the resulting path would escape baseDir (path traversal).
+    public static string? ToSafePath(string baseDir, string slug, string extension = ".md")
+    {
+        var rel      = slug.Replace('/', Path.DirectorySeparatorChar) + extension;
+        var fullPath = Path.GetFullPath(Path.Combine(baseDir, rel));
+        var baseFull = Path.GetFullPath(baseDir);
+
+        // Ensure the resolved path stays strictly inside baseDir
+        return fullPath.StartsWith(baseFull + Path.DirectorySeparatorChar,
+            StringComparison.OrdinalIgnoreCase)
+            ? fullPath
+            : null;
+    }
+}

NozCli.Tests/NotesCacheTests.cs

@@ -0,0 +1,23 @@
+using Xunit;
+using NozCli.Repl;
+
+namespace NozCli.Tests;
+
+public class NotesCacheTests
+{
+    [Theory]
+    [InlineData(10,    "gerade eben")]
+    [InlineData(59,    "gerade eben")]
+    [InlineData(60,    "vor 1 Min.")]
+    [InlineData(300,   "vor 5 Min.")]
+    [InlineData(3599,  "vor 59 Min.")]
+    [InlineData(3600,  "vor 1 Std.")]
+    [InlineData(7200,  "vor 2 Std.")]
+    [InlineData(86400, "vor 1 Tagen")]
+    public void TimeAgo_ReturnsCorrectLabel(int secondsAgo, string expected)
+    {
+        var dt     = DateTimeOffset.UtcNow.AddSeconds(-secondsAgo);
+        var result = NotesCache.TimeAgo(dt);
+        Assert.Equal(expected, result);
+    }
+}

NozCli.Tests/NozCli.Tests.csproj

@@ -0,0 +1,26 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <ItemGroup>
+    <ProjectReference Include="..\NozCli.Core\NozCli.Core.csproj" />
+    <ProjectReference Include="..\NozCli\NozCli.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2">
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+      <PrivateAssets>all</PrivateAssets>
+    </PackageReference>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <IsPackable>false</IsPackable>
+    <!-- Disable AOT for the test project even though NozCli has PublishAot=true -->
+    <PublishAot>false</PublishAot>
+  </PropertyGroup>
+
+</Project>

NozCli.Tests/ReplContextTests.cs

@@ -0,0 +1,165 @@
+using Xunit;
+using NozCli.Core.Config;
+using NozCli.Core.Models;
+using NozCli.Repl;
+
+namespace NozCli.Tests;
+
+public class ReplContextTests
+{
+    // Builds a ReplContext with a fixed NoteCache — no API calls made.
+    private static ReplContext BuildCtx(params NoteInfo[] notes)
+    {
+        var cfg = new LocalConfig { ServerUrl = "http://localhost:9999", Token = "test" };
+        var ctx = new ReplContext(null!, cfg);   // Api is null — not used in navigation
+        ctx.NoteCache = [.. notes];
+        return ctx;
+    }
+
+    private static NoteInfo Note(string slug, string topic, string status = "seed") =>
+        new(slug, $"Title {slug}", status, topic, "de", false, null);
+
+    // ── CurrentPath ──────────────────────────────────────────────────────────
+
+    [Fact]
+    public void CurrentPath_AtRoot_IsWave()
+    {
+        var ctx = BuildCtx();
+        Assert.Equal("~", ctx.CurrentPath);
+    }
+
+    [Fact]
+    public void CurrentPath_InTopic_ShowsTopic()
+    {
+        var ctx = BuildCtx(Note("psychologie/test", "psychologie"));
+        ctx.NavigateTo("psychologie");
+        Assert.Equal("~/psychologie", ctx.CurrentPath);
+    }
+
+    [Fact]
+    public void CurrentPath_InSubfolder_ShowsFullPath()
+    {
+        var ctx = BuildCtx(Note("psychologie/sub/deep", "psychologie"));
+        ctx.NavigateTo("psychologie");
+        ctx.NavigateTo("sub");
+        Assert.Equal("~/psychologie/sub", ctx.CurrentPath);
+    }
+
+    // ── FoldersInView ────────────────────────────────────────────────────────
+
+    [Fact]
+    public void FoldersInView_AtRoot_ReturnsDistinctTopics()
+    {
+        var ctx = BuildCtx(
+            Note("psychologie/a", "psychologie"),
+            Note("psychologie/b", "psychologie"),
+            Note("biosysteme/c",  "biosysteme"));
+
+        var folders = ctx.FoldersInView().OrderBy(f => f).ToList();
+        Assert.Equal(["biosysteme", "psychologie"], folders);
+    }
+
+    [Fact]
+    public void FoldersInView_InTopic_ReturnsSubfolders()
+    {
+        var ctx = BuildCtx(
+            Note("psychologie/sub/note",  "psychologie"),
+            Note("psychologie/flat-note", "psychologie"));
+
+        ctx.NavigateTo("psychologie");
+        var folders = ctx.FoldersInView().ToList();
+
+        Assert.Contains("sub", folders);
+        Assert.DoesNotContain("flat-note", folders);
+    }
+
+    // ── NavigateTo / NavigateUp ──────────────────────────────────────────────
+
+    [Fact]
+    public void NavigateTo_ValidTopic_ReturnsTrue()
+    {
+        var ctx = BuildCtx(Note("psychologie/test", "psychologie"));
+        Assert.True(ctx.NavigateTo("psychologie"));
+        Assert.Equal("psychologie", ctx.CurrentTopic);
+    }
+
+    [Fact]
+    public void NavigateTo_UnknownTopic_ReturnsFalse()
+    {
+        var ctx = BuildCtx(Note("psychologie/test", "psychologie"));
+        Assert.False(ctx.NavigateTo("doesnotexist"));
+        Assert.Null(ctx.CurrentTopic);
+    }
+
+    [Fact]
+    public void NavigateUp_FromTopic_ReturnsToRoot()
+    {
+        var ctx = BuildCtx(Note("psychologie/test", "psychologie"));
+        ctx.NavigateTo("psychologie");
+        ctx.NavigateUp();
+        Assert.Null(ctx.CurrentTopic);
+        Assert.Equal("~", ctx.CurrentPath);
+    }
+
+    [Fact]
+    public void NavigateUp_FromSubfolder_ReturnsToTopic()
+    {
+        var ctx = BuildCtx(Note("psychologie/sub/deep", "psychologie"));
+        ctx.NavigateTo("psychologie");
+        ctx.NavigateTo("sub");
+        ctx.NavigateUp();
+
+        Assert.Equal("psychologie", ctx.CurrentTopic);
+        Assert.Null(ctx.CurrentSubPath);
+    }
+
+    // ── SlugRelative ─────────────────────────────────────────────────────────
+
+    [Fact]
+    public void SlugRelative_InTopic_StripsTopicPrefix()
+    {
+        var ctx = BuildCtx(Note("psychologie/flow", "psychologie"));
+        ctx.NavigateTo("psychologie");
+        Assert.Equal("flow", ctx.SlugRelative("psychologie/flow"));
+    }
+
+    [Fact]
+    public void SlugRelative_AtRoot_ReturnsFullSlug()
+    {
+        var ctx = BuildCtx(Note("psychologie/flow", "psychologie"));
+        Assert.Equal("psychologie/flow", ctx.SlugRelative("psychologie/flow"));
+    }
+
+    // ── NotesInView ──────────────────────────────────────────────────────────
+
+    [Fact]
+    public void NotesInView_InTopic_FiltersCorrectly()
+    {
+        var ctx = BuildCtx(
+            Note("psychologie/a", "psychologie"),
+            Note("biosysteme/b",  "biosysteme"));
+
+        ctx.NavigateTo("psychologie");
+        var notes = ctx.NotesInView().ToList();
+
+        Assert.Single(notes);
+        Assert.Equal("psychologie/a", notes[0].Slug);
+    }
+
+    // ── ResolveSlug ──────────────────────────────────────────────────────────
+
+    [Fact]
+    public void ResolveSlug_ShortName_InTopic_ResolvesToFullSlug()
+    {
+        var ctx = BuildCtx(Note("psychologie/flow", "psychologie"));
+        ctx.NavigateTo("psychologie");
+        Assert.Equal("psychologie/flow", ctx.ResolveSlug("flow"));
+    }
+
+    [Fact]
+    public void ResolveSlug_AlreadyFullSlug_ReturnsUnchanged()
+    {
+        var ctx = BuildCtx(Note("psychologie/flow", "psychologie"));
+        Assert.Equal("psychologie/flow", ctx.ResolveSlug("psychologie/flow"));
+    }
+}

NozCli.Tests/SlugGuardTests.cs

@@ -0,0 +1,68 @@
+using Xunit;
+using NozCli.Core.Security;
+
+namespace NozCli.Tests;
+
+public class SlugGuardTests
+{
+    // ── IsValid ──────────────────────────────────────────────────────────────
+
+    [Theory]
+    [InlineData("simple-note",              true)]
+    [InlineData("psychologie/test",         true)]
+    [InlineData("biosysteme/sub/deep",      true)]
+    [InlineData("note123",                  true)]
+    [InlineData("a",                        true)]
+    public void IsValid_AcceptsValidSlugs(string slug, bool expected)
+        => Assert.Equal(expected, SlugGuard.IsValid(slug));
+
+    [Theory]
+    [InlineData("../../etc/passwd",         false)] // path traversal
+    [InlineData("../escape",                false)] // path traversal
+    [InlineData("note/../other",            false)] // embedded traversal
+    [InlineData("UPPERCASE",               false)] // uppercase not allowed
+    [InlineData("has space",               false)] // spaces not allowed
+    [InlineData("",                         false)] // empty
+    [InlineData("   ",                      false)] // whitespace
+    [InlineData("note//double",            false)] // double slash
+    [InlineData("/leading-slash",          false)] // leading slash
+    [InlineData("trailing/",               false)] // trailing slash
+    [InlineData("Sonderzeichen!",          false)] // special chars
+    public void IsValid_RejectsInvalidSlugs(string slug, bool expected)
+        => Assert.Equal(expected, SlugGuard.IsValid(slug));
+
+    // ── ToSafePath ───────────────────────────────────────────────────────────
+
+    [Fact]
+    public void ToSafePath_ValidSlug_ReturnsPathInsideBase()
+    {
+        var baseDir = Path.Combine(Path.GetTempPath(), "noz-test");
+        var result  = SlugGuard.ToSafePath(baseDir, "psychologie/test");
+
+        Assert.NotNull(result);
+        Assert.StartsWith(baseDir, result);
+        Assert.EndsWith(".md", result);
+        Assert.Contains("psychologie", result);
+    }
+
+    [Theory]
+    [InlineData("../../etc/passwd")]
+    [InlineData("../escape")]
+    [InlineData("sub/../../outside")]
+    public void ToSafePath_TraversalSlug_ReturnsNull(string slug)
+    {
+        var baseDir = Path.Combine(Path.GetTempPath(), "noz-test");
+        Assert.Null(SlugGuard.ToSafePath(baseDir, slug));
+    }
+
+    [Fact]
+    public void ToSafePath_NestedSlug_BuildsCorrectPath()
+    {
+        var baseDir = "/tmp/vault";
+        var result  = SlugGuard.ToSafePath(baseDir, "a/b/c");
+
+        Assert.NotNull(result);
+        var expected = Path.Combine("/tmp/vault", "a", "b", "c") + ".md";
+        Assert.Equal(expected, result);
+    }
+}

NozCli/Commands/PushCommand.cs

@@ -1,5 +1,5 @@
 using NozCli.Repl;
-using NozCli.Security;
+using NozCli.Core.Security;
 using Spectre.Console;
 
 namespace NozCli.Commands;

NozCli/Commands/SyncCommand.cs

@@ -1,7 +1,7 @@
 using NozCli.Core.Client;
 using NozCli.Core.Models;
 using NozCli.Repl;
-using NozCli.Security;
+using NozCli.Core.Security;
 using Spectre.Console;
 
 namespace NozCli.Commands;

NozCli/Repl/ReplContext.cs

@@ -70,6 +70,7 @@ public class ReplContext
 
         var depth = CurrentSubPath is null ? 0 : CurrentSubPath.Split('/').Length;
         return NotesInView()
+            .Where(n => SlugRelative(n.Slug).Split('/').Length > depth + 1)
             .Select(n => SlugRelative(n.Slug).Split('/').ElementAtOrDefault(depth))
             .Where(s => s is not null)
             .Distinct(StringComparer.OrdinalIgnoreCase)!;

noz-cli.slnx

@@ -2,4 +2,5 @@
   <Project Path="NozCli.Core/NozCli.Core.csproj" />
   <Project Path="NozCli/NozCli.csproj" />
   <Project Path="Noz.PowerShell/Noz.PowerShell.csproj" />
+  <Project Path="NozCli.Tests/NozCli.Tests.csproj" />
 </Solution>