diff --git a/ViewModels/MainViewModel.cs b/ViewModels/MainViewModel.cs
index d4be41d..59b5ced 100644
--- a/ViewModels/MainViewModel.cs
+++ b/ViewModels/MainViewModel.cs
@@ -481,7 +481,7 @@ public class MainViewModel : ViewModelBase
SaveLayoutAsCommand = new RelayCommand(_ => SaveLayoutAs());
OpenLayoutCommand = new RelayCommand(_ => OpenLayoutFile());
- _layoutStore = new LayoutStore(DefaultLayoutPath);
+ _layoutStore = new LayoutStore(LayoutPathOverride ?? DefaultLayoutPath);
_activeLayoutPath = _layoutStore.ActivePath;
_cameraEnumerator = new MediaCaptureCameraEnumerator();
@@ -531,6 +531,11 @@ public class MainViewModel : ViewModelBase
"ytLlive",
"ytLlive.db");
+ // Test seam: a real MainWindow test must never read or write the user's
+ // real layout DB (it would persist test sources over real ones). Tests set
+ // this to a temp path before constructing MainWindow and reset it after.
+ internal static string? LayoutPathOverride { get; set; }
+
private void LoadLayout()
{
_isLoading = true;
diff --git a/ai.md b/ai.md
index be70fe6..f9afcde 100644
--- a/ai.md
+++ b/ai.md
@@ -45,7 +45,25 @@ dotnet.exe vstest "C:\...\ytLive.Tests\bin\Debug\net8.0-windows10.0.19041.0\ytLi
Good Dog Rule: ONE integration test per branch, ONE test per PR. Current: TokenStore DPAPI
roundtrip/corrupt/missing/clear, OAuth exchange/refresh/ClearSession, CameraManager refcount +
-frame pump + failure handling (fakes for the WinRT seams) — 11 passing.
+frame pump + failure handling (fakes for the WinRT seams), real-`MainWindow` round-clip
+interaction test, LayoutStore delete roundtrip — 13 passing.
+
+### Real-MainWindow tests MUST be hermetic (DB pollution bug)
+
+The integration test boots a real `MainWindow` → `MainViewModel` → real `LayoutStore`
+(`%APPDATA%\ytLlive\ytLlive.db`). `Shutdown()` on close **saves the layout** (full rewrite:
+DELETE all scenes/sources, re-insert), so any source a test adds would be persisted over the
+user's real ones — this happened and wiped the real webcam source (DeviceId replaced by the
+test's fake `test-camera`). Rule: a test that constructs `MainWindow` MUST first set
+`MainViewModel.LayoutPathOverride` to a temp DB path and reset it (plus
+`SqliteConnection.ClearAllPools()` + delete) in `finally`. The seam is
+`internal static string? LayoutPathOverride` (line ~529 in `MainViewModel.cs`),
+`ytLive.csproj` has `InternalsVisibleTo("ytLive.Tests")`.
+
+The layout DB is a **full rewrite per save** (delete all, re-insert from memory), so
+save/load round trips are exact: a source removed in the UI (`RemoveSource` →
+`scene.Sources.Remove` → `OnSourcesChanged` → debounced `ScheduleSave`, plus `Shutdown` on
+close) does **not** come back after reload (`LayoutStorePersistenceTests` guards this).
## Architecture
diff --git a/ytLive.Tests/LayoutStorePersistenceTests.cs b/ytLive.Tests/LayoutStorePersistenceTests.cs
new file mode 100644
index 0000000..36db8eb
--- /dev/null
+++ b/ytLive.Tests/LayoutStorePersistenceTests.cs
@@ -0,0 +1,50 @@
+using System;
+using System.IO;
+using Microsoft.Data.Sqlite;
+using Xunit;
+using ytLive.Models;
+using ytLive.Services;
+
+namespace ytLive.Tests;
+
+///
+/// The layout DB is a full rewrite on every save (DELETE all scenes/sources,
+/// re-insert from memory). This guards the round trip: sources the user deletes
+/// in the UI must not come back after a save + reload.
+///
+public class LayoutStorePersistenceTests
+{
+ [Fact]
+ public void Deleted_Webcam_Source_Does_Not_Return_After_Save_And_Reload()
+ {
+ var path = Path.Combine(Path.GetTempPath(), $"ytLlive-layout-{Guid.NewGuid():N}.db");
+ try
+ {
+ using var store = new LayoutStore(path);
+ var scene = new Scene { Name = "Starting" };
+ scene.Sources.Add(new Source
+ {
+ Name = "Webcam",
+ Type = SourceType.Webcam,
+ DeviceId = "real-device",
+ Width = 480,
+ Height = 270,
+ });
+ store.Save(new[] { scene });
+
+ var reloaded = store.Load();
+ Assert.Single(reloaded[0].Sources);
+
+ reloaded[0].Sources.RemoveAt(0);
+ store.Save(reloaded);
+
+ var afterDelete = store.Load();
+ Assert.Empty(afterDelete[0].Sources);
+ }
+ finally
+ {
+ SqliteConnection.ClearAllPools();
+ try { File.Delete(path); } catch { /* best-effort cleanup */ }
+ }
+ }
+}
diff --git a/ytLive.Tests/RoundClipInteractionTests.cs b/ytLive.Tests/RoundClipInteractionTests.cs
index c1379f8..24abbba 100644
--- a/ytLive.Tests/RoundClipInteractionTests.cs
+++ b/ytLive.Tests/RoundClipInteractionTests.cs
@@ -5,6 +5,7 @@ using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;
using System.Windows.Threading;
+using Microsoft.Data.Sqlite;
using Xunit;
using ytLive.Models;
using ytLive.ViewModels;
@@ -47,6 +48,11 @@ public sealed class RoundClipInteractionTests
var app = new App();
app.InitializeComponent();
+ // Never let the real MainWindow read/write the user's actual layout DB —
+ // Shutdown() saves the layout, which would persist these test sources
+ // over the real ones. Point it at a throwaway temp DB instead.
+ var tempDb = System.IO.Path.Combine(System.IO.Path.GetTempPath(), $"ytLlive-test-{Guid.NewGuid():N}.db");
+ MainViewModel.LayoutPathOverride = tempDb;
var window = new MainWindow();
var vm = (MainViewModel)window.DataContext;
try
@@ -103,6 +109,9 @@ public sealed class RoundClipInteractionTests
finally
{
window.Close();
+ MainViewModel.LayoutPathOverride = null;
+ SqliteConnection.ClearAllPools();
+ try { System.IO.File.Delete(tempDb); } catch { /* best-effort cleanup */ }
}
}
diff --git a/ytLive.csproj b/ytLive.csproj
index 6949ebd..1ed50ea 100644
--- a/ytLive.csproj
+++ b/ytLive.csproj
@@ -24,6 +24,12 @@
+
+
+ <_Parameter1>ytLive.Tests
+
+
+