test: add Android and iOS device tests run through dotnet test --device

.github/workflows/ci-build.yml

@@ -23,6 +23,9 @@ jobs:
       installWorkloads: true
       installWindowsAppRuntime: true
       # Test only the test projects: the solution also builds the documentation example apps, which are not tests.
-      testProjects: tests/**/*.csproj
+      # The device test app needs an emulator or simulator; device-tests.yml runs it.
+      testProjects: |
+        tests/**/*.csproj
+        !tests/ReactiveUI.Device.Tests/**
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/device-tests.yml

@@ -0,0 +1,19 @@
+name: Device Tests
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  device-tests:
+    uses: reactiveui/actions-common/.github/workflows/workflow-common-device-tests.yml@main
+    with:
+      projects: src/tests/ReactiveUI.Device.Tests/ReactiveUI.Device.Tests.csproj
+      configuration: Release
+      solutionFile: reactiveui.slnx

.github/workflows/sonarcloud.yml

@@ -17,7 +17,10 @@ jobs:
             installWorkloads: true
             installWindowsAppRuntime: true
             # Test only the test projects: the solution also builds the documentation example apps, which are not tests.
-            testProjects: tests/**/*.csproj
+            # The device test app needs an emulator or simulator; device-tests.yml runs it.
+            testProjects: |
+                tests/**/*.csproj
+                !tests/ReactiveUI.Device.Tests/**
             sonarProjectKey: reactiveui_ReactiveUI
             sonarOrganization: reactiveui
             sonarExclusions: '**/tests/**,**/integrationtests/**,**/benchmarks/**,**/examples/**,**/TestResults/**'

src/reactiveui.slnx

@@ -58,6 +58,7 @@
     <Folder Name="/Solution Items/Workflows/">
         <File Path="../.github/workflows/ci-build.yml" />
         <File Path="../.github/workflows/codeql.yml" />
+        <File Path="../.github/workflows/device-tests.yml" />
         <File Path="../.github/workflows/lock.yml" />
         <File Path="../.github/workflows/release.yml" />
         <File Path="../.github/workflows/sonarcloud.yml" />
@@ -68,6 +69,7 @@
         <Project Path="tests/ReactiveUI.Blazor.Tests.Reactive/ReactiveUI.Blazor.Tests.Reactive.csproj" />
         <Project Path="tests/ReactiveUI.Builder.Maui.Tests/ReactiveUI.Builder.Maui.Tests.csproj" />
         <Project Path="tests/ReactiveUI.Builder.Tests/ReactiveUI.Builder.Tests.csproj" />
+        <Project Path="tests/ReactiveUI.Device.Tests/ReactiveUI.Device.Tests.csproj" />
         <Project Path="tests/ReactiveUI.Maui.Tests/ReactiveUI.Maui.Tests.csproj" />
         <Project Path="tests/ReactiveUI.Splat.Tests/ReactiveUI.Splat.Tests.csproj" />
         <Project Path="tests/ReactiveUI.Test.Utilities/ReactiveUI.Test.Utilities.csproj" />

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Activities/ActivatingActivity.cs

@@ -0,0 +1,66 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.Widget;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>A <see cref="ReactiveActivity{TViewModel}"/> that counts its activations and wires its layout by name.</summary>
+[Activity(Exported = false)]
+public class ActivatingActivity : ReactiveActivity<TestViewModel>
+{
+    /// <summary>The number of times the activity has been activated.</summary>
+    private int _activations;
+
+    /// <summary>The number of times the activity has been deactivated.</summary>
+    private int _deactivations;
+
+    /// <summary>Initializes a new instance of the <see cref="ActivatingActivity"/> class.</summary>
+    public ActivatingActivity() =>
+        this.WhenActivated(disposables =>
+        {
+            _ = Interlocked.Increment(ref _activations);
+            disposables(new ActionDisposable(() => Interlocked.Increment(ref _deactivations)));
+        });
+
+    /// <summary>Gets the most recently created instance, so a test can reach the instance Android creates when it recreates one.</summary>
+    public static ActivatingActivity? LastCreated { get; private set; }
+
+    /// <summary>Gets the number of times the activity has been activated.</summary>
+    public int Activations => Volatile.Read(ref _activations);
+
+    /// <summary>Gets a value indicating whether Android passed saved state to <see cref="OnCreate(Bundle?)"/>.</summary>
+    public bool CreatedFromSavedState { get; private set; }
+
+    /// <summary>Gets the number of times the activity has been deactivated.</summary>
+    public int Deactivations => Volatile.Read(ref _deactivations);
+
+    /// <summary>Gets or sets the title control, wired by name.</summary>
+    public TextView? TitleText { get; set; }
+
+    /// <summary>Gets or sets the save button, wired by name.</summary>
+    public Button? SaveButton { get; set; }
+
+    /// <summary>Gets the error wiring the controls threw, if it threw.</summary>
+    public Exception? WireUpError { get; private set; }
+
+    /// <inheritdoc/>
+    protected override void OnCreate(Bundle? savedInstanceState)
+    {
+        base.OnCreate(savedInstanceState);
+        CreatedFromSavedState = savedInstanceState is not null;
+        LastCreated = this;
+        SetContentView(Resource.Layout.wireup_layout);
+
+        try
+        {
+            this.WireUpControls();
+        }
+        catch (MissingFieldException ex)
+        {
+            WireUpError = ex;
+        }
+    }
+}

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Activities/CompatHostActivity.cs

@@ -0,0 +1,38 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.Views;
+using Android.Widget;
+using ReactiveUI.AndroidX;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>A <see cref="ReactiveAppCompatActivity{TViewModel}"/> that hosts a <see cref="WiredFragment"/>.</summary>
+[Activity(Exported = false)]
+public class CompatHostActivity : ReactiveAppCompatActivity<TestViewModel>
+{
+    /// <summary>The number of times the activity has been activated.</summary>
+    private int _activations;
+
+    /// <summary>Initializes a new instance of the <see cref="CompatHostActivity"/> class.</summary>
+    public CompatHostActivity() =>
+        this.WhenActivated((Action<IDisposable> _) => Interlocked.Increment(ref _activations));
+
+    /// <summary>Gets the number of times the activity has been activated.</summary>
+    public int Activations => Volatile.Read(ref _activations);
+
+    /// <summary>Gets the hosted fragment.</summary>
+    public WiredFragment Fragment { get; } = new();
+
+    /// <inheritdoc/>
+    protected override void OnCreate(Bundle? savedInstanceState)
+    {
+        base.OnCreate(savedInstanceState);
+
+        var container = new FrameLayout(this) { Id = View.GenerateViewId() };
+        SetContentView(container);
+        SupportFragmentManager!.BeginTransaction()!.Add(container.Id, Fragment)!.CommitNow();
+    }
+}

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Activities/EchoBinder.cs

@@ -0,0 +1,17 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.OS;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>The binder <see cref="EchoService"/> returns; a local client receives this same instance.</summary>
+public class EchoBinder : Binder
+{
+    /// <summary>Returns the text it was given, so a test can call through the bound service.</summary>
+    /// <param name="text">The text to echo.</param>
+    /// <returns>The same text.</returns>
+    public string Echo(string text) => text;
+}

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Activities/EchoService.cs

@@ -0,0 +1,20 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.Content;
+using Android.OS;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>A local bound service the service-binding tests connect to.</summary>
+[Service(Exported = false)]
+public class EchoService : Service
+{
+    /// <summary>The binder handed to every client.</summary>
+    private readonly EchoBinder _binder = new();
+
+    /// <inheritdoc/>
+    public override IBinder? OnBind(Intent? intent) => _binder;
+}

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Activities/HostActivity.cs

@@ -0,0 +1,24 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.Widget;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>A plain activity whose content view the tests add views to, so the views attach to a real window.</summary>
+[Activity(Exported = false)]
+public class HostActivity : Activity
+{
+    /// <summary>Gets the container the tests add views to.</summary>
+    public FrameLayout Container { get; private set; } = null!;
+
+    /// <inheritdoc/>
+    protected override void OnCreate(Bundle? savedInstanceState)
+    {
+        base.OnCreate(savedInstanceState);
+        Container = new(this);
+        SetContentView(Container);
+    }
+}

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Activities/ResultSourceActivity.cs

@@ -0,0 +1,31 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.Content;
+using AndroidResult = Android.App.Result;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>An activity that returns a result to its caller as soon as it is created.</summary>
+[Activity(Exported = false)]
+public class ResultSourceActivity : Activity
+{
+    /// <summary>The intent extra key carrying the answer.</summary>
+    internal const string AnswerKey = "answer";
+
+    /// <summary>The answer the activity returns.</summary>
+    internal const int Answer = 42;
+
+    /// <inheritdoc/>
+    protected override void OnCreate(Bundle? savedInstanceState)
+    {
+        base.OnCreate(savedInstanceState);
+
+        var data = new Intent();
+        _ = data.PutExtra(AnswerKey, Answer);
+        SetResult(AndroidResult.Ok, data);
+        Finish();
+    }
+}

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Activities/WiredFragment.cs

@@ -0,0 +1,53 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.Views;
+using Android.Widget;
+using ReactiveUI.AndroidX;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>An AndroidX <see cref="ReactiveFragment{TViewModel}"/> that wires its layout by name and counts activations.</summary>
+public class WiredFragment : ReactiveUI.AndroidX.ReactiveFragment<TestViewModel>
+{
+    /// <summary>The number of times the fragment has been activated.</summary>
+    private int _activations;
+
+    /// <summary>The number of times the fragment has been deactivated.</summary>
+    private int _deactivations;
+
+    /// <summary>Initializes a new instance of the <see cref="WiredFragment"/> class.</summary>
+    public WiredFragment() =>
+        this.WhenActivated(disposables =>
+        {
+            _ = Interlocked.Increment(ref _activations);
+            disposables(new ActionDisposable(() => Interlocked.Increment(ref _deactivations)));
+        });
+
+    /// <summary>Gets the number of times the fragment has been activated.</summary>
+    public int Activations => Volatile.Read(ref _activations);
+
+    /// <summary>Gets the number of times the fragment has been deactivated.</summary>
+    public int Deactivations => Volatile.Read(ref _deactivations);
+
+    /// <summary>Gets or sets the title control, wired by name.</summary>
+    public TextView? TitleText { get; set; }
+
+    /// <summary>Gets or sets the renamed input, wired through its resource-name override.</summary>
+    [WireUpResource("renamed_input")]
+    public EditText? Input { get; set; }
+
+    /// <inheritdoc/>
+    public override View? OnCreateView(LayoutInflater? inflater, ViewGroup? container, Bundle? savedInstanceState)
+    {
+        if (inflater?.Inflate(Resource.Layout.wireup_layout, container, false) is not { } view)
+        {
+            return null;
+        }
+
+        this.WireUpControls(view);
+        return view;
+    }
+}

src/tests/ReactiveUI.Device.Tests/Platforms/Android/AndroidManifest.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+  <application android:label="ReactiveUI Device Tests" android:theme="@style/Theme.AppCompat.Light.NoActionBar" />
+</manifest>

src/tests/ReactiveUI.Device.Tests/Platforms/Android/Infrastructure/ActivityLauncher.cs

@@ -0,0 +1,40 @@
+// Copyright (c) 2009-2026 .NET Foundation and Contributors. All rights reserved.
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for full license information.
+
+using Android.Content;
+
+namespace ReactiveUI.Device.Tests;
+
+/// <summary>Starts and finishes real activities through the test instrumentation.</summary>
+internal static class ActivityLauncher
+{
+    /// <summary>Gets the application context of the app under test.</summary>
+    internal static Context TargetContext => TestInstrumentation.Current.TargetContext!;
+
+    /// <summary>Starts <typeparamref name="TActivity"/> and waits until it is resumed.</summary>
+    /// <typeparam name="TActivity">The activity type, declared in the manifest by its <c>[Activity]</c> attribute.</typeparam>
+    /// <returns>The resumed activity.</returns>
+    internal static Task<TActivity> StartAsync<TActivity>()
+        where TActivity : Activity =>
+        Task.Run(static () =>
+        {
+            var intent = new Intent(TargetContext, typeof(TActivity));
+            _ = intent.AddFlags(ActivityFlags.NewTask);
+
+            // StartActivitySync blocks until the activity is resumed and must not run on the main thread.
+            return (TActivity)TestInstrumentation.Current.StartActivitySync(intent)!;
+        });
+
+    /// <summary>Finishes <paramref name="activity"/> and waits for the main thread to go idle.</summary>
+    /// <param name="activity">The activity to finish.</param>
+    /// <returns>A task that completes once the finish has been processed.</returns>
+    internal static async Task FinishAsync(Activity activity)
+    {
+        ArgumentNullException.ThrowIfNull(activity);
+
+        await MainThread.RunAsync(activity.Finish).ConfigureAwait(false);
+        await Task.Run(TestInstrumentation.Current.WaitForIdleSync).ConfigureAwait(false);
+    }
+}