add tests for reading value in OnChange callback

dombrovsky · Oct 23, 2022 · 026ad02 · 026ad02
1 parent 800c6fd
commit 026ad02
Show file tree

Hide file tree

Showing 4 changed files with 100 additions and 1 deletion.
diff --git a/MutableOptions.Tests/MutableOptionsMonitorTests.cs b/MutableOptions.Tests/MutableOptionsMonitorTests.cs
@@ -1,8 +1,11 @@
 namespace MutableOptions.Tests
 {
+    using Microsoft.Extensions.Configuration;
     using Microsoft.Extensions.DependencyInjection;
+    using Microsoft.Extensions.Hosting;
     using Microsoft.Extensions.Options;
     using Microsoft.Extensions.Options.Mutable;
+    using MutableOptions.Tests.TestOptions;
     using NUnit.Framework;
 
     [TestFixture]
@@ -17,5 +20,37 @@ protected override IOptionsMonitor<T> CreateOptionsMonitor<T>(IServiceProvider s
         {
             return serviceProvider.GetRequiredService<IMutableOptionsMonitor<T>>();
         }
+
+        [Test]
+        public void NotifyPropertyChangedWrapper_ReadingCurrentValueFromChangedCallback_ShouldReturnNewValue()
+        {
+            var configData = new[]
+            {
+                new KeyValuePair<string, string>("StringValue", "foo"),
+            };
+
+            using var host = Host.CreateDefaultBuilder(Array.Empty<string>())
+                .ConfigureAppConfiguration(builder => builder.AddInMemoryCollection(configData))
+                .ConfigureServices((context, services) =>
+                {
+                    services.ConfigureMutable<SimpleOptions>(context.Configuration);
+                    services.AddSingleton<SimpleSettingsService>();
+                })
+                .Build();
+
+            var simpleSettingsService = host.Services.GetRequiredService<SimpleSettingsService>();
+            Assert.That(simpleSettingsService.StringValue, Is.Not.EqualTo("bar"));
+
+            var onChangeCalledTimes = 0;
+            simpleSettingsService.PropertyChanged += (_, _) =>
+            {
+                Assert.That(simpleSettingsService.StringValue, Is.EqualTo("bar"));
+                onChangeCalledTimes++;
+            };
+
+            simpleSettingsService.StringValue = "bar";
+
+            Assert.That(onChangeCalledTimes, Is.EqualTo(1));
+        }
     }
 }
diff --git a/MutableOptions.Tests/OptionsMutatorTests.cs b/MutableOptions.Tests/OptionsMutatorTests.cs
@@ -23,6 +23,35 @@ public void Setup()
                 .Returns(info => EqualityComparer<SimpleOptions>.Default.Equals(info.ArgAt<SimpleOptions?>(0), info.ArgAt<SimpleOptions?>(1)));
         }
 
+        [Test]
+        public void OptionsMonitor_ReadingCurrentValueFromChangedCallback_ShouldReturnNewValue()
+        {
+            var configData = new[]
+            {
+                new KeyValuePair<string, string>("StringValue", "foo"),
+            };
+
+            using var host = Host.CreateDefaultBuilder(Array.Empty<string>())
+                .ConfigureAppConfiguration(builder => builder.AddInMemoryCollection(configData))
+                .ConfigureServices((context, services) => services.ConfigureMutable<SimpleOptions>(context.Configuration))
+                .Build();
+
+            var optionsMonitor = CreateOptionsMonitor<SimpleOptions>(host.Services);
+            Assert.That(optionsMonitor.CurrentValue.StringValue, Is.Not.EqualTo("bar"));
+
+            var onChangeCalledTimes = 0;
+            optionsMonitor.OnChange(options =>
+            {
+                Assert.That(optionsMonitor.CurrentValue.StringValue, Is.EqualTo("bar").And.EqualTo(options.StringValue));
+                onChangeCalledTimes++;
+            });
+
+            var optionsMutator = CreateSut<SimpleOptions>(host.Services);
+            optionsMutator.Mutate(options => options with { StringValue = "bar" });
+
+            Assert.That(onChangeCalledTimes, Is.EqualTo(1));
+        }
+
         [Test]
         public void ConfigurationEmpty_WhenMutate_ShouldWriteToConfiguration()
         {

diff --git a/MutableOptions.Tests/TestOptions/SimpleSettingsService.cs b/MutableOptions.Tests/TestOptions/SimpleSettingsService.cs
@@ -0,0 +1,35 @@
+namespace MutableOptions.Tests.TestOptions
+{
+    using Microsoft.Extensions.Options.Mutable;
+    using System.ComponentModel;
+
+    internal sealed class SimpleSettingsService : INotifyPropertyChanged, IDisposable
+    {
+        private readonly IMutableOptionsMonitor<SimpleOptions> _mutableOptionsMonitor;
+        private readonly IDisposable _changeSubscription;
+
+        public SimpleSettingsService(IMutableOptionsMonitor<SimpleOptions> mutableOptionsMonitor)
+        {
+            _mutableOptionsMonitor = mutableOptionsMonitor;
+            _changeSubscription = _mutableOptionsMonitor.OnChange(HandleSimpleOptionsChanged);
+        }
+
+        public event PropertyChangedEventHandler? PropertyChanged;
+
+        public string StringValue
+        {
+            get => _mutableOptionsMonitor.CurrentValue.StringValue;
+            set => _mutableOptionsMonitor.Mutate(options => options with { StringValue = value });
+        }
+
+        public void Dispose()
+        {
+            _changeSubscription.Dispose();
+        }
+
+        private void HandleSimpleOptionsChanged(SimpleOptions simpleOptions, string name)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(null));
+        }
+    }
+}
diff --git a/MutableOptions/MutableOptions.csproj b/MutableOptions/MutableOptions.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 	<PropertyGroup>
 		<LangVersion>10</LangVersion>
-		<TargetFrameworks>netstandard2.0;netstandard2.1;net6.0</TargetFrameworks>
+		<TargetFrameworks>netstandard2.0;net6.0</TargetFrameworks>
 		<Nullable>enable</Nullable>
 		<TreatWarningsAsErrors>True</TreatWarningsAsErrors>
 		<Deterministic>true</Deterministic>