dotnet · idg10 · May 1, 2024 · Apr 30, 2024
diff --git a/Ix.NET/Integration/Android/Resources/Resource.Designer.cs b/Ix.NET/Integration/Android/Resources/Resource.Designer.cs
diff --git a/Rx.NET/Integration/Installation/Android/Resources/Resource.Designer.cs b/Rx.NET/Integration/Installation/Android/Resources/Resource.Designer.cs
diff --git a/Rx.NET/Source/src/Microsoft.Reactive.Testing/Microsoft.Reactive.Testing.csproj b/Rx.NET/Source/src/Microsoft.Reactive.Testing/Microsoft.Reactive.Testing.csproj
@@ -9,7 +9,7 @@
     <Description>Reactive Extensions (Rx) for .NET - Testing Library</Description>
     <PackageReadmeFile>readme.md</PackageReadmeFile>
     <!-- NB: A lot of CA and IDE warnings are disabled because of the .cs files included from xunit.assert.source. -->
-    <NoWarn>$(NoWarn);IDE0054;IDE0066;CA1305;CA1307;CA1032;CA1064;CA1704;CA1822;CA1812;CA1820;CA1823;CA1825;CA1845;CA2249;IDE0016;IDE0018;IDE0019;IDE0020;IDE0031;IDE0039;IDE0044;IDE0059;IDE0074;IDE0270</NoWarn>
+    <NoWarn>$(NoWarn);IDE0054;IDE0066;CA1305;CA1307;CA1032;CA1064;CA1704;CA1822;CA1812;CA1820;CA1823;CA1825;CA1845;CA2249;IDE0016;IDE0018;IDE0019;IDE0020;IDE0028;IDE0031;IDE0039;IDE0044;IDE0059;IDE0074;IDE0090;IDE0270;IDE0300</NoWarn>
   </PropertyGroup>
 
   <PropertyGroup>

diff --git a/Rx.NET/Source/src/System.Reactive/Internal/Lookup.cs b/Rx.NET/Source/src/System.Reactive/Internal/Lookup.cs
@@ -39,7 +39,7 @@ public IEnumerable<E> this[K key]
             {
                 if (!_dictionary.TryGetValue(key, out var list))
                 {
-                    return Enumerable.Empty<E>();
+                    return [];
                 }
 
                 return Hide(list);

diff --git a/Rx.NET/Source/src/System.Reactive/Linq/Observable/Buffer.cs b/Rx.NET/Source/src/System.Reactive/Linq/Observable/Buffer.cs
@@ -29,7 +29,7 @@ internal sealed class ExactSink : Sink<TSource, IList<TSource>>
             {
                 private readonly int _count;
                 private int _index;
-                private IList<TSource>? _buffer;
+                private List<TSource>? _buffer;
 
                 internal ExactSink(IObserver<IList<TSource>> observer, int count) : base(observer)
                 {
@@ -41,7 +41,7 @@ public override void OnNext(TSource value)
                     var buffer = _buffer;
                     if (buffer == null)
                     {
-                        buffer = new List<TSource>();
+                        buffer = [];
                         _buffer = buffer;
                     }
 
@@ -102,7 +102,7 @@ internal sealed class SkipSink : Sink<TSource, IList<TSource>>
                 private readonly int _count;
                 private readonly int _skip;
                 private int _index;
-                private IList<TSource>? _buffer;
+                private List<TSource>? _buffer;
 
                 internal SkipSink(IObserver<IList<TSource>> observer, int count, int skip) : base(observer)
                 {
@@ -116,7 +116,7 @@ public override void OnNext(TSource value)
                     var buffer = _buffer;
                     if (idx == 0)
                     {
-                        buffer = new List<TSource>();
+                        buffer = [];
                         _buffer = buffer;
                     }
 

diff --git a/Rx.NET/Source/src/System.Reactive/Linq/Observable/FromEventPattern.cs b/Rx.NET/Source/src/System.Reactive/Linq/Observable/FromEventPattern.cs
@@ -135,13 +135,13 @@ public void Dispose()
 
             private Action AddHandlerCore(Delegate handler)
             {
-                _addMethod.Invoke(_target, new object[] { handler });
-                return () => _removeMethod.Invoke(_target, new object[] { handler });
+                _addMethod.Invoke(_target, [handler]);
+                return () => _removeMethod.Invoke(_target, [handler]);
             }
 
             private Action AddHandlerCoreWinRT(Delegate handler)
             {
-                var token = _addMethod.Invoke(_target, new object[] { handler });
+                var token = _addMethod.Invoke(_target, [handler]);
                 return () => _removeMethod.Invoke(_target, [token]);
             }
         }

diff --git a/Rx.NET/Source/src/System.Reactive/Linq/QueryLanguage.Blocking.cs b/Rx.NET/Source/src/System.Reactive/Linq/QueryLanguage.Blocking.cs
@@ -16,7 +16,7 @@ internal partial class QueryLanguage
 
         public virtual IEnumerable<IList<TSource>> Chunkify<TSource>(IObservable<TSource> source)
         {
-            return source.Collect<TSource, IList<TSource>>(() => new List<TSource>(), (lst, x) => { lst.Add(x); return lst; }, _ => new List<TSource>());
+            return source.Collect<TSource, IList<TSource>>(() => [], (lst, x) => { lst.Add(x); return lst; }, _ => []);
         }
 
         #endregion

diff --git a/Rx.NET/Source/src/System.Reactive/ObservableQuery.cs b/Rx.NET/Source/src/System.Reactive/ObservableQuery.cs
@@ -322,13 +322,13 @@ private IList<Expression> VisitQbservableOperatorArguments(MethodInfo method, IE
                     if (lastArgument.NodeType == ExpressionType.NewArrayInit)
                     {
                         var paramsArray = (NewArrayExpression)lastArgument;
-                        return new List<Expression>
-                        {
+                        return
+                        [
                             Expression.NewArrayInit(
                                 typeof(Plan<>).MakeGenericType(method.GetGenericArguments()[0]),
                                 paramsArray.Expressions.Select(param => Visit(param))
                             )
-                        };
+                        ];
                     }
                 }
 

diff --git a/Rx.NET/Source/src/System.Reactive/Subjects/AsyncSubject.cs b/Rx.NET/Source/src/System.Reactive/Subjects/AsyncSubject.cs
@@ -22,7 +22,7 @@ public sealed class AsyncSubject<T> : SubjectBase<T>, INotifyCompletion
         private bool _hasValue;
         private Exception? _exception;
 
-#pragma warning disable CA1825 // (Avoid zero-length array allocations.) The identity of these arrays matters, so we can't use the shared Array.Empty<T>() instance
+#pragma warning disable CA1825,IDE0300 // (Avoid zero-length array allocations. Use collection expressions) The identity of these arrays matters, so we can't use the shared Array.Empty<T>() instance either explicitly, or indirectly via a collection expression
         /// <summary>
         /// A pre-allocated empty array indicating the AsyncSubject has terminated.
         /// </summary>
@@ -31,7 +31,7 @@ public sealed class AsyncSubject<T> : SubjectBase<T>, INotifyCompletion
         /// A pre-allocated empty array indicating the AsyncSubject has been disposed.
         /// </summary>
         private static readonly AsyncSubjectDisposable[] Disposed = new AsyncSubjectDisposable[0];
-#pragma warning restore CA1825
+#pragma warning restore CA1825,IDE0300
 
         #endregion
 

diff --git a/Rx.NET/Source/src/System.Reactive/Subjects/Subject.cs b/Rx.NET/Source/src/System.Reactive/Subjects/Subject.cs
@@ -18,10 +18,10 @@ public sealed class Subject<T> : SubjectBase<T>
 
         private SubjectDisposable[] _observers;
         private Exception? _exception;
-#pragma warning disable CA1825 // (Avoid zero-length array allocations.) The identity of these arrays matters, so we can't use the shared Array.Empty<T>() instance
+#pragma warning disable CA1825,IDE0300 // (Avoid zero-length array allocations. Use collection expressions) The identity of these arrays matters, so we can't use the shared Array.Empty<T>() instance either explicitly, or indirectly via a collection expression
         private static readonly SubjectDisposable[] Terminated = new SubjectDisposable[0];
         private static readonly SubjectDisposable[] Disposed = new SubjectDisposable[0];
-#pragma warning restore CA1825
+#pragma warning restore CA1825,IDE0300
 
         #endregion
 

diff --git a/Rx.NET/Source/tests/Tests.System.Reactive.ApiApprovals/Api/ApiApprovalTests.cs b/Rx.NET/Source/tests/Tests.System.Reactive.ApiApprovals/Api/ApiApprovalTests.cs
@@ -50,7 +50,7 @@ private string GeneratePublicApi(Assembly assembly)
         {
             ApiGeneratorOptions options = new()
             {
-                AllowNamespacePrefixes = new[] { "System", "Microsoft" }
+                AllowNamespacePrefixes = ["System", "Microsoft"]
             };
             return Filter(ApiGenerator.GeneratePublicApi(assembly, options));
         }

diff --git a/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Aliases.cs b/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Aliases.cs
@@ -21,10 +21,10 @@ public void Qbservable_Aliases()
         {
             var xs = Observable.Return(1).AsQbservable();
 
-            Assert.True(xs.Filter(x => true).ToEnumerable().SequenceEqual(new[] { 1 }), "Filter");
-            Assert.True(xs.Filter(x => true).Concat(xs.Filter(x => false)).ToEnumerable().SequenceEqual(new[] { 1 }), "Concat/Filter");
-            Assert.True(xs.Map(x => x.ToString()).ToEnumerable().SequenceEqual(new[] { "1" }), "Map");
-            Assert.True(xs.FlatMap(x => xs).ToEnumerable().SequenceEqual(new[] { 1 }), "FlatMap");
+            Assert.True(xs.Filter(x => true).ToEnumerable().SequenceEqual([1]), "Filter");
+            Assert.True(xs.Filter(x => true).Concat(xs.Filter(x => false)).ToEnumerable().SequenceEqual([1]), "Concat/Filter");
+            Assert.True(xs.Map(x => x.ToString()).ToEnumerable().SequenceEqual(["1"]), "Map");
+            Assert.True(xs.FlatMap(x => xs).ToEnumerable().SequenceEqual([1]), "FlatMap");
         }
     }
 }
diff --git a/Rx.NET/Source/tests/Tests.System.Reactive/Tests/ArgumentValidationTest.cs b/Rx.NET/Source/tests/Tests.System.Reactive/Tests/ArgumentValidationTest.cs
@@ -40,6 +40,7 @@ public class ArgumentValidationTest
         /// </summary>
         static ArgumentValidationTest()
         {
+#pragma warning disable IDE0300 // Simplify collection initialization. We want to be clear about what kinds of collections are in use in these tests.
             _defaultValues = new Dictionary<string, object>
             {
                 { "IObservable`1[Object]", Observable.Return(new object()) },
@@ -269,6 +270,7 @@ static ArgumentValidationTest()
 
                 { "Func`17[Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32, AsyncCallback, Object, IAsyncResult]", new Func<int, int, int, int, int, int, int, int, int, int, int, int, int, int, AsyncCallback, object, IAsyncResult>((v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16) => null) }
             };
+#pragma warning restore IDE0300 // Simplify collection initialization
         }
 
         #endregion

diff --git a/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Concurrency/SchedulerTest.cs b/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Concurrency/SchedulerTest.cs
@@ -479,7 +479,7 @@ public void OnResuming()
         public void DisableOptimizations_ArgumentChecking()
         {
             ReactiveAssert.Throws<ArgumentNullException>(() => Scheduler.DisableOptimizations(default));
-            ReactiveAssert.Throws<ArgumentNullException>(() => Scheduler.DisableOptimizations(default, new Type[0]));
+            ReactiveAssert.Throws<ArgumentNullException>(() => Scheduler.DisableOptimizations(default, []));
 #if !WINDOWS
             ReactiveAssert.Throws<ArgumentNullException>(() => Scheduler.DisableOptimizations(ThreadPoolScheduler.Instance, default));
 #endif

diff --git a/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Disposables/DisposableTests.cs b/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Disposables/DisposableTests.cs
@@ -196,7 +196,7 @@ public void CompositeDisposable_ToArray()
             var g = new CompositeDisposable(d1, d2);
             Assert.Equal(2, g.Count);
             var x = Enumerable.ToArray(g);
-            Assert.True(g.ToArray().SequenceEqual(new[] { d1, d2 }));
+            Assert.True(g.ToArray().SequenceEqual([d1, d2]));
         }
 
         [TestMethod]
@@ -211,7 +211,7 @@ public void CompositeDisposable_GetEnumerator()
                 lst.Add(x);
             }
 
-            Assert.True(lst.SequenceEqual(new[] { d1, d2 }));
+            Assert.True(lst.SequenceEqual([d1, d2]));
         }
 
         [TestMethod]
@@ -226,7 +226,7 @@ public void CompositeDisposable_GetEnumeratorNonGeneric()
                 lst.Add(x);
             }
 
-            Assert.True(lst.SequenceEqual(new[] { d1, d2 }));
+            Assert.True(lst.SequenceEqual([d1, d2]));
         }
 
         [TestMethod]
@@ -252,7 +252,7 @@ public void CompositeDisposable_AddNull_via_params_ctor()
         [TestMethod]
         public void CompositeDisposable_AddNull_via_IEnum_ctor()
         {
-            IEnumerable<IDisposable> values = new IDisposable[] { null };
+            IEnumerable<IDisposable> values = [null];
 #pragma warning disable CA1806 // (Unused new instance.) We expect the constructor to throw.
             ReactiveAssert.Throws<ArgumentException>(() => new CompositeDisposable(values));
 #pragma warning restore CA1806
@@ -882,7 +882,7 @@ public void StableCompositeDisposable_Nary2()
             var disp3 = false;
             var d3 = Disposable.Create(() => { Assert.False(disp3); disp3 = true; });
 
-            var d = StableCompositeDisposable.Create(new List<IDisposable>(new[] { d1, d2, d3 }));
+            var d = StableCompositeDisposable.Create(new List<IDisposable>([d1, d2, d3]));
 
             Assert.False(disp1);
             Assert.False(disp2);

diff --git a/Rx.NET/Source/tests/Tests.System.Reactive/Tests/ImmutableListTest.cs b/Rx.NET/Source/tests/Tests.System.Reactive/Tests/ImmutableListTest.cs
@@ -21,53 +21,53 @@ public void ImmutableList_Basics()
         {
             var list = ImmutableList<int>.Empty;
 
-            Assert.True(list.Data.SequenceEqual(new int[] { }));
+            Assert.True(list.Data.SequenceEqual([]));
 
             list = list.Add(42);
 
-            Assert.True(list.Data.SequenceEqual(new int[] { 42 }));
+            Assert.True(list.Data.SequenceEqual([42]));
 
             list = list.Remove(42);
 
-            Assert.True(list.Data.SequenceEqual(new int[] { }));
+            Assert.True(list.Data.SequenceEqual([]));
 
             list = list.Remove(42);
 
-            Assert.True(list.Data.SequenceEqual(new int[] { }));
+            Assert.True(list.Data.SequenceEqual([]));
 
             list = list.Add(43);
             list = list.Add(44);
             list = list.Add(43);
 
-            Assert.True(list.Data.SequenceEqual(new int[] { 43, 44, 43 }));
+            Assert.True(list.Data.SequenceEqual([43, 44, 43]));
 
             list = list.Remove(43);
 
-            Assert.True(list.Data.SequenceEqual(new int[] { 44, 43 }));
+            Assert.True(list.Data.SequenceEqual([44, 43]));
 
             list = list.Remove(43);
 
-            Assert.True(list.Data.SequenceEqual(new int[] { 44 }));
+            Assert.True(list.Data.SequenceEqual([44]));
 
             list = list.Remove(44);
 
-            Assert.True(list.Data.SequenceEqual(new int[] { }));
+            Assert.True(list.Data.SequenceEqual([]));
         }
 
         [TestMethod]
         public void ImmutableList_Nulls()
         {
             var list = ImmutableList<string>.Empty;
 
-            Assert.True(list.Data.SequenceEqual(new string[] { }));
+            Assert.True(list.Data.SequenceEqual([]));
 
             list = list.Add(null);
 
-            Assert.True(list.Data.SequenceEqual(new string[] { null }));
+            Assert.True(list.Data.SequenceEqual([null]));
 
             list = list.Remove(null);
 
-            Assert.True(list.Data.SequenceEqual(new string[] { }));
+            Assert.True(list.Data.SequenceEqual([]));
         }
     }
 #endif

diff --git a/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Linq/Observable/AutoConnectTest.cs b/Rx.NET/Source/tests/Tests.System.Reactive/Tests/Linq/Observable/AutoConnectTest.cs
@@ -12,6 +12,8 @@
 
 using Assert = Xunit.Assert;
 
+#pragma warning disable IDE0028 // Simplify collection initialization. Using this in Assert.Equals makes it unclear what types are actually in use.
+
 namespace ReactiveTests.Tests
 {
     [TestClass]